Windbreaks for Livestock Protection All warm blooded animals must maintain their body temperature within a very narrow range. Livestock are similar to humans, except they can’t throw on a jacket. Windbreaks can help livestock do this by providing an area of protection from the elements.

Windbreaks for the protection of livestock come in many different sizes, shapes, configurations, layout, uses, etc. Feedlot windbreaks protect areas to be used for extensive periods (> 1 month) or a continuous basis for feeding and holding animals Livestock windbreaks or Living Barns protect areas which will be used for livestock on an intermittent or emergency basis Collectively, these windbreaks would be any tree and/or shrub linear planting with the primary purpose of protecting any number of livestock. This is not just large, commercial feedlots with large numbers of animals.

Livestock Protection Livestock Needs Heat Loss Cold Winds Drifting Snow Access to Water and Feed Heat Stress Producer Needs Access to Livestock Cold Wind Feedlot Pasture, crop field or Range Livestock protection relates mostly to the protection from cold, blowing snow and blowing soil particles What are the resource needs associate with livestock that windbreaks can help address? Some are directly related to the livestock and some are more related to the producer as they manage their livestock. Heat stress is included as something to avoid exacerbating. Poorly planned windbreaks can create an area that has no air movement, which in the summer can be a problem.

Percent Increase per Degree of Cold (F) Livestock Response to Cold & Windchill Maintenance Energy Requirements for Cattle Below Critical Temperature Beef Animal Weight (lbs) 440 660 880 1100 1200 1320 Description Critical Temp Percent Increase per Degree of Cold (F) Summer Coat or Wet 59 2.3 2.1 2.0 1.9 Fall Coat 45 1.5 1.4 1.3 Winter Coat 32 1.2 1.1 1.0 Heavy Winter Coat 18 0.7 0.6 We primarily use windbreaks to protect livestock from wind in the late Fall, Winter and early Spring. -Cold animals will need more food energy just to stay warm. Which means less food energy can be turned into weight gain. -Notice that smaller animals have a slightly greater energy requirement to maintain warmth. This is particularly critical with young calves. - Milk production in dairy cows is impacted similarly <35 degrees = lower production Example: An 880 lb animal with its winter coat has a critical temperature of 32 degrees and will require 1.1 % more feed per degree of increased cold. With calm conditions and a temperature drop to 20 degrees, feed consumption is increased by 13%.

Little danger to mature animals Note that this chart is for mature animals. This chart is about assessing danger for the animals, not weight gain or milk productivity. Example: An 880 lb animal with its winter coat has a critical temperature of 32 degrees and will require 1.1 % more feed per degree of increased cold. With a temperature drop to 20 degrees and a windspeed increase to 20 mph, the equivalent temperature decreases to -10 degrees. With a temperature change of -42 degrees, the feed consumption is increased by 46%. Little danger to mature animals Increasing danger: will freeze exposed flesh such as teats and scrotums; will stress animals causing latent diseases to appear Great danger especially to young animals

Example: An 880 lb animal with its winter coat has a critical temperature of 32 degrees and will require 1.1 % more feed per degree of increased cold. With a temperature drop to 20 degrees and a windspeed increase to 20 mph, the equivalent temperature decreases to 0 degrees. With a temperature change of -32 degrees, the feed consumption is increased by 35%. With a windbreak the feed consumption is reduced to an increase of 21% or a savings of 14% in feed costs.

Temporary or Mobile Shelters Available now Where you want them Relatively short length Small area of protection Short lifespan Expensive As has been said earlier the primary benefit of a windbreak is the reduction of wind speed. Consequently any structure that reduces wind speed can be beneficial for livestock. There are numerous companies that sell structural, temporary or mobile windbreaks. As well there are numerous extension pubs and research papers on the value and design of mobile and permanent structures type windbreaks. Not surprising, there are pros and cons for these kinds of windbreaks. -The most significant advantages are their almost instant protection and they can be installed nearly anywhere. -The major disadvantages are the limited area of protection and expense, Related to expense is the relatively short lifespan. One example -- Cost of 60’ Stationary Windbreak......$6,58000

Feedlot/Livestock Windbreaks Design is similar to that used for structures 60-80% density Minimum 3 rows Typically 5 rows – for greater snow storage Windward row – shrub Center – taller trees Density is the primary driver for designing livestock protection windbreaks. Dense windbreaks create the greatest wind speed reduction and create short deep snow drifts. For feedlots these two factors are important. Density is created with some combination of conifers, multiple rows or shrubs.

