Planning windbreaks for cattle
Kathy Parker, Freelance Contributor – TRI STATE LIVESTOCK NEWS
“Anything a rancher can do to help protect livestock from winter weather is beneficial. Spending money on moveable or permanent windbreaks may be worthwhile, depending on the situation. It may be more cost effective to use windbreaks when buildings are not available for shelter and natural windbreaks are sparse. In addition, windbreaks may be constructed faster than buildings.
Cattle stand cold temperatures without wind pretty well, but according to the University of Idaho’s Jim Church, a 20-mile per hour wind is equivalent to 30 degrees of cold. So if the temperature is 10 degrees with a 20-mile an hour wind, the cattle are feeling 20 below zero.
It takes more feed to generate body heat. In fact, Church said for every 10 degrees decline in temperature below 30 degrees Fahrenheit due to wind chill, a cow’s energy requirement goes up 13 percent. Cold stress increases sickness, which increases vet and medicine costs.
Some producers have made use of materials they already have for the windbreaks.
Kristin Zemp grew up on a Wyoming ranch and now lives on an Ashland, Kansas ranch. She said some producers get creative. “Some places just pile junk cars or tires and stuff up. Looks junky, too. Old cars and farm equipment lined up and used as windbreaks can be death traps, especially if young calves can get into small spaces and hurt themselves, or can’t get back out.
“Sometimes the windbreaks themselves can be death traps, Zemp said. “If a big storm with lots of snow and wind comes, cattle sometimes get drifted in and suffocate under the snow or get trampled by other cattle. It’s a damned if you do, and damned if you don’t kind of thing.”
The standard windbreak is two-sided, fashioned into an L or V shape, without a roof. The point of the windbreak typically points northwest, into the prevailing wind. Often, man-made windbreaks are railroad ties or telephone poles tamped upright into the ground and then either boards or lodge poles are nailed to the uprights and often covered with tin of some kind, Zemp said.
In places where the hay meadows double as feed grounds, the stack yards can be arranged to provide windbreaks. The downside there is stock will eventually find a weak spot in the stack yard fence or deer or elk will make one, causing cattle to get to the hay and make a mess.
Dr. Lindsay Chidester of the Nevada Extension Service said research has shown livestock that have access to windbreaks have better overall feed efficiency and less death loss of young animals.” “Research out of Canada has shown that a windbreak can provide decreases in weight loss by 50 percent. The wind chill factor is greatly decreased.
“If you’re working with NRCS or other agency, they may have more specific requirements (about construction and materials). Other windbreaks are constructed of metal, wood and other substances. It is important to determine costs and labor associated with building it,” Chidester said.
“When determining placement, it should be taken into account that you will want to put the windbreak where winter calving, feeding and pasture will be. Ideally, near enough to a water source they can get water, but not so close cows are losing calves in ditches or are at risk for flooding if that should occur. It should be far enough from a fence or structures that livestock can be fed there too in the event of a major storm.”
Dr. David Ames of Colorado State University (retired) said, “How much effort you want to make in building a windbreak necessitates looking at cost versus benefit. If cattle have the opportunity to go into a draw, compared to standing out on flat ground, the cost is low. But when you start setting posts that will hold a windbreak and putting up lumber, that adds more cost.
“You have to measure how much value there would be,” Ames said.
Ames said advantages of windbreaks in Nebraska feedlots have been documented. It’s more difficult to measure the value in cow-calf operations, but some designs have been shown to lower energy feed costs in winter.
There’s no correct way to build a windbreak and no limit to the materials used.
“You need to spread the cattle out,” Ames said. “Windbreaks should be high, dry, well-drained areas.”
So what are the important features for moveable windbreaks?
The typical windbreak is 10 feet tall. To stand up against the wind, the base must be at least the same width or greater than the height of the upright windbreak. That means a 10-foot tall portable windbreak would need at least a 10-foot-wide base.
Each cow should be provided one foot of fence length.
The windbreaks should not blow over, even in extreme winds.
Windbreaks should be easy to move. The rancher should not have to leave the tractor for a move.
Moving the windbreaks is important to keep areas dry, spread animal waste, reduce hauling distances for feed and hay and allow grazing on areas with no natural windbreaks.
Unlike permanent windbreaks, which are usually sold with the land they are on, portable ones can be moved to a new place. If snow accumulates on a portable windbreak, it can simply be moved, eliminating the need for snow removal. Moving the windbreaks gains the advantages. On the other hand, portable windbreaks are generally more expensive to build than permanent ones.
The Saskatchewan government has done extensive research on portable windbreaks and provides a lot of concrete information on design. The effectiveness of a windbreak is measured in wind reduction. Canadian research shows the best protection comes from windbreaks with a fence porosity of 25 to 30 percent. The protected area will extend eight to 10 times the height of the fence. To get 25 percent porosity, six-inch boards should be spaced two inches apart. To get 33 percent porosity, six-inch boards should be spaced three inches apart. There is no significant difference in protection whether the boards are placed vertically or horizontally, but most units are constructed with vertical walls.
Side lift windbreaks are moved with a front-end loader. They may be lifted and placed end to end for a long fence. Less material is used in the frame because skids are not needed. On the other hand, windbreaks with skids can be moved with many vehicles.
The bottom of any portable windbreak should have a foot of ground clearance at the base to prevent snow build-up. Steel tubing is used on top of the windbreak fence as a place to pick it up with the front-end loader. Some designs are hinged, allowing the shape to be changed to fit the conditions.
Slanted designs require more materials to build, but slanted walls with the railing on the back allow calves to bed underneath. Cows may take advantage of the windbreak while calves are bedded where the wall is closest to the ground.
How do portable windbreaks and permanent windbreaks compare?
Ames said each producer must figure out what will work best in specific pastures with regard to where windbreaks are located and what type to use.
“As long as you can do something that protects animals from wind during cold weather, it will be helpful. Cattle will survive in very cold weather, but they eat a lot more and their efficiency of production drops,” Ames said. “A good windbreak can be a win-win where you improve everything.”