What good is a dead tree? It can’t grow. It can’t produce oxygen. It can’t provide shade from leaves. It doesn’t look as good as a nice, healthy tree.
So, what good is a dead tree? Dead trees are an important part of our environment. Dead trees support a large community of organisms in several different ways.
Dead trees are home for more than 85 types of birds, mammals, reptiles and amphibians in Illinois. They include the Virginia opossum (Didelphis virginiana), red-headed woodpecker (Melanerpes erythrocephalus), southern flying squirrel (Glaucomys volans), American kestrel (Falco sparverius), broad-headed skink (Plestiodon laticeps), white-footed mouse (Peromyscus leucopus), little brown bat (Myotis lucifugus), gray treefrog (Hyla versicolor), eastern fox squirrel (Sciurus niger) and midland ratsnake (Pantherophis spiloides).
Insects, slugs, spiders, worms, fungi, bacteria and other small organisms use dead trees. Some of them eat the wood. Some of them eat other organisms in, on or near the wood. Some of them use the dead tree for shelter.
Some animals, like woodpeckers, make a cavity in a dead tree to place their nest.
Other animals, like tree squirrels (Sciurus spp.), raccoons (Procyon lotor), mice and eastern bluebirds (Sialia sialis), may use this same cavity at a later time or a natural, hollowed section of a tree as a place to raise their young and/or take shelter.
Little brown bats and Indiana bats (Myotis sodalis) are among the bat species in Illinois that raise their young under the bark of a dead tree.
Insect larvae often live in a standing dead tree as well as after it falls to the ground. Woodpeckers feed on the insect larvae.
Native bees can nest in dead trees. They may use tunnels that were made by beetles. Mason bees (Osmia spp.) and carpenter bees (Xylocopa spp. and Ceratina spp.) are examples of wood-nesting bees.
Fungi, bacteria and mosses live on or in dead trees. They obtain food while helping to decompose the dead tree, returning its nutrients to the soil to be used again.
Salamanders and worms can live in decaying dead trees on the ground. Some snake species lay their eggs in the decaying wood of a dead tree’s trunk. The heat generated by the process of decomposition helps to keep the eggs warm.
Dead trees can be perches for hawks and owls to hunt from. They provide a clear view from which to spot their prey and have no leaves to hinder these birds’ flight.
Fallen branches from dead trees provide cover for eastern cottontails (Sylvilagus floridanus) and other small animals to hide in.
Branches or other debris from a dead tree that fall into a pond, lake, river or similar water body offer protection for fishes and other aquatic animals. Evergreens that are cut and used as Christmas trees in people’s homes are often placed in ponds and lakes after the holidays to provide habitat for aquatic organisms.
Dead trees that partially fall into a water body can be a basking location for aquatic turtles and other reptiles.
Dead trees are valuable wildlife habitat, both standing and when they fall. Try to save a few dead trees for wildlife, if safety is not an issue.