Hornets typically build their nests in tree tops, house eaves or attic rafters but may build them in other covered areas. Hornets build their nests from a paper substance made of saliva and wood pulp.
Queen hornets begin building the nests to protect their eggs. Each cell contains one egg, and she builds outward, creating a comb. The larvae become sterile female hornets who continue building the nest while the queen lays more eggs.
Hornets build their nests proportionate to colony size, with some reaching the size of basketballs. Worker hornets die in the winter, while the queen hides. Hornets only use nests once, and the queen establishes a new nest in the spring.