http://www.ianr.unl.edu/pubs/forestry/ec1764.htm Windbreak Establishment, EC91-1764-B This publication discusses how to establish windbreaks successfully, including site preparation, weed control, and tree replanting." University of Nebraska Extension, EC91-1764-B By Patricia Boehner and James R.Brandle, University of Nebraska-Lincoln and Sherman Finch, Soil Conservation Service wind-1a.jpg photo: weed-free windbreak wind-1.jpg A successful windbreak planting depends on proper establishment and care during the first few years after planting. Time spent in site preparation, weed control, and replanting is repaid many times during the lifetime of the windbreak. Take no shortcuts in the planning and establishment of your windbreak. _Time and effort spent on proper weed control and protection during the early years of a planting help ensure a healthy and functional windbreak. _ Photo: G Alexander, SCS. Windbreaks are investments in the future value of your property. Each windbreak system is unique and your windbreak should be designed for your site and objectives. Your local conservation office can provide help in designing and installing your windbreak. These organizations can also help with recommendations on where to buy planting stock and how to treat your windbreak as investment. Windbreak Layout and Design Layout Before planting, it is best to layout each row of the windbreak on the actual site. This will allow the design to be customized for the positions of buildings, roads or driveways, feedlots, field boundaries, utility lines, drainage ditches, and other features at your site. Lay out the dimensions of the windbreak, including the spacing within and between tree rows. This process will help assure that your design will provide the protection needed and will fit within the desired area. Site preparation _For successful tree establishment in grasslands, killing the grass and breaking up the sod are essential preparation practices on most sites._ Photo: G. Alexander, SCS. Proper site preparation is one of the best ways to improve the survival of your newly planted trees and shrubs. Preliminary groundwork reduces competition from weedy species, conserves soil moisture, and makes planting easier. Site preparation actually begins the year before planting and depends on the condition of your site. Soil type, existing vegetation, and possible erosion hazards should be considered in selecting the appropriate practices. If rodents are a problem in the area, begin control measures at least a year in advance. You may obtain recommendations for site preparation techniques from local conservation agencies. Cropland Depending on the current weed density, little or no site preparation is necessary on previously cultivated land. If many weeds are present, the land may require a single disking before planting. Otherwise, plant directly into the previous year's crop stubble. Avoid exposing erodible soils to the wind. If erosion is a threat over the winter, plant a fall cover crop. The following spring, treat the existing vegetation with herbicide, and plant the windbreak directly into the cover crop residue. Grassland or Rangeland On sites with heavy grass sod, site preparation begins with a herbicide application in the spring while the grass is actively growing. The site is then plowed in the fall and disked the following spring just prior to planting. Delaying disking until just before planting conserves soil moisture, controls early spring weeds, and reduces the potential for erosion damage. In rangelands where erosion may be a major concern, chemical fallowing practices offer the best alternative to mechanical cultivation. To assure complete control, apply the chemicals in the spring, at least two weeks before tree planting and when the grass is actively growing. Planting directly into the dead sod reduces the chance of soil erosion but replanting costs may be higher since the matted sod, even when the grass is dead, may cause competition for the establishment of tree roots. Planting After you prepare your site, successful establishment depends on planting quality plant material, handling the plant material carefully, and using proper planting techniques. Plant Material Selection Purchase your stock from a reliable source. Most states sell trees through the State Forester's office at very reasonable prices. Private nurseries usually have comparable prices, and may have additional species. Choose plant material that is suitable for your soils and can survive the environmental extremes at your site. Consult your county extension office or another local conservation agency for lists of suitable trees and shrubs. Your seedlings should come from nurseries using locally collected seed or seed from known origins. When available, select insect and/or disease resistant plants. Don't be too quick to buy the cheapest seedlings; they may not be the best value in the long run. Conifers should be at least 8 to 12 inches tall, with a good, healthy root system. Trees may be either container-grown or bare-root. Container-grown plants are usually larger and cost more, but may be worth the extra cost in areas where establishment is difficult. Usually, quality bare-root stock is satisfactory. Most nurseries sell hardwoods and shrubs as bareroot seedlings. They should be 12 to 24 inches tall, with full, healthy root systems, and at least a one- quarter inch diameter just above the root collar (the point where the roots meet the stem). Pre-Planting Care A crucial step in the establishment process is the care of plant material upon arrival. Warm temperatures and dryness greatly reduce the survivability of seedlings. Immediately upon arrival, inspect the plant material for dry, moldy, or very small trees. Do not waste your time planting damaged trees. Plant your windbreak as soon as possible after the seedlings arrive. Ideally, seedlings should be planted the same day they are received. This is not always possible and your seedlings may need to be stored until planting conditions improve. How well you store your seedlings will determine the success of your tree planting. If seedlings need to be stored there are several methods that will minimize the stress of storage. Keep the packing material around the roots and making sure the roots are damp. Check them daily for adequate moisture and keep the box or bag closed so that the seedlings remain in the dark. Refrigerated storage (34-40 deg F; 80-100 percent humidity) is best and will allow seedlings to be kept for several weeks. _DO NOT_ allow the seedlings to freeze. A cool, damp root cellar will provide satisfactory storage for up to a week. Placing several trays of ice cubes on top of the packing material covering the roots will provide cooling and moisture. Repeat the process daily. _DO NOT_ use dry ice as this will freeze the plant material. A cool basement or unheated room will provide satisfactory storage for several days. Again, ice cubes placed on the packing material will provide both cool temperatures and moisture. The best time to plant tree seedlings is in the spring, before the buds begin to swell. Fall planting is usually not very successful. To minimize stress on the seedlings during planting, try to plant on a calm or cloudy day, and keep the trees moist. It is extremely important to avoid the exposure of seedlings, especially bareroot conifers, to air any longer than absolutely necessary. Keep seedlings in the original, moist packing material, or covered with wet burlap. If practical, placing the roots in a bucket containing a slurry of soil and water will provide a coating for the roots and keep them from drying out. Commercially prepared slurries are also available. Although dryness damages the roots, they do need some oxygen; therefore, _DO NOT_ store the seedlings with their roots in water or in the slurry for more than several hours. Planting Techniques There are essentially two ways to plant trees--by hand or by machine. Both provide excellent results, and the method of choice usually depends on the number of trees you are planting. If you have many trees to plant, contact your local extension office to find out if help is available. Many state or federal agencies offer planting services, or cooperate with locally owned tree planting services. Some offices will rent you a tree planter if you wish to do your own planting. If your windbreak is put in by machine, supply the equipment operators with copies of your site plan. After planting by machine, walk the entire windbreak strip. Lightly tug on the seedlings while tamping the soil at the base of each tree to be sure they are vertical and firmly in the ground. Good root-soil contact is essential to a successful planting. If the soil is dry, the seedlings will benefit from a small amount of water (approximately 1 gallon) applied at planting. wind-3.gif" _Figure 1. Drawings 1 through 11 illustrate various ways that trees should NOT be planted. The ideal planting is shown in drawing 12._ Post-planting care Windbreak establishment does not end once the seedlings are in the ground. The new planting is still susceptible to weed competition, hot dry winds, feeding by livestock and rodents, and damage from insects and diseases. Weed Control Competition from weeds is the leading cause for failure of newly planted windbreaks. Pre-emergent herbicides can reduce the weed populations and minimize cultivation. On areas subject to erosion, vegetation can be controlled with various herbicides. Consult your local conservation agency for the best herbicides for your planting. When using herbicides always read and follow label instructions. wind-4.jpg _Various types of mulches may also be used to control weeds and conserve moisture. Plastic mulches and other mat-type weed barriers are cost effective and are especially useful at remote sites._ Photo: G. Alexander, SCS. Consistent vegetation control insures a vigorous, well-established windbreak. Clean cultivation of newly planted windbreaks gives the trees an advantage in obtaining moisture. However, some vegetation between rows reduces soil erosion and drying caused by strong winds. Planting an annual crop such as corn or sorghum between the rows protects the soil and young trees (especially conifers) from wind damage and will trap snow in the winter for added moisture. At a minimum, an area thirty-six inches in diameter around each tree should be free of grass and weeds for 3 to 5 years. Livestock Keep livestock out of windbreaks at all times. Livestock browse and trample young seedlings, cause soil compaction, and reduce the effectiveness of the lower portions of the windbreak. Use fences to protect your windbreak anytime livestock are nearby. Wildlife Damage Newly planted trees and shrubs are particularly susceptible to damage by small mammals. If rodents are a problem, continue control measures initiated the previous year. An advantage of clean cultivation after establishment is that small rodents tend to avoid bare ground. If the planting is relatively small, fencing with chicken-wire or plastic guards provides a barrier to rabbits and most other small mammals. Commercial animal repellents are also available, but are not always reliable. Insects and Diseases Inspect your windbreaks regularly for signs of insects or diseases. Early identification allows early control of these situations--before damage decreases windbreak effectiveness. Stressed trees can conceal the effects of insects and diseases, so be particularly alert for outbreaks during dry years. Irrigation In low rainfall regions or under drought conditions, supplemental water may be necessary for the survival of newly planted trees and shrubs. Various types of drip irrigation systems are available, and in some regions may receive cost-share funding. In very dry areas, it is essential for newly planted trees to receive additional watering at the time of planting. Replanting Even under the best of conditions, some seedlings die. Check for and replace dead seedlings for at least three years. The effectiveness of a windbreak depends largely on the initial impact of the wind against full, compact rows of trees and shrubs. Gaps or low density areas within the windbreak concentrate the force of the wind, causing more problems than in unprotected areas. EC1764 mailto:pubs@unl.edu?subject=Comments from EC1764 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. This series of windbreak publications is jointly sponsored by the University of Nebraska, USDA Natural Resources Conservation Service, USDA Forest Service, North Dakota State University, and the Forest Stewardship Program of The Nebraska Forest Service. Its goal is to encourage the proper management of all our woodland resources. http://www.ianr.unl.edu/pubs/forestry/ec1766.htm Windbreaks for Livestock Operations, EC 94-1766 This publication discusses how well-designed windbreaks benefit feedlots, livestock pastures, and calving areas." University of Nebraska Cooperative Extension EC 94-1766-X Windbreaks for Livestock Operations By Vernon Quam and LaDon Johnson, North Dakota State University Bruce Wight, Soil Conservation Service James R Brandle, University of Nebraska breakcw2.jpg photo: cow and windbreak breakcow.jpg Windbreaks play an important role in the protection of livestock, particularly in young animals and in areas with cold northerly winds during the winter and early spring. Properly placed windbreaks can provide benefits to feedlots, livestock pastures, and calving areas. Reducing wind speed in winter lowers animal stress, improves animal health, and increases feeding efficiency. Livestock windbreaks provide significant amounts of wildlife habitat, protect the working environment in and around the livestock area, and screen noise and odors associated with livestock operations. Specific needs of animals dictate that special attention be given to access, snow storage, and drainage when planning a livestock windbreak. Each windbreak should be designed to meet the specific livestock operation. A well- thought-out and properly cared for windbreak protects livestock in both the winter and summer and will provide economic benefits to the landowner over the long term. The time spent on layout, site preparation, weed control, and replanting is paid back many times throughout the life of a windbreak. _Protecting your livestock from cold winds can reduce your feed requirements and improve your profitability._ Photo: USDA Benefits of Livestock Windbreaks Winter Protection All warm-blooded animals must maintain their body temperatures within a relative narrow range or comfort zone. When air temperature falls below this range the animal must expend energy to keep warm. As winter approaches, many animals develop winter coats as insulation against the cold. In the case of beef cattle, a heavy winter coat will provide protection against temperatures as low as 18 degrees (Table 1). At temperatures below 18 degrees the animal is stressed and begins to require additional feed