Constructing Brush Piles

Oct 5, 2017

If you own a property with some trees or brush and would like to tinker with wildlife management, take note of today’s episode of Wildlife Matters. The Masked Biologist talks about brush piles for small mammal habitat.

Small mammals rarely get attention from natural resource managers these days. Not intentionally; wildlife biologists are fans of all manner of creatures. However, as staff time is reduced, budgets are flat or cut, and priorities are narrowed to huntable “high visibility” species like deer, bear, and turkey, our rabbits, squirrels, and rodents usually end up taking a back seat. Here in the Northwoods, we sometimes hear that numbers of rabbits or hares are down. Sometimes, as is the case with snowshoe hares, that is because of habitat maturation, a moderation of climate, or both. Other times it can simply be because the place you are looking/hunting doesn’t have the right structure to provide one of their life needs (water, food, shelter, living space). In the case of rabbits and hares, you can consider construction of brush piles to enhance their shelter/living space accommodations. Not only lagomorphs, but smaller rodents as well, which feed all sorts of creatures like hawks, foxes, and coyotes.

I usually tell people that I don’t encourage the construction of brush piles for wildlife. Most people do not have the space or materials necessary to construct a proper brush pile. Just as improperly constructed bird houses can kill fledglings, a poorly constructed brush pile can doom young rabbits and rodents. If they are not properly constructed, they may not be used. Or worse, they can actually harm the animals they mean to benefit, becoming a trap where feeding skunks and owls watch and wait.

The misconception is that any old pile of sticks will work. That is not the case. I would not build anything less than 8 feet wide by 8 feet high. That’s right – 400 to 500 cubic feet. With that much material, you need a starter base, or the bottom will squash flat to the ground. Old stumps or logs of oak, maple, ironwood, or another robust wood are ideal. Some large rocks, cinder blocks, well casing or PVC pipe, or maybe a few sturdy pallets would also do the trick. You need something that will create nice entrance and exit holes, artificial tunnels or imitation hollow logs. Make corner posts, with your base items. Stack some logs or large branches like you are building a log cabin. Put a layer of brush down, large end toward the center. With the next layer, put the large end toward the outside. By alternating in this fashion, you can build stability as you gain height. I tell people you want this pile sturdy enough to hold up a 40 pound bobcat, because bobcats love brush piles. You can start with a narrower base, and add brush around the outside as the height grows. I tried it; it is a clumsy process, with a lot of branch wrestling, but it can be done. It looked pretty good the first year, but it didn’t take long and the pile was surprisingly squat and lifeless. I think with a couple of hours of work a year, though, I could make it into a magnificent specimen of brushy habitat.

You can build two to four of these brush piles per acre, no less than 100 feet apart. If you use some hardwood brush, your pile could make it 15 years before it needs maintenance. Hopefully your base is still holding up, and you can freshen it up by adding brush on top. For best results, build near fence lines, margins of timber harvests, or some other habitat edge. If you are going to do it, now is the time, before the winter snows blanket the forest floor.

Striving to make new things familiar and familiar things new, this is the Masked Biologist coming to you from the heart of Wisconsin’s great Northwoods.