Feedlot/Livestock Windbreaks Spacing for primary windbreak Between rows – 15-24 ft Create space for snow storage Within rows – Closer spacing helps the windbreak become effective sooner Vary the within row spacing from row to row In areas where cold winds are an issue, snow is also commonly an issue. The design should promote snow storage within and directly adjacent to the windbreak. The goal is to avoid drifting snow into the area of greatest wind reduction. This allows the livestock to take advantage of as much of the protected area as possible.

Feedlot/Livestock Windbreaks At least one row of conifer Fencing should be far enough away to allow for maintenance and reduce snow damage Minimum 100’ wider than either end of the area to be protected. Consider a second leg of the windbreak – “L” shaped Snow trap – shrub 100 ft. on windward side

Design Considerations Drainage Trap snow outside of livestock feeding area Provide channel for snow melt (drainage) away from protected area Minimum of 20 feet of the leeward row for drainage and snow storage Designing for snow melt runoff is very important. Because the windbreak will be collecting snow, there must be space and allowance for snow melt to drain away from the feedlot. Just as important is to make sure that rain and snow melt runoff from the feedlot does not drain into the windbreak. The salt concentrations will easily kill trees and shrubs.

Feedlot/Livestock Windbreaks Location Protected area within 2-5H The area of greatest wind reduction is between 2-5H downwind. Remind the producer to keep water and feed troughs away from areas likely to be drifted over with snow, as well don’t place water at the far end of the lot away from the wind protected area. This will cause the livestock to spend lots of time walking back and forth to water or possibly avoid drinking.

Outdoor Living Barn Livestock can also benefit from wind protection in open pastures, grazing on crop stubble and rangeland.

Outdoor Living Barn Utilize the terrain Use multi-legged windbreak design – use letters E, L, C, F Placement of living barns can take advantage of existing terrain, areas accessible to the producer during difficult weather or to provide a source of protection in wide open country. -Living barns should be designed to be useful under a variety of scenarios. A single-legged linear windbreak provides little protection when the wind is parallel to the windbreak orientation. -Multi-legged windbreaks protect a larger area. -Even though livestock protection fence is expensive, allowing livestock access to all sides of the windbreak can help provide protection regardless of the direction of the wind. -It is necessary to provide enough room for livestock to be out of snow drifts if the area is completely enclosed by windbreaks. Try to locate the access into the protected area where it is least likely to drift shut or allow wind to blow into the protected area.

From NRCS National Website: Land Use/Forestry/ There are many places to go for practice information, design, and installation guidance. This shows a broad overview of livestock windbreaks from the NRCS National website.

Design Considerations Drifted Snow Area of greatest wind reduction also has deepest snow drifts Possible snow trip row windward of the primary windbreak Include a second leg of windbreak – “L” shape Consideration of where and how much snow can be drifted in your part of the country is important. -With a narrow windbreak the area of greatest wind reduction also has deepest snow drifts. Consider adding a snow catch row of shrubs.

Design Considerations Blizzards from an atypical direction Allow livestock to have access on all sides of the windbreak Establish a secondary and less dense windbreak on the other side of the calving or feeding area An area completely enclosed by windbreaks has mostly calm air. This can lead to significant snow accumulation in the winter and very hot areas in the summer. -A secondary windbreak might be part of the solution. This secondary windbreak can be located to protect livestock when storms and winds come from an atypical direction. However, if that area is used throughout the year this secondary windbreak should be less dense. The protection will not be as great, but it will allow some air movement during warmer times of the year. Secondary windbreak

Snow Trap Primary Windbreak Secondary Windbreak This is not to teach you how to make the correct answers. It is designed to show you how to ask the right questions. There are few “wrong” windbreak designs as long as the right questions have been asked and the design addresses the answers to those questions.

The End In summary, properly designed and installed windbreaks provide benefits to feedlots, livestock pastures, and calving areas from reduced wind speed. This lowers animal stress, improves health, and increases feeding efficiency, as well as creates a better environment for the farmer/rancher.