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."
Boreal Owls prefer mixed spruce_hardwood forests, while Saw_whet Owls prefer to nest near the edge of spruce or deciduous forest groves. Woodpecker nest boxes should be placed 6┰ feet above the ground, though Hairy Woodpeckers prefer nest sites 12 feet or more above the ground. Common Flickers nest in open areas and open park_like areas, while Hairy and Downy Woodpeckers prefer open deciduous forests.