Box Elder Bugs Life Cycle

life cycle chart

Life Cycle Stages

Box elder bugs are hemimetabolis insects, which means they develop through three stages:

  1. Egg
  2. Nymph
  3. Adult

Eggs

Adult box elder bugs lay their eggs in the spring inside of host trees or on their leaves. The eggs are oval-shaped and rust-red or red-brown. This coloration allows them to blend in with their host trees, thus protecting them from predators.

Nymphs

Nymphs emerge 10 to 14 days after the eggs are laid. They look like wingless clones of the adults. During summer, these nymphs go through a series of molts, develop into adults, and become able to reproduce.

Adults

Overwintering
During the winter months, box elder bugs seek protection from the cold by overwintering. They can fly as far as two miles to find a suitable overwintering site.

The pests migrate toward homes for warmth and hibernation. They gain entry through cracks in foundations, doors, and windows.

Box elder bugs remain hidden throughout winter, but they may emerge if heat sources within a structure are sufficient. Although nymphs may be present in the fall, only fully-grown adults survive cold winters.

The bugs emerge from hibernation in early spring. This is around the time buds on box elder trees begin opening. The pests fly to host trees where they remain active through the growing season.

Encounters & Concerns

Box elder bugs extract liquids from their host trees, but typically cause only minimal damage. These insects will feed on maple or ash trees, as well as box elder trees.