"They cleaned out the whole row overnight," my neighbor said over the fence. I checked the row. The deer had stripped the young aspen suckers bare in his Colorado Front Range backyard. The animals that eat aspen are led by four big feeders: elk, deer, moose, and beaver. Elk and deer nip off the tender shoots and leaves. Moose strip the same growth in colder country, and beaver chew the soft bark and cut whole stems. The broader mix of aspen wildlife runs deeper than that, but these four do the most damage you can see.
Aspen pulls in so many mouths because the tree feeds animals better than most others nearby. The leaves are sugar-rich and full of nutrients, which makes the leaves a dietary staple for elk, moose, deer, and beaver through much of the year. The bark stays soft and easy to gnaw, so beaver strip the trunk in long pieces and haul cut stems off to store for winter. Foresters in the Inland Northwest call aspen one of the most important wildlife trees around. If you own even a small stand, you feed dozens of species across one season.
That heavy feeding comes at a real cost to the tree. Aspen browsing can get intense enough to stop a stand from coming back, since animals eat the young suckers faster than the shoots can grow. In Yellowstone and Grand Teton study plots, 100% of aspen seedlings were browsed. The nearby lodgepole pine went untouched. That finding comes from USDA Forest Service and USFWS research. When every new shoot gets eaten, no young tree reaches a safe height. Over time your whole stand ages out without replacing itself, and you end up with only old trunks.
Elk, Deer, and Moose
- What they eat: Tender shoots, fresh suckers, and leaves, with browsing heaviest on the young growth close to the ground.
- When it peaks: Spring and fall, when the suckers are soft and the leaves hold the most sugar and protein.
- The effect: Repeated feeding keeps new sprouts short and can hold a stand back for many years.
Beaver
- What they eat: The soft bark in strips, plus whole cut stems they haul off to store as winter food.
- Why aspen: The wood is easy to fell and the bark packs steady calories through the cold months.
- The effect: One colony can clear the aspen along a stream bank in a single season.
Grouse, Birds, and Small Animals
- Ruffed grouse: Feed on aspen buds and catkins, one of their main winter foods in northern stands.
- Cavity nesters: Flickers and sapsuckers carve nest holes in the soft wood of the older trunks.
- Others: Snowshoe hare, black bear, and many smaller animals both shelter and feed in the same stands.
If you grow aspen in deer or elk country, protect your young trees until the trunks are well established. Put up a fence at least 6 feet tall, since deer clear a lower barrier with ease. Wrap each trunk in a sturdy tree guard or wire cage to stop beaver and the bucks that rub their antlers in fall. Give your young aspen a few seasons to grow past browse height. Once your trees clear that mark, the animals do far less lasting harm.
I lost two of my own aspen saplings to hungry deer before I caged the rest. So walk the base of your aspens through spring and look for chewed suckers and pale, stripped bark. Those are the first signs that browsers have found your stand. Guard the young growth early and your trees stand a real chance of reaching full height. Wild aspen shrugs off this pressure in the forest because the root system suckers fast and wide across acres. A backyard row of three or four trees cannot spread like that, so your plants need real help to make it.
Read the full article: Aspen Tree: Facts, Care, and the Pando Giant
