Box Elder Bug Life Cycle
- As winter weather warms, adult boxelder bugs feed on leaves and seeds of female boxelder trees at ground level. If unavailable, the bugs will feed on maple or ash leaves instead of boxelder. Within a few weeks of emerging from hibernation, boxelders move from ground level up into the branches of trees to mate and lay eggs. Western boxelder bugs, also known as Boisea rubrolineata, will lay eggs in the crevices of boxelder bark. Eggs typically hatch in a few days, but can take up to 19 days.
- The eggs of a boxelder are typically brown or yellowish in color, depending on the exact species. As a nymph develops within an egg, the egg will gradually take on a bright red color. Various boxelder species require anywhere from a few days to more than two weeks for eggs to hatch. When hatched, boxelder nymphs are bright red, with none of the typical black as seen in adults. Nymphs typically feed on nearby leaves. As they hatch, it is not uncommon to find nymphs on the ground near boxelder, maple or ash trees, feeding on fallen leaves and seeds.
- Nymphs hatch in two cycles during the summer months. Once early in the season, known as first generation, then again in August or September, known as second generation. A nymph grows through six progressively larger stages before becoming an adult. At the initial stage, nymphs are bright red and wingless. Gradually, as it progresses through the nymphal stages, its body size increases, its body turns black with telltale red markings, and wings develop. By the end of summer, first generation nymphs have lived out an entire life cycle. Second generation nymphs that progress through all six nymphal stages before cold weather sets in will hiberate through the winter.
- In mild climates, on winter days when temperatures rise, some boxelders will emerge from hibernation to seek out food and water. When temperatures again drop, the adults retreat back into hibernation. In some climates where winter months are exceptionally warm, entire populations of boxelders may begin to infest homes, garages and other structures. Warm weather brings on activity, but subsequent cold spells may encourage the bugs to seek deeper shelter inside a structure, resulting in unseasonable infestations. Since the bugs are harmless to people, pets and most houseplants, infestations are simply a nuisance and require little in the way of pesticides to eradicate a population.