in order to maintain body temperature. Exposure to winter winds will increase the need for additional feed. If the temperature reaches zero degrees and wind speed is 25 mph, the windchill is 44 degrees below zero (Table 2). Under these extreme stress conditions, animals require significantly more feed, are less efficient at converting this feed into energy, and are more susceptible to latent diseases or other health problems. In contrast, when windbreaks are present, the reduced wind speed in the protected zone reduces the windchill temperature to 15 degrees below zero. While some danger remains for young or newborn animals, danger to mature animals is greatly reduced. _Table 1. Critical temperatures for beef cattle are determined in part by the condition of the coat. Below the critical temperature, livestock must expend more energy in order to keep warm._ _Coat Description_ _Critical Temperature_ Summer coat or wet 59 deg F Fall coat 45 deg F Winter coat 32 deg F Heavy winter coat 18 deg F Adapted from D.R. Ames, Kansas State University. Kansas cattle producers indicate, that on average, calving success increases by 2 percent if cows are protected by a windbreak. Canadian researchers found that cattle on winter range, in unprotected sites, required a 50 percent increase in feed for normal activities. An additional 20 percent increase was necessary to overcome the direct effects of exposure to a combination of cold temperatures and wind. Wind protection reduced these needs by half. The amount of feed required to maintain body temperature in cattle is reduced when they are protected by windbreaks. For example, an 880-pound animal, with its winter coat, has a critical temperature of 32 degrees (Table 1) and requires 1.1 percent more feed per degree of cold (Table 3). If the temperature is 10 degrees and the wind speed is 10 miles per hour, the windchill temperature is 9 degrees below zero (Table 2) and the animal needs 45 percent more feed (critical temperature minus windchill temperature times increased feed requirement). If this same animal were protected by a windbreak providing a 70 percent reduction in wind speed, the windchill factor would change from minus 9 degrees to 2 degrees above zero. The degrees of cold would be 30 and the increase feed requirement would be only 33 percent, a savings of 12 percent. Colder temperatures or higher wind speeds would result in larger savings due to windbreak protection. _Table 2. Animal windchill chart. As temperatures decrease and wind speed increases the danger to animals becomes greater._ chart: animal windchills breakcha.gif" Zone 1 Little danger to mature animals Zone 2 Increasing Danger; will freeze exposed flesh such as teats and scrotums; will stress animals causing latent diseases to appear. Zone 3 Great danger especially to young animals. Adapted from John Herrick, Iowa State University, Extension Veterinarian Researchers at Purdue University found that energy requirements for cows in good condition increased 13 percent for each 10 degree drop in windchill temperature below 30 degrees. A similar study in Iowa on calves and yearlings indicated that requirements for feed were 7 percent greater for those in open lots than for similar animals with shelter. Studies in Montana indicated that during mild winters, beef cattle sheltered by windbreaks gained an average of 34 to 35 pounds more than cattle in an open feedlot. During severe winters, cattle in feedlots protected from the wind, maintained 10.6 more pounds than cattle in unprotected lots. Other types of livestock also benefit from shelter. Milk production in Holstein and Jersey dairy cattle declines at air temperatures below 35 degrees. The amount of decline is dependent on animal health, coat condition, and feed intake. Under windy conditions further declines in production or increased feed requirements can be expected, due to lower windchill temperatures. Swine are poorly adapted to cold temperatures and when raised in open confinement in northern areas are subject to serious temperature stress. Windbreak protection provides significant benefits to producers in reduced feed requirements, increased weight gains, and improved animal health. When raised in confinement buildings with controlled temperatures, windbreaks reduce the amount of energy necessary to heat the confinement building. Sheep are naturally adapted to cold climates and generally receive little benefit from shelter. Two exceptions are worth noting. During severe blizzards, in areas with little natural cover, windbreaks provide valuable protection for the flock. Newborn lambs are especially vulnerable to cold temperatures and suffer significant mortality under cold, windy conditions. Providing wind protection can significantly reduce these losses. _Table 3. Increased maintenance energy requirements for cattle at temperatures below the critical temperature. For each degree (Fahrenheit) of cold, feed requirements are increased. _ _Beef Animal _Description_ _Percent Increase per degree (F)_ Weight (lbs)_ 440 _Summer coat or wet_ 2.3 660 _Summer coat or wet 2.1 880 _Summer coat or wet 2.0 1100 _Summer coat or wet 2.0 1210 _Summer coat or wet 1.9 1320 _Summer coat or wet 1.9 440 _Fall coat_ 1.5 660 _Fall coat_ 1.4 880 _Fall coat_ 1.4 1100 _Fall coat_ 1.3 1210 _Fall coat_ 1.3 1320 _Fall coat_ 1.3 440 _Winter coat_ 1.2 660 _Winter coat_ 1.1 880 _Winter coat_ 1.1 1100 _Winter coat_ 1.0 1210 _Winter coat_ 1.0 1320 _Winter coat_ 1.0 440 _Heavy winter coat_ 0.7 660 _Heavy winter coat_ 0.7 880 _Heavy winter coat_ 0.7 1100 _Heavy winter coat_ 0.7 1210 _Heavy winter coat_ 0.6 1320 _Heavy winter coat_ 0.6 Adapted from D.R. Ames, Kansas State University. Summer Protection If a windbreak is designed properly, it can protect livestock from cold winter winds and still allow summer winds to circulate in the feedlot or pasture area, reducing potential heat stress to the animals. In the North Central region where winter protection of livestock is most critical, northerly winds predominate during the winter and early spring. Locating windbreaks on the north and west sides of livestock operations provides winter protection on the south and east sides of the windbreak system. In contrast, summer winds are generally southerly, and since wind speed reductions on the windward side of windbreaks (the side towards the wind) are limited, livestock benefit from the southerly winds. By locating feed bunks 75 to 125 feet south of the inside row of the windbreak you avoid both winter and summer problems. In the winter, the access road and feeding apron will be located beyond the area where snow will accumulate. In the summer, cattle will rarely experience significant heat stress since they are outside the area of significant wind speed reduction. During the summer, livestock will seek shade if it is available. While grazing hardwood forestland is generally unwise, planting scattered hardwood trees in pastures (10 to 20 per acre) can provide significant benefits to livestock. If possible, these trees should be fenced to reduce damage to the tree. A mixture of a tall, fast growing species such as poplar, and a slower growing species such as oak, can provide shade both quickly and over the long term. Increased Yields Hay and pasture yields increase in the same way that grain crop yields increase. Water loss by evaporation is reduced when wind protection is present and more moisture is available for forage production. Windbreaks also increase production on rangeland sites with irregular rainfall because of protection from evapotranspiration by the wind. In addition to reducing moisture loss, windbreaks protect plants from physical injury. Hay yields of mixed grasses and legumes were 20 percent higher during 14 years of comparisons between protected and unprotected sites. Young alfalfa seedlings have a very low tolerance to wind and wind blown soil, and stand establishment is improved with windbreak protection. For additional information on crop response to shelter see EC 91-1765, Field Windbreaks. Snow control Optimum snow control allows easy access to animals, buildings, and forage and grain storage facilities during the winter months. Windbreaks are an effective tool which aid in protecting these travel lanes. A well designed windbreak system will collect snow in low-use areas and keep it out of high- use areas. This saves on fuel expense, reduces wear on equipment, and saves on the amount of labor required for snow removal and livestock feeding. Windbreaks can also be designed to collect snow for spring stock pond recharge and soil moisture. As collected snow thaws in the spring, the melted water can be managed for pasture or hay land irrigation down stream, or distributed across a field providing uniform spring soil moisture. Working Environment Windbreaks improve the working environment around feedlots, barns, and pasture areas. In the summer, windbreaks provide shade and guide summer breezes to minimize heat stress. In the winter, windbreaks reduce heat loss from barns and block cold winds. People are even more sensitive to windchill than livestock. When wind speeds of 20 mph are combined with an air temperature of 10 degrees, it feels like 24 degrees below zero. More seriously, a temperature of minus 20 degrees combined with a wind speed of 20 mph equals a windchill of minus 67 degrees, cold enough to freeze exposed flesh in less than a minute, making outside work more difficult and dangerous. A moderately dense windbreak will reduce the 20 mph wind to approximately 5 mph out to a distance of 5H (H = effective height of the windbreak), and wind chill to minus 26 degrees, still very cold but not nearly as dangerous. Screen Unsightly Areas Windbreaks can screen unsightly areas around the farm from the road and living area. They filter dust from tillage operations or roads and buffer traffic or machinery noise. Some odors are absorbed by plants within the windbreak while others are masked by the more desirable smells of aromatic leaves or flowering shrubs. Conifers not only provide good wind protection, but add winter color to the farmstead. Wildlife Habitat Livestock windbreaks provide sites for nesting, feeding, singing, and breeding for many birds and animals. In addition, they provide shelter from severe weather and protection from predators. By using a variety of tree and shrub species, you can attract a greater diversity of wildlife to your farm or ranch. More information on enhancing wildlife can be found in EC 91-1771, Windbreaks and Wildlife. Designing Your Windbreak Windbreaks can be designed to protect a feedlot, pasture, or forage production area. They should be located perpendicular to the prevailing winter winds (Figure 1). For example, in the Upper Midwest and Northern Great Plains, windbreaks should be located on the north and west. In some situations, an additional windbreak on the south side will provide protection from snow storms in late winter and early spring. Be careful that windbreaks located on the south side do not block summer breezes, increasing heat stress. In southern locations, windbreaks on the south should be avoided. _break1.gif Figure 1. Farmstead diagram showing windbreak locations in relation to buildings and feedlot. Your design should include proper drainage for melting snow and access to public roads and adjacent pastures or fields._ Source: Minnesota Department of Natural Resources Proper drainage for melting snow must be provided in order to reduce the level of mud in feedlot areas. Likewise, runoff from the feedlot should be directed away from the trees since the high nitrate levels of the runoff will damage the windbreak. There are two major types of windbreak designs generally used for livestock confinement areas; the traditional multi-row design and a newer twin-row, high-density design. Which design you choose depends on the area available for planting, the area to be protected, and what the windbreak is supposed to accomplish. diagram: wind zones break2.gif _Figure 2. Wind reduction zones of a multi-row windbreak. H = windbreak height. Windbreak density = 60-80%. Wind speeds in protected zones are expressed as a percent of open wind speed. For more details, see EC 91-1763, How Windbreaks Work._ The length, height, and density of a windbreak determine the area that is protected. In general, the protection provided by a moderately dense windbreak (60 to 80 percent density) will extend downwind a distance of 15H, where H equals the height of the windbreak (Figure 2). The Multi-Row Windbreak Design The traditional livestock windbreak design incorporates three or more rows of trees and shrubs, at least one of which should be a dense conifer. Typically, within-the-row spacings are from 6 to 15 feet for deciduous trees, 6 to 20 feet for conifers, and 3 to 6 feet for shrubs. Spacing between rows is typically from 12 to 16 feet but should be adjusted to accommodate the tillage equipment used to maintain the planting. The multi-row windbreak design provides a high density planting, a large area of protection and valuable wildlife habitat. Twin-Row, High-Density Design The twin-row, high-density design utilizes closer spacings, both within the row and between rows, than the multi-row design (Figure 3). Spacings are 3 to 4 feet between shrubs and 6 to 10 feet between trees, with 5 to 6 feet between tree rows. A second, and possibly a third, pair of rows may be located 25 to 50 feet from the first. This larger spacing between double rows makes room for snow storage and provides an access route to the interior of the windbreak. The area between double rows can be cropped, used for a garden area or left for wildlife habitat. cross-section: windbreak for wind and snow protection break3.gif" _Figure 3. Cross-section of a feedlot windbreak designed for wind and snow protection. The distance between the area needing protection and the windward row varies with the amount of space needed for snow storage. A. Traditional multi-row windbreak with a trip-row of shrubs on the windward side. B. Modified twin-row, high-density windbreak._ Many species have been used in this design such as green ash, ponderosa pine, eastern red cedar, and Rocky Mountain juniper. The two major advantages of the twin-row design over the single-row windbreak are: 1) greater density within a shorter timespan and 2) less weed control maintenance between rows. One disadvantage of the design is that, due to the close spacing, renovation of the windbreak may be required earlier in the lifespan of the windbreak. A combination of both the multi-row and twin-row designs can be used around feedlots and other production areas. A twin-row planting of closely spaced shrubs, 50 feet from the windward side of a multi-row belt will act as a snow trap, depositing snow between the two tree plantings. Again, be sure to provide proper drainage for melting snow. A windbreak designed to protect livestock must take into account a number of different factors and should be designed to meet the