Tree snags - dead or downed trees in various states of decay - provide vital habitat for as many as 1200 species of wildlife nationwide. Despite the importance of snags to wildlife, many modern forestry practices encourage the removal of dead wood from the forest floor in an attempt to control pests and fungi, as well as for aesthetic reasons. You can create a refuge for hundreds of woodland creatures by keeping snags in your yard (or constructing artificial snags if no natural ones are present).

How does wildlife benefit from snags?
Different species use different parts of the snags. Nearly every part of the dead tree is utilized in every stage of decay. Hollow cavities in standing dead wood make excellent nests for woodpeckers, while insects in the bark provide a ready food source. Other animals use the bark, too, but for a different purpose. Bats, tree frogs and beetles all make their homes in the crevasses between the bark and the trunk. Higher branches become excellent look-outs from which raptors spot potential prey and, later, where they may safely clean and eat their meals.

Invertebrate communities also thrive in decaying trees. Mosses, lichens and fungi all grow on snags and aid in the return of vital nutrients to the soil through the nitrogen cycle. Moreover, they provide an important source of food for a variety of wildlife.

Decaying logs on the forest floor help in another way, too. By acting as "nurse logs" for new seedlings, moisture-rich dead wood can help to ensure that the next generation of forest has a place to grow. These young trees in turn produce additional habitat variety for wildlife.

Below is a chart which shows a just a few of the myriad habitats and uses for tree snags:

How can you help?
By some estimates, the removal of dead material from forests can mean a loss of habitat for up to 1/5 of the animals in the ecosystem. You should never allow dead wood to rest against your home and any trees which may fall on your home should be removed, but in other cases it is safe to allow standing dead trees and downed logs to remain on your property. As long as the snags are a reasonable distance from your home, there is no risk of damage by termites or other pests, and this will be a tremendous help to the wildlife that make their homes in your yard. You will also gain additional benefits in the form of soil runoff prevention as the trees help to hold the soil in place.

If there are no natural snags in your yard, you can create artificial ones by trimming branches on live trees of varying sizes and types. Hardwood trees tend to make better nesting habitats while softer wood is better for food foraging. Learn more about creating snags in your yard.

Three snags per acre is a good estimate for most areas, but you should check with your local wildlife management authority to get specific recommendations for your region.

If you do not wish to create snags from living trees, the use of nesting boxes can be a good alternative. Be sure to use boxes whose construction is appropriate to the type of wildlife you wish to attract. Place the boxes in the most favorable areas for each species, and provide predator guards and other protections as appropriate. The boxes will need to be maintained and cleaned at least once a year so that wildlife can use them effectively. Be sure to do this when the boxes are vacant so as not to disturb any residents!