Maryland's Wild Acres
Creating a Wild Backyard - Snags & Logs
Living trees provide wildlife with food and shelter, but what about dead or dying trees? What possible use could they have in your backyard?
Trees are like any living thing. They have infancy, youth, maturity, old age and death. As the tree ages and eventually dies, changes in the bark and wood create habitat for animals suited to each stage in the life and death of the tree. Dead trees are called "snags" and when snags fall to the ground, they are called logs.
Animals find shelter in snags. Cavities, which have formed in the heart of a tree from disease or from the loss of limbs, provide a place to nest for woodpeckers, nuthatches, chickadees, bluebirds, owls, wrens, tree swallows, and many other birds as well as raccoons and squirrels. Snakes use tree cavities to shed their skin. Inside a tree, the snake is well hidden during this very vulnerable time. Woodpeckers can actively excavate a nesting cavity in the softwood of a dead tree. When they move out of their hole, other animals can enlarge the entrance and move in. Bats may also roost in tree cavities. Some bat species prefer to roost under the loose bark of a dead tree. The brown creeper, a small forest bird, will nest under loose bark. Ospreys, some hawks, and the great horned owl will nest on top of very tall snags. Cavities and loose bark can also serve a safe place for butterflies and moths to hibernate or metamorphose.
Snags are also very attractive to insects, which help decompose the various parts of a tree. These insects are food for birds, reptiles and mammals. Animals also eat the fungus which grows on trees. Besides using snags to find food, some animals use cavities and loose bark to store food. With their bare branches, snags are great perches for hawks, eagles, vultures and other carnivorous birds. Mockingbirds will also use a branch as a singing stage.
When a snag falls and becomes a log, a whole new ecosystem is created. Tiny organisms, bacteria and fungi begin to decompose the log and become food for other organisms and insects, which in turn become food for all kinds of animals. For example, pileated woodpeckers have evolved a beak to extract insects and other food from snags and logs.
Holes left in the wood collect water that becomes a place to drink or bathe. The rotting wood, damp from chemical changes, also attracts salamanders and tree frogs. Logs that have fallen in rivers and ponds provide resting places for birds and turtles, and safe havens for fish. Logs also create a nutrient rich soil in which ferns, forest plants, and trees can grow.
Tips for Snags and Logs
Some Areas of Caution
Downed Log Users
|Barred Owl||Black Bear|
|Red Bellied Woodpecker||Otter|
|Carolina Chickadee||Bob White|
|Red Tailed Hawk||Painted Turtle|
|Screech Owl||River Cooter|
|Eastern Bluebird||Box Turtle|
|Tufted Titmouse||Ruffed Grouse|
|Great Crested Flycatcher||Bullfrog|
|Wrens||Eastern Fence Lizard|
|Various Bugs and Insects|
For Additional Information, Contact:
Wildlife and Heritage Service
580 Taylor Ave, E-1
Annapolis, MD 21401
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Write to Me!
Natural Resources Biologist II
Maryland Wildlife and Heritage Service
MD Dept of Natural Resources
580 Taylor Ave., E-1
Annapolis MD 21401