specific needs of the site, the farm operation, and the land owner's preferences. The complexity increases when additional benefits or objectives are involved. For help in designing a livestock windbreak or for further information on other types of windbreaks, contact your local Cooperative Extension office, the Soil Conservation Service or State Forestry agency. EC1766 mailto:pubs@unl.edu?subject=Comments from EC1766 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. This series of windbreak publications is jointly sponsored by the University of Nebraska, USDA Natural Resources Conservation Service, USDA Forest Service, North Dakota State University, and the Forest Stewardship Program of The Nebraska Forest Service. Its goal is to encourage the proper management of all our woodland resources. http://www.ianr.unl.edu/pubs/forestry/ec1767.htm Windbreaks For Rural Living, EC 91-1767 This publication discusses how well-designed windbreaks benefit feedlots, livestock pastures, and calving areas." University of Nebraska Extension EC91-1767-X By Bruce Wight, Soil Conservation Service, Teresa K. Boes and James R. Brandle, University of Nebraska rural-1a.jpg photo: farmstead windbreak rural-1.jpg In many parts of the United States, the constant force of the wind exaggerates daily weather conditions and can make living in these areas seem unbearable. A well-designed windbreak around the home, ranch, or farmstead slows the wind and improves the overall environment. Farm and ranch windbreaks conserve energy, provide snow control, improve working and recreational environments, enhance wildlife populations, provide visual screening and dust control, and increase the production of various wood and food products. _A well-designed farmstead windbreak can add value to your home and provide an enhanced living environment for you and your family._ Photo: USDA-SCS Ranch and farmstead windbreaks provide the greatest benefits in areas with high winds, large amounts of snow, extreme temperature fluctuations, or minimal natural forest cover. Traditionally, the most extensive use of ranch and farmstead windbreaks in the United States is in the Western, North Central, and Great Plains regions. However, windbreak use for privacy screens, dust control, and noise reduction as well as wind protection are important throughout the country. Benefits of Farmstead Windbreaks Energy Conservation Well-designed windbreaks can cut energy costs as much as 20 to 40 percent. Individual savings depend on local site and climatic conditions, the construction quality of your home, your living habits and the design and condition of your windbreak. rural-2a.jpg isolated farmstead w/windbreak rural-2.jpg _A farmstead windbreak is often a woodland island among large expanses of agricultural crops._ Photo: J. Brandle Local wind conditions affect the amount of energy needed to keep a home comfortable during cold winter months. Unprotected buildings, buildings with poorly fitted doors and windows or frequently opened doors, and buildings in areas with high average wind speeds coupled with low average temperatures are left vulnerable to winter's extremes. Windbreaks reduce the force of the wind on the exterior surfaces of buildings and thus the amount of cold air that enters the home. In the summer, the inside and outside temperatures of a home may be very similar. Usually, this means that the reduction of hot air entering the home provides only minimal savings in home cooling costs. However, in areas where hot winds are common and most homes are air-conditioned, a reduction of hot air infiltration into the home can reduce air conditioning demands and likewise energy consumption. Additionally, trees provide significant evaporative cooling and may lower the local air temperature several degrees. Well-placed landscape plants, such as shade trees or foundation plantings can provide summer energy savings of 15 to 35 percent. Snow control Winter storms on open and unprotected land can render a farmstead snowbound. A properly placed windbreak can reduce or eliminate snow drifts on driveways, in service areas, and around buildings. Valuable time and energy can be spent on other activities instead of snow removal. For additional information see EC 91-1770, Windbreaks for Snow Management. Improved living and working environments Struggling against the wind makes hard work seem even harder. Protecting working areas around the farmstead or ranch with windbreaks makes tasks such as cutting firewood, working on equipment, or feeding livestock safer and more comfortable. When winter winds are combined with low temperatures, the resulting windchill may create dangerous working conditions. For example, the cooling effect of a 15 mph wind combined with a temperature of 10 degrees affects your body warmth as much as a temperature of 18 degrees below zero. More seriously, a temperature of minus 20 degrees with a wind speed of 20 mph equals a windchill of -67 degrees, cold enough to freeze exposed flesh in less than a minute. A moderately dense windbreak will reduce the 20 mph wind to approximately 5 mph out to a distance of 5H (H = effective height of the windbreak), still very cold but not nearly as dangerous (Table I). wind chill index rural-3.gif _Wind speeds greater than 40 MPH have little additional chilling effect._ _Table I_. The wind chill index was developed to help indicate how much heat a person would lose under different combinations of temperature and wind speed. As wind speeds increase, the evaporation rate from the skin surface increases and the body experiences dramatic and often very dangerous cooling._ A farmstead windbreak can improve living conditions by screening undesirable sights, sounds, smells and dust. Reduced wind speed on the leeward side of a windbreak helps reduce the odors and dust carried from upwind livestock corrals, feedlots, fieIds and roads. Some odors are absorbed by the plants within the windbreak while others may be masked by the more desirable smells of aromatic leaves or flowering shrubs. Windbreaks reduce traffic noise from nearby roads and highways by deflecting sound off of large branches and tree trunks and by absorbing sound with leaves, needles, twigs, and smaller branches. In addition, trees and shrubs can mask undesirable noises by creating more desirable sounds such as the rustling of leaves or the singing of birds attracted to the windbreak. Garden and recreational environments A home garden not only provides healthy, homegrown produce but saves money and brings pleasure to its caretaker. Locating the family garden within the sheltered zone of a windbreak improves the yield and quality of its contents. Lower wind speeds reduce damage to tomatoes, peppers, leaf lettuce, peas, beans and other garden vegetables. Bee activity is increased, resulting in more complete pollination and fruit formation. The moderation of the microclimate by the windbreak results in early maturity of many crops such as asparagus, tomatoes, sweet corn, cucumbers and melons. Landscape plants and flower gardens also benefit from protection against hot, dry, summer winds. Recreation is an essential part of family life. Popular activities such as a picnic or barbecue in the backyard, playing ball with children, or working in the garden are far more enjoyable behind the shelter of trees. The very presence of various trees and shrubs on a ranch or farmstead attracts native wildlife, and in turn, can promote a greater awareness and understanding of nature by the entire family. Windbreak protection enriches the comfort and enjoyment of outdoor activities. Wildlife habitat Farmstead windbreaks provide sites for nesting, feeding, singing, and breeding for many birds and animals. Additionally, windbreaks furnish a safe, linear corridor for wildlife movement between feeding, watering, and resting sites. Using varied tree and shrub species you can create a smorgasbord of seeds, nuts and fruits. By including a greater diversity of food types and habitat in your windbreak you will attract a greater variety of birds and animals to your backyard. By selecting species that will provide benefits in early spring and late fall, you provide a rest area for many migrating birds. See EC 91-1771, Windbreaks and Wildlife for additional details on enhancing wildlife with windbreaks. Products from the windbreak In addition to providing protection from the wind, ranch and farmstead windbreaks can provide posts, poles, rough lumber, and firewood. These products may be useful on the ranch or farm, or may be sold for additional economic benefits. In some situations and on sites with deep, well-drained and fertile soils, high quality timber may be incorporated into the windbreak design. Species such as walnut, oak and pecan can be grown in many areas. Harvesting wood products from the windbreak requires careful management and you should seek technical assistance from a forester. Remember, it is the overall structure of your windbreak that provides protection against the wind, and it must be maintained in order to gain the benefits from your windbreak. Planting fruit and nut trees on the leeward side of a windbreak provides another opportunity for harvesting produce from the windbreak. These products are suitable for home use and possibly for sale. A windbreak creates an excellent environment for a bee operation, which in turn provides pollinators for vegetables and fruit trees and honey for home use or sale. Designing your windbreak Understanding windbreak benefits and how they are derived can help you in designing one to meet your particular needs. The primary effect of a windbreak is the reduction in wind speed in adjacent areas. Within these areas the reduction in wind speed creates zones of protection where the microclimate is improved. For multiple-row, farmstead windbreaks the zone of maximum protection lies approximately 2 to 7H to the leeward side of the windbreak (H equals the mature height of the windbreak). Additional protection is found from 1 to 3H to the windward side. The goal in designing windbreaks is to take advantage of these zones of protection to achieve your objectives. A ranch or farmstead windbreak needs to provide maximum protection to the major buildings and the living and working areas of your farm or ranch. Ideally, the windbreak row with the tallest tree species should be approximately 2-5H from all primary objects or areas needing wind protection. In regions needing both wind and snow protection, the most windward row needs to be 100 to 200 feet from the areas needing protection in order to provide room for snow drifts. Areas and objects more than 10H from the windbreak will receive little protection from the wind. Once the site of the windbreak is determined, the soils need to be examined. For the best windbreak, choose trees and shrubs suitable for your soil and climate conditions. Species native to your area are usually the best choice. Include a variety of species and at least one or two tall tree species to provide maximum wind protection for the site. By using a mixture of deciduous trees, conifers, and shrubs, the windbreak will provide better protection all year and will lessen the chance of insects or diseases damaging the entire windbreak. sketching a windbreak plan rural-4.gif _Figure 1. A windbreak is a long-term investment, and careful planning can improve benefits and help avoid future problems. A sketch of the area helps in planning. Begin by identifying prevailing or troublesome winds. Locate existing buildings, property lines, existing trees, soil problems, roads and utilities, and finally add distances to your sketch. Consider having utility lines such as electric and telephone buried to allow flexibility in design. Question marks represent dimensions you must be aware of as you design your windbreak._ windbreak design rural-5.gif _Figure 2. A) A basic farmstead windbreak consists of three to eight rows of both conifers and deciduous trees. Conifers or shrubs should be located on the windward side with the tall deciduous species in the center. A row of shrubs on the interior or leeward side completes the design. Spacing between the rows is typically 12 to 16 feet but can be increased to accommodate larger tillage equipment. Spacing within the rows is typically 3 to 6 feet for shrubs, 6 to 15 feet for deciduous trees, and 6 to 20 feet for conifers. B) In areas with frequent heavy snows consider adding a row or two of shrubs 50 feet to the windward side to trip snow before it reaches the main windbreak._ A basic windbreak will reduce wind speed, but a personalized, multiple-use windbreak designed to consider wildlife enhancement, and/or fruit, nut, and wood production will provide additional rewards. The unique attributes of some species provide accents in windbreaks that are especially pleasing when visible to the landowner. Consider what you want your outdoor living area to look like and add species that have flowering, fruiting, form, color, or texture characteristics which appeal to you. Enhanced aesthetic quality and a more natural look can be achieved by using curved rows or adding clumps of trees or shrubs to the planting. Throughout the United States, strong winds can make living in rural areas difficult. Strategically planted trees and shrubs will provide protection against the wind and will diminish both its direct and indirect effects upon people, plants, property, and animals. Windbreaks enhance the quality of life on ranches and farms and add to the value of the property. A windbreak providing only wind protection is fairly simple to design, but the complexity increases when including additional benefits such as snow control or enhanced wildlife habitat. The requirements and objectives of the ranch or farm owner will always determine the parameters of the best windbreak design to use. For additional information, see other guides in this series or contact your local Cooperative Extension office, the Soil Conservation Service, or State Forestry agency. EC1767 mailto:pubs@unl.edu?subject=Comments from EC1767 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. http://www.ianr.unl.edu/pubs/forestry/ec1768.htm Windbreak Management, EC96-1768-X This publication discusses how to maintain windbreaks, including weed control, corrective pruning, insect and disease monitoring, replanting, and the proper use of chemicals. University of Nebraska Extension, EC96-1768-X By Craig Stange, Natural Resources Conservation Service, USDA and James R.Brandle, Forestry, Fisheries and Wildlife, University of Nebraska winman1a.jpg hoeing weeds in windbreak winman1.jpg The windbreaks on your farm are an important part of the agricultural landscape. They provide protection for the farmstead, livestock, and crops; provide habitat for wildlife; and contribute to an overall healthy environment for you and your family. They are living systems with youth, maturity, and old age. Like any other living thing they need proper care and management in order