These are Spotted Lanternfly nymphs. They are widespread in Maryland, and while high populations can look alarming, they do not cause serious plant damage (or even detectable damage in many cases). The only crop plant at possible risk to harvest reduction or quality is grape, and even then, mainly for vineyards and not home gardeners. No intervention is needed, and we do not recommend using an insecticide (even a low-toxicity organic option) to treat them. You can learn more about this insect on the page linked above.

Miri