Dead trees, or snags, are valuable to a wide variety of wildlife. Unfortunately, many people assume snags are of no value and routinely cut them down. In some places, this practice has caused cavity_nesting bird and mammal populations to decline. Though nest boxes may provide alternate nesting sites for some cavity_nesting birds, they are not suitable replacements for dead trees. Here's why: Snags provide homes for woodpeckers. Woodpeckers use snags for drumming, nesting, roosting, and feeding. Woodpeckers hammer their bills against the resonating surface of dead tree trunks to make a loud drumming sound; this is their courtship and territorial "song."
When to Feed Birds. Some birds will visit feeders year_round once they are familiar with the location of a dependable food supply. Birds are most easily attracted in winter, however, because natural food supplies are least abundant then. Feeders should be set up in late summer or early fall, then maintained through the winter and spring until natural food sources are again abundant.