to continue to function at their best. _Weed control comes in many forms--chemical, mechanical, or fabrics. For many situations the old fashion hoe still provides the best weed control possible. Photo: USDA-NRCS Windbreak management requires an understanding of how your windbreak works. Your goal is to maintain the health and vigor of individual trees and shrubs while maintaining the overall structure of the windbreak as an effective wind barrier. To accomplish this goal, practices such as weed control, protection from large animals and rodents, corrective pruning, insect and disease control, and proper chemical use in nearby fields and farmstead areas need to be included in your management plan. With proper care, a windbreak will serve a long life of protection while providing wildlife habitat and adding beauty to the landscape. Windbreak Health and Vigor Weed Control Grasses and weeds compete with trees and shrubs of all ages for moisture, light, and nutrients. For optimum tree health, competing vegetation should be managed throughout the life of the windbreak. The level of management is determined by the age of the windbreak, climate and soil conditions, and the objectives for the windbreak. While it is difficult to make specific recommendations for all areas and conditions, new plantings generally require more extensive weed control than older plantings. As your windbreak matures its potential value for many species of wildlife increases and understory vegetation becomes a critical part of its habitat value. By careful design, species selection, and management a practical compromise between total weed control and maximum wildlife habitat is achieved, resulting in both a healthy windbreak and excellent habitat. New plantings New plantings are particularly sensitive to drought conditions. Good soil moisture during the first growing season usually assures good root growth and increases the survival of the young seedlings. Over the next several years, weed competition should be kept to a minimum. In dry areas where growing season moisture is limited and on sites where wind erosion is not a problem, it is generally best to control grasses and weeds both within the row and between the tree rows of your windbreak for the first three to five years after planting. While vegetation between the rows does not compete directly with newly planted seedlings, it provides a seed source for invasion of the tree row and makes weed control within the row more difficult. In areas with adequate moisture, mowing may be used to control vegetation between tree rows. Mechanical cultivation two or three times during the growing season eradicates most annual and biennial weeds and suppresses perennial vegetation. Shallow cultivation (no more than two to four inches) when weeds are small is best since deep cultivation near the trees can destroy many feeder roots and waste soil moisture. Each cultivation loosens and dries the soil and prunes small feeder roots in the tillage zone. Care must be taken to avoid over- cultivation and mechanical injury to trunks and limbs as the trees grow. Discontinue cultivation by late summer to slow tree growth and prepare the plants for hardening before winter. Root pruning late in the growing season stimulates tree growth and retards dormancy, which may lead to winter injury. Annual weeds which appear late in the season offer little competition and may be left until spring. In addition, the standing vegetation will trap snow, reduce abrasion of the new trees by windblown soil, and reduce spring erosion. Avoid clean cultivation between the rows on soils prone to wind erosion. Instead, plant an annual cover crop such as corn, sorghum, or sudan grass between the windbreak rows and an each side of the windbreak to control soil erosion and protect the soil and young plants from the wind. These strips will trap snow, providing moisture to the new windbreak and valuable food and habitat to wildlife such as pheasant and quail. Conifers, in particular, benefit from the winter wind protection provided by these strips. As the windbreak matures, these between-the-row vegetation strips should be reduced in size and eventually eliminated to reduce competition with the expanding roots of the trees. Chemical weed control is another effective measure to eliminate competing vegetation, especially within the tree rows where cultivation may be difficult. Herbicides are relatively inexpensive and a single application usually lasts longer than mechanical cultivation. The application of a pre- emergence herbicide will reduce germinating weed and grass seeds. On established or perennial grasses and weeds, it may be necessary to use a contact or translocating herbicide. Remember, herbicides also kill or injure trees and shrubs and should be used with caution. Read and follow label directions carefully, wear the appropriate protective clothing, and protect sensitive plants during application. winman3a.jpg new planting with woodchip mulch winman3.jpg _Wood chip mulches are an attractive alternative to cultivation or herbicides and provide good soil moisture conservation and weed control. Mulches, such as wood chips, can reduce weed competition around trees and shrubs, moderate soil temperatures, and help retain soil moisture during dry periods. Mulches help you see the trees and reduce the potential for injury when mowing or cultivating the rest of the windbreak area. Place a three-to four-inch thick layer of mulch around trees and shrubs immediately after planting, and maintain it for a minimum of five years. Keep the mulch three to four inches away from the stem of the tree or shrub to reduce small rodent damage. Avoid using hay or straw as these tend to attract small rodents which may damage the young seedlings. In regions of low rainfall, woven, black plastic weed barriers are effective in reducing weed competition and soil moisture loss in new windbreak plantings. They come in several sizes and thicknesses. Small squares (typically three feet by three feet) and continuous strips (six to eight feet wide) are most common. When properly installed, these landscape fabrics last five to ten years and significantly reduce weed control efforts during this period. Although they reduce the workload associated with weed control, they are not maintenance free. Weeds still occur between the rows and along the edge of the fabric and care must be taken to avoid damage to the fabric when mowing or cultivating. While the initial cost of fabric mulch is higher, its long life makes it cost-competitive with other weed control practices. When selecting a fabric mulch, look for one that is resistant to ultraviolet light with a guaranteed life of at least five years. winman2a.jpg new planting using landscape fabric winman2.jpg _Landscape fabrics reduce the labor required for weed control and offer many advantages in dry or remote areas where other measures are impractical. Installing individual squares is fairly easy, but the long continuous strips require a fabric-laying machine and are best installed by someone with experience. The fabric should be tight and well anchored to prevent the wind from tearing or blowing the fabric off of the site. It is best to apply fabric on cool, cloudy days but this is not always practical. Best results are obtained when someone follows the laying machine and immediately releases the seedlings from under the fabric. Studies have indicated that on sunny days, temperatures under the fabric may exceed 160 deg F or more within minutes even when air temperatures are quite cool. Temperatures in this range will stress the young seedlings and under some conditions even kill young seedlings in less than five minutes. Mulches and landscape fabrics provide consistent weed control throughout the growing season and eliminate the need to find time to control weeds mechanically several times a year. When moisture is limited, mulches and landscape fabrics effectively reduce moisture loss and weed competition, increasing seedling survival. Older plantings Older plantings benefit from good weed control, too. The control of competing vegetation within the tree row will increase growth rates and reduce the time needed to produce an effective windbreak. Within the row, weed control should continue as long as practical but typically for five to ten years following planting. Beyond 10 years, weed control should focus on reducing the presence of noxious weeds and sod forming grasses. Grasses such as smooth brome, quack grass, or crested wheat grass can choke the life out of an otherwise healthy windbreak and should be controlled. Effective sod control throughout the life of the windbreak can add decades to its useful life. Remember that total removal of all ground vegetation will severely reduce the wildlife value of the windbreak and increase the potential for erosion damage. winman4a.jpg herbicide use in maturing windbreak winman4.jpg _Sod forming grasses compete for moisture and nutrients and reduce tree growth rates. In older windbreaks contact herbicides are an effective control method. As a windbreak matures there is a natural tendency for the lower portion of the trees to die back, decreasing density. In order to maintain an effective structure some type of understory vegetation is necessary. Native trees and shrubs are best and often become established naturally. While some species such as thorny honey locust may be a concern, other species such as cedar, honeysuckle, dogwood or mulberry provide valuable food and cover for wildlife. If regeneration does not occur naturally, it may be necessary to interplant shade tolerant shrubs to enhance the understory structure. When windbreaks contain conifers and suckering shrubs, weed control should become more selective. As conifers mature, they will provide shade and a carpet of needles that will effectively control most weeds. Tillage practices should be discontinued in these areas to allow this natural weed control method to become fully established. In some cases, spot spraying or hoeing may still be necessary in order to control sod-forming grasses or noxious weeds. Suckering plants should be allowed to sucker and fully occupy the site providing they do not reduce the effectiveness of the windbreak. A thicket of sprouts will effectively control most weeds with shading but may increase windbreak density to the point of causing deep snow drifts in some locations. Protection from Animals Livestock benefit from the protection provided by a windbreak; however, grazing livestock within the windbreak will cause serious damage to your investment. Damage from trampling, browsing, and breakage leads to slower growth, weakened trees, and premature death. When livestock congregate near trees, soil compaction can cause problems by limiting the amount of water and oxygen available to tree roots. All windbreaks located in areas where they may be subject to grazing should be fenced. Effluent from concentrated livestock operations can kill individual trees and over time, entire sections of the windbreak may be lost due to the high nitrate content of the feedlot runoff. This damage can be prevented by properly locating the windbreak, installing drainage ways to safely remove runoff from the feedlot, and by constructing waste holding facilities as needed. Wild animals, particularly deer, rabbits, and mice are more difficult to control. In young plantings, repellents, traps, and placing mesh guards around seedlings will provide some control. Fortunately, older plantings are not as sensitive to damage by wild animal feeding. In fact, many landowners are interested in attracting wildlife to their land and careful management can provide significant wildlife habitat benefits. Consult your http://ffw1.unl.edu/nfs/forbrochure.html">local forester or wildlife biologist for safe and effective methods for controlling or attracting wildlife. Pruning Resist the urge to prune windbreak trees to look like residential yard trees. Pruning live branches from older trees will decrease density and reduce the efficiency of the windbreak. Remember that the effectiveness of a windbreak is dependent on the overall structure of the windbreak and not on the shape of any individual tree. Although good windbreak management may require pruning under some circumstances, the best rule of thumb is to avoid pruning windbreak trees unless there is a very specific reason to do so. Branches damaged by ice, wind, animal grazing, or bird roosting should be removed. Damage to the central leader of a conifer causes the lateral branches to assume the role of the central leader and begin to grow upward. If left to grow, a double leader may develop, creating a weak spot in the trunk as the tree matures. Forked and multi-stemmed trees are prone to wind breakage, and don't grow as tall as single stem trees. However, before they are removed make sure the structural integrity of your windbreak will be maintained after removal. Pruning is often regarded as a labor intensive effort, but when required, it pays off in a healthy windbreak. A yearly inspection to look for and prune damaged or deformed trees will keep the task manageable and will contribute to a long-lived, healthy windbreak. Pruning on a regular basis, generally in late winter, will reduce the likelihood of an expensive pruning or salvage effort later in the life of the windbreak and may limit storm damage. If done on a regular basis, effective pruning can be done with hand clippers and a small pruning saw. A clean cut will heal quickly, reducing the potential of invasion by insects or fungi. Make the cut just outside the swollen branch collar at the base of the branch. If large limbs must be removed, make a small undercut first immediately below the final cut, to prevent the weight of the falling branch from tearing the bark on the trunk. When pruning trees suspected of harboring diseases, all pruning tools should be sanitized after each cut with a solution of one part chlorine bleach and 10 parts water. This will reduce the likelihood of spreading disease to healthy limbs or trees. In some agroforestry applications involving high value hardwoods, pruning to improve sawlog quality may be an integral part of windbreak management. Under these conditions additional plantings of shrubs or conifers may be required in order to increase the density of the lower portion of the windbreak. Insects and Diseases Insects and diseases are not usually a problem in healthy trees. Trees that are under stress and growing slowly or losing vigor because of weed competition or animal damage are more susceptible to insect and disease problems. Frequent inspection and alertness in recognizing the early stages of injury from insects and diseases will make correction of the problem easier. Walk through your windbreaks each spring and fall. If control measures are needed, consult your local conservation or extension office for the best control methods. Herbicides Many windbreaks are planted to protect