Tree Swallows arrive every spring around March 21. They claim their favorite nest box and defend it from other Tree Swallows and Chestnut-backed Chickadees. They use a grass, straw and feather-lined nesting cup. You can see images of their nest and eggs in the Habitat Section.
When the swallows have raised their brood and leave the nest box, we remove the nest and clean the nest box. In the spring, we place a handful of cedar shavings and wood ashes in the nest box in preparation for their arrival. If the Chestnut-backed Chickadees choose that nest box, the chickadees remove nearly all the material, mouthful by mouthful. The swallows, however, seem to enjoy having a base already started in the box and build a nest on top of the shavings and ashes.
Note: Wood ashes deter mites and are an important addition to a Tree Swallow nest box. Use a handful per box.