Controlling and Using Snow

We're finally getting some decent moisture. Of course, it's the cold, fluffy stuff but moisture none the less. I hope you had planned for snow before winter as now may be too late to drive posts for a fence. Snow can be a valuable resource if we control it so we can use the moisture where we need it. We can't control snowfall but we can affect where it lands. At least to some degree. That's where windbreaks and snow fences come into play. They can be used to direct the snow into particular locations and cause it to drop where near we want it. In the same manner, they can be used to limit snow in certain areas.

With the drought this year people who used snow fences had it better than those who didn't. We had a couple of pretty good snowfalls this season so those with windbreaks and snow fences were able to have the snow drop where it was needed most. For myself that was on my trees and garden. I had planned to set up snow fences in the pasture but never got around to it so I didn't get the benefit of the snow there. Unfortunately, I was going to move the fencing in the lavender field so those plants didn't get crushed again but I was too late. They're covered in about two feet of snow. The garden has about a foot of cover so maybe it'll have good moisture going into the growing season.

In this part of the country windbreaks and snow fences are a way of life, a requirement for living out of town. What's the difference, you may ask? Just the size, really. Other than that, not much. Often a snow fence is short, maybe four feet high, but not always. Just take a look at those huge snow fences that Centennial Lumber erects along the highways. Some of them are ten feet high or more. Then there are the "living" snow fences like the Conservation District plants. Often they're a combination of trees and shrubs. They actually can be more described as a windbreak since there are multiple rows planted parallel to each other. Both serve the same purpose. They hold snow either off of an area or on an area. Both break the wind to slow down the windspeed, either to protect livestock or property. And, for the most part, neither are natural. They're installed or planted.

Since they serve pretty much the same purpose I'll talk about them as if they are identical and will use the terms interchangeably. Windbreaks are often installed to either prevent snow from dropping on a certain spot or, in my case, to hold it on a particular area. Mathematically, a windbreak can be expected to hold snow for a distance about four times its height. For example, a four foot wind break (snow fence) can be expected to slow the wind down enough to drop its snow for about sixteen feet. That is just a general rule of thumb though and isn't written in stone. One of the driveways I clear has a four-foot snow fence, but the snow has been nearly four feet deep for about forty feet out from the fence with high wind. Further down, the neighbors have three rows of trees about thirty feet tall. They hold the snow pretty much off the house, dumping it on the far east side. They're close. Wind speed and the amount of snow has a lot to do with where the snow will fall.

The numbers come in handy in your decision of where to place a new windbreak. If you want to keep snow from piling up in a certain area, I'd suggest keeping it at least 40 feet from the spot you want to keep clear, regardless of the math. A windbreak will slow the windspeed and allow the snow to drop out earlier than it would naturally. Keeping the windbreak 40 feet behind the area you want to keep clear will allow the snow to fall before that area and there will be less snow to fall on the desired location. If you put the windbreak too close, you cause the snow to fall out on top of the area you want clear. Although, if there's a lot of snow over a long period it will continue to build up unless you keep it cleared. It can end up dumping the snow in the exact spot where you don't want it.

Distance plays a major role when considering a windbreak and so does height. When planting trees be sure to consider the mature height of the trees. If a tree is going to be 40 feet tall at maturity, the math says it will affect the wind pattern for about 160 feet. It will drop snow within that 160 feet but will slow the wind for the full distance. Of course, this a diminishing effect. The farther away from the windbreak, the less protection from the wind and the less snow will be held. Hence, the slope on the snow as it moves away from the windbreak. If you are planning a windbreak with trees, add some taller, maybe fast-growing, shrubs to affect the wind pattern while the trees mature. Planting the shrubs on the windward side (the side the wind is coming from) will help protect the trees until they mature and add moisture to the soil. The most common placement for windbreaks is along an arc from northeast to southwest of the area you want to protect. It doesn't have to be an arc. Your windbreak can be straight lines, but that arc will take care of most of our winds.

Windbreaks are intended to be used for our benefit but can quickly become a detriment if they are installed without preplanning. It's easy to draw a diagram of your property (preferably to scale) and show the prevailing winds. Then take a paper cutout of your planned structure and you can move it around on the paper to see how it will affect the wind in various locations. Trees and shrubs can work the same way. A little bit of planning and you can save yourself major headaches later on. A good source for windbreak planning is the Laramie County Conservation District. They only work with trees and shrubs, but they will go over your property and design a windbreak that will work well for you. You can get low-cost trees and shrubs from them and, for a fee, they can even do your planting. It's worth it.

A good, well-planned windbreak is a great help and can lessen your workload after a storm. But it does have to be planned out and properly placed. If you have any questions, ask a Master Gardener. It's what we do.