agricultural operations which may require the use of various herbicides. Trees and shrubs in your windbreak may be sensitive to the herbicides applied to nearby fields or lawns. Multiple exposures each year to damaging chemicals may cause stress, increasing the risk of insect damage or disease and reducing the effective life of a windbreak. Be aware of wind conditions that may cause herbicides to drift and exercise caution when applying herbicides in or near your windbreak. Fertilization In most cases, your trees will not require fertilization. Over- fertilization can cause rapid growth, which leads to large, weak leaders and reduced density. Fertilization late in the season slows the onset of dormancy and may lead to winter injury. If you suspect that your soils are low in a critical nutrient be sure to have a soil test done before applying fertilizer. Structural Management The old saying, "You can't see the forest for the trees," is often the case when people look at a windbreak. People still tend to look at the shape or form of individual trees within the windbreak and expect those trees to look the same as a tree in the front yard. But in a windbreak situation it is the structure (the amount and arrangement of the leaves and branches) of the entire windbreak that determines its effectiveness. Trees are selected and planted close together in order to create a windbreak with a desired structure capable of meeting your objective. Just as the health and vigor of a windbreak requires management, so may the overall structure of a windbreak require care. The best time for structural management decisions is during the planning stage. Decisions on species selection, number of rows, and spacing determine the future density of the windbreak and are the most important aspect of structural management. Planting trees close together will provide protection in a shorter period of time but may result in a windbreak that is too dense for your objective and may lead to higher levels of insect and disease problems. Planting trees too far apart may result in little or no protection. As trees grow, the relationships among them change. The density and position of tree crowns change in relation to height above ground and neighboring trees. Most of these changes are small and with good planning your windbreak will continue to meet your objectives. Occasionally, these changes may affect the overall windbreak structure to the point that the windbreak no longer meets your objectives. In this case some type of structure management may be required. For example, if the windbreak is too dense, structure can be significantly altered by careful tree removal. Similarly, if the windbreak is not dense enough, interplanting or underplanting may be needed. This type of management is very tricky and it is extremely important to keep your objective in mind. It is best to get the advice of an expert before undertaking this type of windbreak management. Fencerow Windbreaks winman5a.jpg fencerow windbreak winman5.jpg _In many areas fencerows have grown up with native trees and shrubs. Instead of removing these trees, they can be managed to provide excellent windbreaks. Photo: D. Berne A unique opportunity occurs when fencerows containing trees and shrubs are properly managed. Careful selective cutting within a fencerow can convert it to an effective field windbreak. Most native species of trees and shrubs are suitable for retention in a fencerow that is being modified into a windbreak. When making selections, favor species that are long-lived, disease resistant, breakage-resistant, and have dense crown development, such as oaks, ashes, hard maples, and eastern redcedar. If possible, trees should be left every 10 to 16 feet and in a relatively straight line. If gaps occur, plant the open spaces with small saplings of the most common species in the row. You may also try planting nuts or seeds of desired species. It is a good idea to plant more trees than are needed, especially if you try direct seeding, since survival rates may be low due to the high degree of competition that is present. This is especially true in dry regions, and in these circumstances supplemental water and weed control may be needed for the first several years. With a little imagination and common sense, a relatively low-value fencerow can be converted to a valuable windbreak investment. Summary Windbreaks are an integral part of many farming and ranching operations. All windbreaks, even well designed ones, need regular maintenance beginning the day of establishment. Regular attention to weed control, corrective pruning, insect and disease monitoring, replanting if needed, and proper use of chemicals on adjacent fields and yards will help ensure an effective windbreak for many years. A regular program of windbreak management naturally leads to consideration of windbreak renovation. Quite often the two are intertwined and indistinguishable from each other. More details on the techniques of windbreak renovation are contained in EC 97-1769 Windbreak Renovation. For copies of this and other windbreak publications in this series see your local district forester, extension educator, or district conservationist. EC1768 mailto:pubs@unl.edu?subject=Comments from EC1768 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. http://www.ianr.unl.edu/pubs/forestry/ec1770.htm Windbreaks for Snow Management, EC96-1770-X This publication discusses establishing windbreaks for effective snow management." University of Nebraska Extension, EC96-1770-X By James R.Brandle and H. Doak Nickerson Forestry, Fisheries and Wildlife, University of Nebraska snow1-a.jpg windbreaks between farm fields snow1.jpg In areas of high winds and blowing snow, windbreaks can reduce the amount of effort spent on snow management. They can be designed to spread snow across a large area or to confine it to a relatively small storage area. The design of your windbreak will depend on your objective. Field windbreaks designed to distribute snow evenly across a field should be tall and porous. In contrast, windbreaks designed to capture snow and control drifting should have multiple rows with high density. _A windbreak across a large field distributes snow throughout the field, providing winter protection and moisture for crop production. (61K JPG) Photo: PFRA There is no one set design, number of rows, or width of planting that is ideal for every circumstance. The design of your tree planting should be done with your needs and winter conditions in mind. In some cases, landowners may choose to relocate fences, driveways, or feedlots in order to take full advantage of their windbreak. Remember, a tree planting is a long-term investment and it pays to consider all alternative designs before installation. Benefits of Snow Management In areas of high winds and blowing snow, windbreaks serve the dual purposes of modifying climatic factors and providing methods for managing snow. In open areas, wind lifts, carries, and deposits snowflakes just as it does soil particles. By modifying wind flow, blowing snow can be distributed over a field or deposited within a given area. Effective snow management can yield a variety of results. A low density field windbreak will spread snow across the protected area, provide additional moisture for crop fields and rangelands, and increase productivity and economic return. Field and rangeland windbreaks reduce spring runoff partly through the physical retarding action of snowdrifts on water flow and partly through the presence of unfrozen soil under the snow cover. A dense multiple row windbreak or living snow fence will pile snow in a restricted area, reducing the need to plow highways and driveways. Dense windbreaks on rangelands provide protection for spring calving and lambing areas and reduce mortality of newborn livestock. Living snow fences located to the windward side of stock ponds deposit snow in the pond area and can provide significant amounts of water for summer use by livestock. Controlling blowing snow with windbreaks can prevent large drifts in the living and working areas of farmsteads and feedlots and reduce the labor and energy needed for snow removal. Snow Control on Fields and Pastures In areas where snow provides a critical source of soil moisture for crop and forage production during the next growing season, windbreaks help capture the moisture available in snow by keeping it on the fields. In northern prairie areas, croplands protected by field windbreaks trap blowing snow on the fields resulting in improved crop yields. On average, yields of winter wheat are increased by 15 to 20 percent. These increases are a result of increased moisture due to snow capture and to the protection of the wheat crop from winter desiccation. Design and Location Field windbreaks designed exclusively for the uniform distribution of snow across the field should have a density of no more than 40 percent. Planting a single row of a tall, deciduous tree species on a wide spacing (15 to 20 feet between trees) in a location perpendicular to the prevailing winter wind will provide good snow distribution across a field to a distance of 10 to 15 times the height of the trees. Snow blowing over the tops of the trees falls out of the air-stream on the relatively still, leeward side of the windbreak. Wind passing through a porous windbreak will distribute the snow evenly across the field. The uniformly distributed snow cover provides the opportunity for maximum water infiltration into the soil. Field windbreaks that are too dense will cause the snow to collect in narrow, deep drifts near the tree row. In more northern areas these deep drifts may cause excessive moisture in the area adjacent to the windbreak, prevent uniform and early surface drying of the land, and delay field operations. In more southerly areas, the spring thaw usually occurs early enough so that field operations can be carried out in a timely manner. In those cases where an established windbreak is too dense for effective snow distribution (60 percent density or more), removing selected trees or pruning the lower tree branches up to a height of four feet will allow more wind to pass through the windbreak and will result in a more even distribution of snow across the field. Unfortunately, pruning of deciduous trees may cause an increase in sprouting from the base of the tree, increasing windbreak density. Pruning also allows more light to reach the area around the base of the trees causing an increase in understory vegetation, and again leads to deeper snow drifts on the leeward side of the windbreak. Once pruning has been started it must be continued for the life of the planting. Remember, you are working with living plant material which may respond differently to your site conditions or actions, and it is best to seek advice from your local forester before you thin or prune your windbreak. Areas or fields vulnerable to wind erosion during the winter offer additional challenges since field windbreaks with a density below 40 percent provide little protection for the soil resource. If the field is covered with snow, the soil resource is protected; however, many areas where snow is an important source of water do not have continuous winter snow cover and therefore additional protective measures must be used. If the windbreak density is increased to provide erosion control then snow distribution is reduced, resulting in larger drifts. One solution to the problem is to use a combination of conservation practices. For example, by using a system of porous field windbreaks and conservation tillage a landowner will get both good snow distribution and good erosion control. The important aspect to remember is that any conservation practice must be designed for your conditions and farm operation. Living Snow Fences snow2-a.jpg highway and windbreak snow2.jpg _Living snow fences located along the north side of a highway will reduce time and energy costs associated with snow removal and improve winter driving conditions. In those situations where the goal of snow management is to confine the snow to a limited area, a dense windbreak of trees and shrubs can be a cost- effective method of controlling blowing snow. Living snow fences planted along highways, county or private roads, driveways, irrigation ditches, and fence lines provide economic advantages over slat-fence barriers and provide additional benefits to the landowner. Living snow fences have greater snow storage capacity, require less maintenance once they are established, have a longer life span, and provide multiple benefits such as livestock protection, crop protection, soil erosion control, wildlife habitat, and aesthetic value. Design and Location In major storms, short (3-4 feet), vertical slat fences reach their snow- storing capacity quickly. Wind-driven snow then sweeps across the saturated barrier causing drifting in the roadway and reducing visibility. In open, windy areas blowing snow often continues long after the actual snowfall has stopped. If the snow fence is already full, snow drifts may continue to develop and repeated drift removal may be necessary. Taller (12 feet) wooden barriers with horizontal boards are very efficient and store considerably more snow, but at a much higher cost. In contrast a three-row living snow fence (20 feet tall) will store the same amount of snow but at a fraction of the cost. diagram: height and density determine snow storage snow3.jpg A living snow fence achieves optimum snow storage capacity when winter density of the individual rows is about 50 to 60 percent. As density increases, drifts become deeper and shorter. Windbreaks with very close spacings, both within the row and between the rows (densities greater than 60 percent) may be damaged by deep, heavy snow drifts. Remember that density will vary with the number and spacing of the tree rows, the species chosen (evergreen vs. deciduous) and the distance between trees within the row. The height of the trees is also important since snow storage capacity increases more than four times when the height doubles. For example, a three-row, mature, living snow fence with a height of 20 feet will store over 16 times more snow than a single-row slat-fence (height = 3 to 4 feet). _Figure: The height and density of the snow fence or windbreak will determine how much snow can be stored in the system._ Species will vary depending on climate, soil, and available space and should be chosen based on local growing conditions and the objectives of the landowner. By careful design and selection the windbreak can serve additional functions, such as erosion control, wildlife habitat, and livestock protection. A living snow fence should be located perpendicular to prevailing winter winds and be placed so that the highway or area to be protected is located on the leeward side of the windbreak. In most areas, winter winds come from the northwest, north, or northeast and living snow fences should be located on the