These bugs are not a concern for the health of elm trees, but they have become a nuisance pest, similar to boxelder bugs, by entering homes and buildings in the spring, late summer and fall.
Unlike boxelder bugs, these pests can emit a pungent smell, similar to bitter almonds, from their scent glands.
The main problem with elm seed bugs is they can live a long time. In fact, most will live 3-5 years. This means they’ll have to migrate out of bad weather looking for a good place to live for winter. And it appears these migrations will happen in the late summer and fall.