Boxelder Bug nymph

Commonly found on boxelder trees (Acer negundo), as well as maple and ash trees; they often seek shelter in houses during fall.

They feed on the seeds and developing leaves of boxelder trees, occasionally branching out to other Acer species or fruit trees.

Nymphs go through five instars and are known for their bright red color, which darkens as they mature. They tend to congregate in large groups on warm surfaces.

Generally harmless to humans and do not cause significant damage to most trees; however, they can become a nuisance when they enter homes in large numbers to overwinter.