north side of east-west roads, or on the west side of north-south roads. Allow plenty of room for the leeward drift by locating the windward row of your windbreak 200 to 300 feet from the center of the road. Trees should be planted no closer than 200 feet from corners or intersections in order to allow for traffic visibility. Local ordinances may restrict the location of windbreaks for snow control, so be sure to check with the local authorities on regulations in your area. In some areas snowdrifts may accumulate on the steep, leeward slopes of roadcuts and cause serious soil erosion when the snow melts. This problem may be reduced by planting the living snow fence parallel to the ridge line about 100 feet to the windward side of the crest. The windbreak will then collect snow on the more gentle slope on the windward side of the hill, and reduce the impact of runoff caused by melting snow. Snow Control for Farmsteads and Feedlots The main objectives of farmstead or feedlot windbreaks are to reduce the force of the winter wind on the activities within the sheltered zone and to enhance the microclimate on the leeward side of the windbreak. An additional benefit of these windbreaks can be the management of blowing and drifting snow. snow4-a.jpg controlling drifts along a roadway snow4.jpg _In areas where trees and shrubs are difficult to grow, tall grass barriers can be used for distributing snow and controlling erosion. Photo: USDA _ With no windbreak protection, farm houses and other buildings act as solid barriers to the wind, resulting in swirling wind currents around corners or structures. Driveways and work areas may be subject to snow drifting, become inaccessible, and require additional hours of labor to remove the snow. A properly designed windbreak can catch and store most of the snow, reducing the need for snow removal. One purpose of feedlot and livestock windbreaks is to maintain an area relatively free from deep snow where hay and other feed are stored. These windbreaks provide a haven where livestock can get out of strong winds and driving snow. This reduces animal stress and decreases feeding requirements, resulting in better animal health, lower death losses, and lower feed costs. Design and Location Farmstead or feedlot windbreaks should be located so that the windward row of trees is at least 150 feet (300 feet in northern areas with large amounts of snow) from buildings, driveways, and feedbunks in order to provide adequate room for the leeward snow drift. This distance should allow between 75 and 100 feet from the leeward side of the windbreak and the areas needing protection. On the windward side of the windbreak, there should be at least 50 feet between the windbreak and roads or other features that might be within the zone of the windward drift. The ends of the windbreak should extend at least 100 feet beyond the farmstead or feedlot to prevent the drift which forms at the end of a windbreak from interfering with farm operations. For any windbreak designed to capture snow in high use areas, allowances must be made for controlling the runoff from melting snow. Proper drainage is critical since excess water from melting snow will result in muddy conditions which are inconvenient to the landowner and cause serious problems for livestock in feedlot operations. In the case of feedlot windbreaks, runoff from the feedlot also must be controlled and not allowed to damage the windbreak. One method of controlling snow when space is limited is to establish a single or double row of dense shrubs located parallel to the main windbreak and 50 to 100 feet to the windward side. This will provide a trip row for blowing snow, reduce the size of the snow drift in the main windbreak, and reduce potential damage to the main windbreak caused by heavy snow loads. The area between the shrub row and the main windbreak can be cropped and may be an ideal site for wind sensitive crops such as vegetables. Again, be sure to provide for the runoff from melting snow. Typical windbreaks for snow control around farms, ranches, or feedlots consist of four to six rows (a row of shrubs, two or three rows of conifers and one or two rows of tall deciduous trees). In northerly areas additional rows may need to be incorporated in order to provide adequate protection from cold winds and heavy snow. The specific designs for these types of windbreaks must be developed for individual locations and circumstances. For more information on these two types of windbreaks ask your district forester, extension specialists or conservationist for copies of the farmstead and livestock publications in this windbreak series. EC1770 mailto:pubs@unl.edu?subject=Comments from EC1770 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. http://www.ianr.unl.edu/pubs/forestry/ec1771.htm Windbreaks and Wildlife, EC91-1771-B This publication discusses how well-designed windbreaks benefit wildlife habitats." University of Nebraska Extension, EC91-1771-B Windbreaks and Wildlife By Ron J. Johnson, Mary M. Beck and James R.Brandle -- University of Nebraska http://www.ianr.unl.edu/pubs/forestry/graphics/1771-1a.jpg photo: cardinal on conifer 1771-1.jpg Windbreaks can support wildlife that add beauty and pleasure to our lives. They also sustain birds that eat insect pests, improve hunting opportunities, and provide a focal point for family outdoor activities. The world around us would be less appealing without the stimulation--the color, sounds, tracks, and mystery--of wild creatures; windbreaks help wildlife and in some areas are essential to survival of the wildlife we enjoy. You can add wildlife benefits to windbreak plantings whether your main goal is to shelter crops, livestock, roads, or a home or farmstead. _Cardinals and other non-migratory birds benefit from dense conifers that provide protection from cold winter winds. _Photo: Nebraska Game & Parks Commission. This publication provides an overview of windbreaks and wildlife, and gives examples of trees, shrubs, and planting designs to consider. However, because adapted plant types and wildlife needs vary among areas, refer to local experts for details. Personnel from Cooperative Extension, state wildlife or forestry agencies, the Soil Conservation Service, and others can help or will know how to direct you to the needed information. Why Include Wildlife in Windbreak Plans? _Insect-eaters._ Many birds and predatory insects that live in windbreaks consume pest insects in the windbreak and in adjacent crop fields. One report estimates that birds consume about 260 pounds of insects per half-mile of windbreak each year. These insect-eaters are a natural biological control that may reduce crop losses and reliance on pesticides, aspects of possible economic significance for integrated agricultural systems. _Windbreaks as an Investment in Recreation._ Studies in the Great Plains show that hunting pheasants or quail is usually more successful in areas with woody windbreak plantings. Windbreaks also benefit other game animals including cottontails, mourning doves, squirrels, and white-tailed deer. A 1985 survey by the U. S. Fish and Wildlife Service showed that, in the United States, adults spend about $55 billion each year on wildlife-related recreation. In Kansas, researchers attribute more than $30 million annually to hunting activities associated with windbreaks. The demand for outdoor recreation opportunities, such as hunting, wildlife observation, camping, photography, and hiking, is likely to continue to increase. Windbreaks can enhance these outdoor recreational opportunities. 1771-2a.jpg family in woods 1771-2.jpg _Windbreaks provide opportunities for family outdoor activities. _Photo: Kathleen E.Clement. _Families and Windbreaks._ Windbreaks on a farm or acreage can become a focal point for outdoor family activities. They provide aesthetic beauty to enhance the home or farm; a quiet setting for walks, bird watching, or overnight camp-outs together; a route for hayrack rides with wildlife to be seen; and a place for hunting or wildlife educational activities. An evening of television is soon forgotten but the memories of family adventures by the windbreak will last a lifetime. How Windbreaks Benefit Wildlife _A Place to Nest._ Shelterbelts provide nesting habitat for a wide variety of birds (Table I) and other wildlife species. At least 57 kinds of birds have been recorded using windbreaks in the United States during the breeding season. Mourning doves nest and call in windbreak trees but forage nearby for the seeds that they eat. Some birds such as the black-billed cuckoo ("rain bird"), house wren, gray catbird, and northern oriole conduct nearly all their activities within the windbreak. American robins, kingbirds, brown thrashers, and American goldfinches sing and nest in windbreaks but forage both in and out of them. Other species, including squirrels and cottontail rabbits, nest in windbreaks, and white-tailed deer with fawns use them for cover. _Food and Foraging sites._ Windbreaks provide food for wildlife as well as protective cover when they forage in adjacent areas. Foods potentially available in wind-breaks include fruits, nuts, acorns, seeds, foliage, and insects or other invertebrates. Availability of these foods varies seasonally and depends largely on what's planted or growing in the windbreak. Trees and shrubs produce fruits and some hold them into winter, a time when food is often critical for survival but generally less available. Acorns, nuts, and other seeds from trees such as elm, maple, and ash are used by wild turkeys, pheasants, quail, squirrels, deer, and songbirds. Seeds may also be available from grasses or herbaceous plants growing in the windbreak or from wildlife food plots planted within or adjacent to the woody vegetation. Foliage such as leaves or other plant parts may provide food for browsing animals such as deer. Insects and other invertebrates are important foods for many birds, particularly during nesting periods, and for various small field mice and shrews. Windbreaks provide foraging sites that would otherwise be unavailable. For example, chickadees glean along branches, peeking in and under crevices in the bark looking for insects to eat. Windbreak species such as hackberry, hawthorn, black cherry, autumn olive, honeysuckle, and others serve as nectar sources and habitat for butterflies, honey bees, and hummingbirds. Food availability near shelterbelts is also important for many species. In fact, pheasants generally don't use windbreaks, especially in winter, unless there is a nearby food source. Croplands, such as cornfields, that have waste grains, interspersed weed seeds, and insects are used by ring-necked pheasants, northern bobwhites, mourning doves, and others. Avoid autumn plowing of such croplands where possible and consider using cropping systems such as no-tillage that leave ground cover. Old field habitats or water sources near windbreaks can provide habitat requirements for some species. _Table 1. Examples of birds that benefit from shelterbelts in the United States._ Reported shelterbelt uses Bird species Feeding Nesting season Resting/Loafing Gray partridge * King-necked pheasant * * Northern bobwhite * * * Mourning dove * * Black-billed cuckoo * * * Red-headed woodpecker * * * Downy woodpecker * * * Northern flicker * * * Easternwood-pewee * * * Least flycatcher * * Western and Eastern kingbirds * * * Black-capped chickadee * * * American robin * * * Gray catbird * * * Brown thrasher * * * Warbling vireo * * * Indigo bunting * * * Dark-eyed Junco * * * Common grackle * * * Northern oriole * * * American goldfinch * * * American kestrel * * Sharp-tailed grouse * * Hairy woodpecker * House wren * * * Eastern bluebird * Northern mockingbird * Cedar-waxwing * * * Yellow warbler * * * America redstart * * Common yellowthroat * * * Yellow-breasted chat * Northern cardinal * * Rose-breasted grosbeak * * * Rufous-sided towhee * Lark sparrow * White-throated sparrow * Brown-headed cowbird * Orchard oriole * * * _Shelter From Predation - Escape Cover._ Windbreaks provide escape cover and refuge for many wildlife species. Pheasants often stay near windbreak cover while feeding in adjacent areas, and, during midday loafing periods, the woody vegetation offers refuge from people and overhead predators. In general, wider shelterbelts with a good vegetation layer near the ground offer better escape cover than do those that are more narrow and open. When planning wildlife escape cover, consider the surrounding land use. Be aware that in areas with no trees or other perches, tall deciduous windbreak trees may attract avian predators. In most situations, hawks and owls are welcome because they eat pest rodents and inspire joy and awe in many who watch them. However, in areas where no other perches exist and where enhancing pheasants, quail, or partridge is the primary wildlife goal, shrubs or moderately sized trees may be better alternatives. _Shelter from weather._ Shelter from the wind is a critical aspect of wildlife survival in winter. An animal maintains warmth by avoiding exposure to the wind, ideally in a warm sunny spot, and by fluffing feathers or fur coats. Food is vital because it is the basic source of all body heat. An animal must balance the needs of finding food against the increased exposure to wind when foraging. Windbreaks can provide both shelter and food. Shrubs and ground cover on the lee side allow animals to perch or rest out of the wind and, with many windbreaks, the lee side will have exposure to the sun. When food is available in or near the shelter, wildlife can find food without long exposure to cold wind. The combination of wind protection, food, and sun exposure can be a life saver for wildlife during critical winter times. farmstead layout 1771-3.gif _Figure 1. Planting food plots or fruit-bearing shrubs on the lee side of windbreaks provides food in an area protected from wind and possibly warmed by the sun, points that are particularly important in cold months._ Source: USDA- SCS The quality of a windbreak for protection from weather extremes relates to several factors, including the wildlife species involved; severity of the weather; age, size (length and width), density, orientation, location, and vegetation composition of the windbreak; and food availability in or near the shelter. Animals in colder climates may require larger, especially wider, plantings. Pheasants like the shade and microclimate at ground level in woody cover-- during winter for daytime loafing or resting, and, in spring, for protection from heavy rains. Reports that windbreaks become winter "death traps" for pheasants because of blowing snow have largely been discounted. The problem is not windbreaks, but lack of sufficient ground cover anywhere, in or out of the windbreak. Studies have found that pheasants generally leave deciduous shelterbelts in response to high winds and heavy snow, but during winter they may roost in coniferous windbreaks. The key for winter pheasant protection is a wide windbreak with enough space for snow storage, adequate shelter near the ground, and a nearby food source. _Travel Lanes._ Wildlife need to move about to find necessary food and other resources. The long, linear nature of windbreaks provides safe routes from one habitat to another. Species such as quail, pheasants, songbirds, rabbits, squirrels, and deer may use windbreaks as travel lanes between feeding sites, as protected cover at feeding sites, and as routes for safe dispersal. On a broader scale, they function as stopover points for migrating songbirds heading north for the summer or south for the winter, to the southern United States or even to South America. A Note of Caution for Grassland Wildlife Some native grassland birds need large unbroken areas of grass habitat with few trees and shrubs. Examples include western meadowlarks, bobolinks, dickcissels, lark buntings, grasshopper sparrows, upland sandpipers, and greater prairie chickens. Although not as familiar as some species, these are important parts of grassland ecosystems, and some are in trouble, with significant declines. Although reasons for the declines are unclear, studies do show that, near woody cover, grassland birds can be at greater risk from predation by various bird and mammal predators and from brood parasitism by brown-headed cowbirds. Other prairie animals, such as the pronghorn antelope, also may be affected. Planting windbreaks in large unbroken areas of grasslands, although helping some wildlife species, may hinder others, so plant where needed but keep in mind the possible wildlife trade-offs. What to Plant In choosing what to plant, think about what factors make a windbreak attractive to wildlife. For example, one Minnesota study of farmstead windbreaks found that most bird species primarily used the vegetation layer within two feet of the ground. The ground layer is critical in providing winter wind protection and is especially important for species that nest or feed on or near the ground. The canopy or upper layer provides many birds with sites for nesting; singing; and foraging for insects, tree seeds, and fruits. For the best wildlife benefits, a shelterbelt should have a developed tree canopy, and an understory that includes shrubs and herbaceous plants that provide both food and cover. Grasses, especially sod-forming ones, compete with young trees and should be 3-4 feet away from them during the first five years alter planting. However, during establishment, planting between rows, 3- 4 feet from trees, a mixture of short- to mid-height bunch grasses, milo, or similar cover provides wildlife benefits and protection for soil and young trees. 1771-4a.jpg screech owl 1771-4.jpg _Older and wider windbreaks provide homes for cavity-nesters such as this screech owl. Hawks and owls are predators that help keep nature's abundance in balance._ Photo: Nebraska Game & Parks Commission Choice of specific plant types will vary among locations because of climate, soil, and other factors. Think about selection because some plant species provide more wildlife benefits than others, and a variety of species is necessary to provide the range of habitat needs of most wildlife. Planting a variety of deciduous tree and shrub species will provide a habitat structure with a large selection of vertical and horizontal nesting and foraging sites. Oaks provide habitat structure and acorns produced are a top food choice for many game birds and mammals. Hackberry has branching characteristics that are preferred by many songbirds for nesting and foraging. Siberian elm is also a preferred tree for songbirds but is not a good choice for windbreaks. Crabapples are excellent nesting sites, and planting several varieties can provide both late summer and winter food. Some ash, cottonwood, maple, pine, and oak species, when mature, can provide sites for cavity nesters. Tall deciduous trees such as eastern cottonwood, maple, and ash are used by northern flickers, warbling vireos, and others for nesting, foraging, and singing, Tatarian and amur honeysuckle, chokecherry, plum, autumn olive and other shrubs are used by American robins, brown thrashers, gray catbirds, and cardinals for nesting and feeding. Conifers provide protected sites for early spring nesters, shelter for migrating songbirds, and winter roosting and loafIng sites for pheasants. The fruits on eastern redcedar and Rocky Mountain juniper also provide a winter food source for songbirds and gamebirds, and the foliage provides browse for pronghorn antelope and deer. Features of possible concern in some situations include the thorns on hawthorn and buffaloberry, and possible house sparrow use of eastern redcedar, Rocky Mountain juniper, and maples if planted next to farm buildings. Blackbirds and starlings may roost in urban windbreaks in certain regions of the United States, especially in coniferous trees, but they are less likely to do so in open rural areas. _Table II. Examples of windbreak plants that benefit wildlife and their primary wildlife values, which occur mostly during summer and fall (S), fall and winter (W), or include browse (B)._ Overall Fur & Plants wildlife Songbirds Gamebirds game mammals ^1,^2 value Nesting Food Cover Food Cover Food Cover _Conifers_ (Excellent winter cover, food, and nesting sites) Eastern redcedar Excellent * _W_ S_W_ W S_W_ B S_W_ Rocky Mtn. juniper Excellent * _W_ S_W_ W S_W_ B _SW_ Arborvitae Good - Excel * S_W_ S_W_ B S_W_ Spruce Good * S_W_ S_W_ S_W_ Pine Good - Excel ** S S_W_ S S_W_ B S_W_ Fir Fair * S_W_ S_W_ S_W_ _Deciduous trees_ (Nesting and foraging sites, food, canopy and habitat structure) Oaks Excellent * W S _W_ S _W_B S Osageorange Excellent ** _S_ S S Hackberry Excellent ** SW _S_ W S B S Pecan Fair W S W S W S Black walnut Fair W S S W S Mulberry Fair * _S_ S S S _S_ S Ash Good * W S W S B S Maple Good * S S S S B S Siberian elm Excellent ** S _S_ S S Cottonwood/poplar Fair * S S B S Black cherry Excellent * _S_ S _S_ S SB S Flowering crabapples Excellent ** _W_ _S_ _W_ S WB S Hickory Fair W S W S W S Hawthorn Good ** W _S_ W S B S Serviceberry Good * S S S S B S _Tall shrubs_ (Nesting sites, food, cover near ground) Russian olive Good * W S W S W S Autumn olive Excellent * W SW W SW W SW Honeysuckles Excellent ** W _S_W W SW WB SW Viburnums Excellent * W SW W SW WB SW Shrub dogwoods Excellent * S SW S SW B S Buffaloberry Good W SW W SW SW Staghorn & smooth sumacs Good W S W S B S _Short shrubs_ (Nesting sites, food, cover near ground) Fragrant sumac Excellent * W SW W SW B SW American plum Excellent ** S SW S SW S SW Common chokecherry Excellent ** _S_ SW _S_ SW SB SW Chickasaw plum Excellent * S SW S SW S SW Sargent crabapple Excellent * W S W S WB S Cotoneaster Good S S S S S S Amur maple Excellent * S S S S B S Coralberry & snowberries Good - Excel W SW W SW B SW ^1 Bold letters or two dots indicate an especially good wildlife feature. ^2 Several plants in this list have a variety of species or cultivars, and some may have features that differ from those indicated. Also, there may be good plant selections for your area that are not included. Planting Designs With Wildlife in Mind Windbreaks are planted to protect farmsteads, livestock, roads, or crops. The additional goal of providing wildlife benefits can be added without compromising the primary purpose. In developing a plan, select a design, plant materials, and location that meet your specific windbreak needs but include factors that benefIt wildlife. Below are some designs with tips on improving them for wildlife. Overall Guidelines Choose trees and shrubs that have wildlife benefits, but that are adapted to the local climate, Generally, native species are the best bet because they are adapted and familiar to wildlife (Table II). Include a variety of trees and shrubs in the windbreak planting. This gives a more natural landscape appearance, improves wildlife values for more species, and reduces the chances of disease or insect pest problems. Where appropriate, select a site that connects to a larger habitat block such as a river corridor, woodlot, wetland, woody draw, or similar area. Consider planting a wildlife food plot or leaving grain fields unplowed. The cover reduces soil erosion and, on the lee side of windbreaks, wildlife have a food source in a sheltered spot. Consider planting or leaving herbaceous vegetation such as a mixture of grasses and legumes, grain, or stubble as a border, 20-50 feet wide, along the edges of windbreaks, but avoid competition with new plantings by keeping a clear area next to the trees. This provides nesting, loafing, and foraging cover for pheasants, quail, meadowlarks, and others. On the windward side, such cover also improves wind protection and shields newly planted trees from desiccation and abrasion caused by blowing soil. Mowing, if needed, should be late in the season to avoid nesting wildlife (e.g. August) and limited to every 3-4 years to maintain standing cover for early nesters. Consider adding a row of shrubs to the windward side to trap snow before it gets to the main windbreak and to improve wind protection near the ground. _Field Windbreaks._ These windbreaks are often planted across productive cropland to reduce wind erosion, distribute snow, conserve soil moisture, and increase net crop yields. They can provide benefits as travel lanes and as feeding, loafing, and/or nesting sites for birds such as pheasants, quail, mourning doves, and songbirds. To enhance the value of field windbreaks for wildlife: Choose a variety of trees adapted to the site and that have wildlife benefits, and plant them so there is a mix of tree types within and among rows. Alternate trees and shrubs within the row, or consider adding a shrub row immediately next to the tree row on the leeward side. Stagger the tree and shrub rows to better fill gaps. Shrubs will provide critical ground cover and add foraging and nesting sites near the ground. Where possible, add a row of shrubs around the field edges to connect the windbreak rows. These provide safe travel lanes plus additional foraging and nesting sites. _Farmstead and Livestock Windbreaks._ Windbreaks with four or five rows are commonly used to protect farmsteads or livestock. Greater width may be necessary for wildlife protection in winter in northern climates. For example, eight-row windbreaks have been recommended for wildlife protection in Minnesota, and more than eight rows may be needed to provide ample winter protection in Manitoba and North Dakota. 1771-5a.gif overview of windbreak 1771-5.gif _Windbreaks can be given a more naturalistic look and still provide excellent wildlife habitat and wind protection._ Source: Minnesota Department of Natural Resources. In contrast, one- to three-row windbreaks are commonly used farther south in areas such as the Texas panhandle. In general, greater width provides better winter protection. An ample ground cover layer, availability of food resources, and connections with larger blocks of protective cover are also critical factors in winter survival for pheasants, quail, and other wildlife. If an established windbreak fills with snow or otherwise does not offer adequate winter habitat, consider adding the needed plantings to improve it. Below are some design tips for a five-row windbreak. On the windward side, often the north or west side, use two rows of evergreen trees such as eastern redcedar, Rocky Mountain juniper, or other native conifer species. Spruce and fir are recommended for more northern sites. Stagger the trees in the two rows so that all spaces are better occupied. For the middle row (or middle two rows), use tall deciduous trees such as those in Table II. A variety of deciduous trees mixed through these rows provides more benefits to more wildlife species. Add a row of tall shrubs and a row of short shrubs on the leeward side. Planting a variety of shrub species with high wildlife values is the best approach (examples in Table II). _How big should a windbreak be?_ Larger windbreaks benefIt more wildlife than do smaller ones, and some birds need a certain minimum size windbreak before they will use it. For example, insect-eaters such as brown thrashers, black-capped chickadees, least flycatchers, gray catbirds, and yellow warblers have size requirements for nesting territories--several rows in width and at least 1-3 acres. For mammals, little information is available on specifIc size needs in relation to territory or behavior, but they may not be quite as critical. Where wildlife winter shelter is a specific purpose of a windbreak, the size needed, especially width, will be greater than for other purposes. For example, shelterbelts in northern-most states may need as many as 20 rows of woody plants or be up to 300 feet wide and have adequate ground cover to ensure pheasant protection. Less width will suffIce in the mid to southern states. Several windbreaks that are close together or are connected to larger habitat areas become larger overall and may meet minimum size needs. Older Windbreaks As a windbreak grows, it will gradually become more complex in structure, with a well-developed understory and a variety of types and shapes of plants. Most wildlife will accept windbreaks after they are at least five years old; those over 40 years old are more likely to be accepted by hawks, owls, and cavity nesting birds. Throughout the life of a windbreak, maintaining good wind protection and cover near the ground are important characteristics for variety and abundance of wildlife, especially for pheasants, quail, and many songbirds. 1771-6a.jpg photo: small rabbit 1771-6.jpg _Windbreaks provide habitat for game animals such as rabbits, quail and pheasants._ Photo: Ron J. Johnson. _Wildlife Helpers._ With established windbreaks, consider adding rows of shrubs to benefIt wildlife along the leeward edge or planting additional conifers or shrubs along the windward side. Other options include adding an adjacent herbaceous strip to provide nesting cover and additional shelter near the ground, or adding length to connect the windbreak to existing woodlots, river corridors, wetlands, or similar places used by wildlife. _Snags._ Snags are trees that have died and possibly lost limbs or tops but are still standing. Snags are great for wildlife. If they're not where they pose a safety hazard and there is no other reason to remove them, consider saving them for wildlife; owls, woodpeckers, and chickadees use them as nesting and foraging sites. Another option is to top the snag, leaving a stump about 15 feet high to provide wildlife benefits yet allow sunlight through to other trees and understory plants. _Nest Boxes._ Adding nest boxes to younger windbreaks will bring cavity nesters sooner and also will help in more mature windbreaks. Nest boxes attract and provide nesting sites for many desirable cavity nesters such as chickadees, woodpeckers, house wrens, American kestrels (sparrow hawks), and bluebirds. Be a Windbreak Detective There is much we need to learn about wildlife in windbreaks and about how people interact with wildlife in relation to windbreaks. Your observations or notes of what you've seen and done may become important to you and to others interested in windbreaks. Here's a challenge: write yourself a windbreak wildlife notebook. You might note when the windbreak was established, what wildlife are seen in or near the windbreak, what they were doing, how wildlife use changes over the years, and how you and your family use the windbreak. If you can't see the wildlife, such as nighttime animals, look for tracks and possibly make plaster of Paris casts. Or listen for the many bird, insect, and other sounds in the windbreak. If you have a food plot, waste grain in a crop field, or other food source next to the windbreak, jot down what wildlife use it. You might also note what you think about wildlife in the windbreak. For example, are there obstacles or concerns that need new solutions? Are there fun, educational, or family experiences that others interested in windbreaks should be aware of? Use your wildlife windbreak notebook ideas for fair displays, speeches, or show-and-tell; and write the authors so we can improve future windbreak information. EC1771 mailto:pubs@unl.edu?subject=Comments from EC1771 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. http://www.ianr.unl.edu/pubs/forestry/ec1772.htm Windbreaks in Sustainable Agricultural Systems, EC 94-1772-X This publication discusses how well-designed windbreaks benefit feedlots, livestock pastures, and calving areas." University of Nebraska Cooperative Extension, EC 94-1772-X By Vernon Quam and John Gardner, North Dakota State University James R Brandle and Teresa K. Boes, University of Nebraska 1772-1a.jpg photo: sunflower field and windbreak 1772-1.jpg Sustainable agriculture is a system of whole-farm resource use balanced with whole-farm productivity. The overall level of productivity achieved is dependent upon the ability to coordinate and manage simultaneously the soil, water, plant, and animal resources within climatic and economic limits. Both the kind and amount of plants and animals supported by the system are important and play significant roles, both individually and collectively in maintaining a healthy farm environment. In the future, integrated systems will help reduce human impact on resources while providing sufficient supplies of high quality food and fiber. _Field windbreaks increase yields in sunflowers and other crops, resulting in net gains in productivity and increased economic returns. For additional details see EC91-1765._ Photo: J. Brandle Windbreaks provide protection for people, animals, buildings, crops, and natural resources. They reduce soil erosion by wind and contribute to the control of runoff from agricultural lands. Individually, trees and shrubs can provide food and shelter for wildlife or be harvested for timber and fuelwood. Specialized tree crops, such as fruits or nuts can be harvested from windbreaks providing additional economic returns. Windbreaks in Agriculture Trees and shrubs have an important role to play in today's integrated agricultural systems. Riparian forests provide valuable wildlife habitat and timber, erosion protection for stream and river banks, and act as filter strips for agricultural runoff, protecting water quality and fish habitat. Trees and shrubs planted as windbreaks provide wind erosion control, improve crop yield, and enhance the quality of many wind-sensitive crops. Farmstead windbreaks protect the home site and reduce energy consumption. Windbreaks can reduce stress on livestock, improve weight gain, and reduce mortality of young animals. Properly designed windbreaks can provide additional income from wood products, tree crops, and fuelwood while enhancing wildlife populations. Finally, windbreaks add beauty to the landscape and increase the value of the land. Soil and Water Conservation Soil and water conservation in natural ecosystems is aided by the high proportion of perennial plants and their established root systems. In agriculture, crops and their soil stabilizing roots are often removed annually, leaving little to protect the soil from rain and wind. Properly spaced and managed trees, shrubs, and/or grass strips interspersed among fields of annual crops help provide many of the same benefits as complete perennial cover. Roots and shoots remain year-round, holding steep slopes in place. Soils susceptible to wind erosion are protected by a reduction in wind speed. In addition, windbreaks aid in the deposition of wind-borne soil and snow, building fertility and storing moisture. When combined with conservation tillage practices, significant soil benefits can be achieved. In milder regions with continuous crop production, windbreaks provide year long soil and crop protection. Fine soil particles move easily in the wind. These soil particles contain most of the humus and nutrients in the soil, and if lost, soil fertility is reduced. Normally, soil particles do not move until the wind velocity is about 13 miles per hour, one foot above the ground. Windbreaks help protect cropland by reducing wind velocities for a distance approximately 15 times the height of the tallest trees (15H) and thus provide significant reductions in the rate of soil loss over large areas. In areas where snow provides a critical source of soil moisture, windbreaks increase the probability of successful crop production by capturing and distributing the snow across fields. Where snow is not a major source of soil moisture, windbreaks still provide valuable winter protection to fall planted crops by reducing soil erosion and decreasing plant abrasion and desiccation. With proper design and management, windbreaks can provide benefits to soil and water resources in most agricultural regions. Field Windbreaks Windbreaks reduce wind speed and change the field environment. Depending on the crop, the type of soil, and the local climate, various benefits to crop growth and development occur. In some areas, winter protection and snow cover are critical to winter wheat production. Uniform snow distribution contributes to added soil moisture for spring crops. Temperature and humidity changes may lower evaporation and increase crop water use efficiency and photosynthesis. Reduced wind speeds lower evaporation rates, improve irrigation efficiency and reduce pumping costs. 1772-2a.jpg photo: native shrubs and fencerows 1772-2.jpg _In many areas fencerows have grown up with native trees and shrubs. Instead of removing these trees they can be managed to provide excellent windbreaks._ Photo: D. Berne While a windbreak requires that some land be removed from crop production, it results in a net increase in total crop yield and crop quality. Overall the net economic return is positive, input costs are reduced, and environmental conditions are improved. Another important benefit of field windbreaks is the opportunity for a greater diversity in crop choices. Greater crop diversity has the potential to increase natural control of pest outbreaks and hence contribute to the ecological stability and resilience of the farm ecosystem. The presence of a windbreak contributes to greater habitat diversity, providing homes for a wider range of microbes, insects, plants and wildlife. With careful planning and management, field windbreaks improve economic return by enhancing insect predators and reducing the need for pesticides. Livestock Windbreaks Livestock have a dual role in sustainable agricultural systems; they convert grass, grain, crop residues, and otherwise non-economic by-products, into high quality commodities such as meat, milk, eggs and wool; and they provide a valuable means of cycling nitrogen, reducing the demand for external inputs. Their production on an integrated farm operation is increased by windbreaks designed to protect feedlots, pasture, or range. Livestock windbreaks are generally designed to provide protection during the late fall, winter, and early spring. By reducing wind speed, animals can be protected from the dangers of wind chill. Livestock in protected areas experience less cold temperature stress, improved health, increased feeding efficiency and improved reproductive success. Windbreaks are especially valuable during the calving season, when protection from late winter and early spring storms is most critical. In dry, northern rangelands windbreaks can be designed to trap snow, providing water for livestock. Whenever livestock have access to windbreaks, fences should be built to eliminate destructive grazing. Without protective fencing, livestock will destroy the effectiveness of your windbreak. Farmstead Windbreaks Protection of farm or ranch buildings is a sure way to reduce the energy costs associated with heating and cooling these structures. During winter months, dense, multi-row windbreaks reduce the effects of cold winter winds and provide energy savings of 10 to 40 percent. Windbreaks reduce wind chill effects on humans, making outside work during winter less stressful, more efficient and safer. Properly located windbreaks reduce snow drifts in driveways and work areas, save fuel and add to the value of the farmstead. During the summer, in areas of hot, dry winds windbreaks can directly reduce the costs of air-conditioning your home. Shading the outdoor compressor of your air-conditioner can also result in savings on summer cooling bills. Properly located tree and shrub plantings provide summer shade for the home and reduce heat load on the building. The shade from a large multiple row windbreak can provide a cool outdoor family recreation area. Windbreaks not only conserve energy, but also produce energy in the form of fuelwood--an inexpensive and renewable source of energy. In addition to home heating, fuelwood may be used as fuel for biomass burners providing an alternative to propane for drying grain or other on-farm operations. Large commercial heating systems using wood chips as a fuel are becoming more common and may provide a potential market for excess wood. well-designed farmstead w/windbreaks 1772-3a.gif _An example of a 160 acre farm designed to take full advantage of windbreaks and other woody plantings. With a little imagination and careful planning, landowners can enhance both wildlife benefits and economic returns from their land._ Source: Minnesota Department of Natural Resources. AgroforestryWindbreaks can be designed and managed to provide an assortment of wood products while continuing to provide their primary benefit- -wind protection. These types of windbreaks generally require intensive management and special care must be given to maintain the overall structure of your windbreak since it is this structure that reduces wind speed. 1772-4a.jpg stand of pecans 1772-4.jpg _Several species such as black walnut or pecan (as shown here) offer excellent nut and timber opportunities to the integrated farm operation._ Photo: J. Bratton. The management of existing multiple row windbreaks (10 rows or more) for timber or fuelwood is similar to that of a small woodlot. Larger trees, such as poplar and ash can provide lumber for crates and pallets. Cedar and juniper are resistant to decay and can provide posts and poles. Cedar may also be chipped for animal bedding and brings a premium when packaged for the small animal or pet market. Other types of wood chips have been used for livestock bedding, landscape and garden mulches, and fuel. In areas near large urban markets, firewood can provide additional income. For those with a long term outlook, new windbreaks can also be designed to produce timber crops. Trying to anticipate the future wood market is difficult and care should be taken when selecting species. High quality hardwoods such as walnut, oak, and possibly ash offer the best opportunities. While not for everyone, Christmas tree or nursery stock production can be a part of a windbreak system. These crops are very specialized and labor intensive. They require specialized equipment, intensive business skills and a good understanding of marketing; however, by a series of plantings and harvests, both protection and tree crops can be realized from an intensively managed windbreak system. The planting of fruit or nut trees and shrubs in your windbreak is one way to integrate their wind-blocking function with the production of food. The harvesting of fruits for personal use or for sale helps add to the value of the windbreak land. Fresh or dried fruits and nuts, jams, juices, and wine are some of the possible products available from windbreaks. Brambles such as raspberries and blackberries, may also be planted in the outer rows of some types of windbreaks providing fruit for market or home use. Remember that brambles spread aggressively and require a higher degree of maintenance than other species. High-quality fruit and nut crops require intensive management and generally include irrigation systems and high levels of pest control. Less intensive management results in lower quality and inconsistent crop size, but provides products which are suitable for home use, local farmer markets, or pick-your- own operations. Wildlife in the windbreak may be considered a detriment to the production of fruit or nut crops. However, wildlife are harvestable, and can become a part of your integrated agricultural system. Windbreaks offer good wildlife habitat and may provide additional income from fee hunting or other recreational activities, especially near urban centers. The integration of agroforestry practices into sustainable agricultural systems can provide many rewards. It requires, however, careful consideration of all aspects of your operation, an understanding of basic ecological principles and a working knowledge of local conditions and markets. For help in adapting agroforestry to your farm or ranch contact your local forester, district conservationist or extension agent. Your goal should be to take advantage of practices which enhance the environment and provide added profitability to your operation. EC1772 mailto:pubs@unl.edu?subject=Comments from EC1772 Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Elbert C. Dickey, Interim Dean and Director of Cooperative Extension, University of Nebraska, Institute of Agriculture and Natural Resources. http://www.ianr.unl.edu/pubs/forestry/g1304.htm Windbreak Design, G96-1304-A This NebGuide provides general information for designing a tree and shrub windbreak. Landowners should work with a natural resource professional to develop site-specific tree planting plans." _G96-1304-A_ Jon S. Wilson--District and Extension Forester What is the best design for a windbreak? The answer depends on the objectives of the windbreak and the characteristics of the site where the windbreak will be located. The optimum windbreak will include enough trees to provide both wind and snow protection. windbreak profile windb1.gif _Figure 1. Typical windbreak profile_