This is the nymph (juvenile) of the Spotted Lanternfly. Before this stage, they are black with white spots, and after this stage, they will be mature adults that have wings and are predominantly a black and pale gray color. This invasive insect is found across Maryland at this point (and in several other states), so managing them is not necessary or practical, as control efforts will not eradicate a local population. Lanternflies suck plant sap, like aphids and leafhoppers, but generally do not cause home landscape plants any damage. (They might cause crop problems for vineyards, but even then, such farms using insecticides tend to get them under control fairly easily.) You can report your sighting to the MDA if you wish (the link to the reporting form is in the page above), but they are already aware of the insect's presence in nearly all Maryland counties.

Lanternflies cannot bite or sting (their strong jump may startle someone, but they can't hurt us), though a pet eating enough of them (as with any insect, like abundant cicadas) might get a stomach ache from their hard-to-digest exoskeletons. Depending on what the lanternflies have been eating, they also may taste bad if a pet or child tries to eat them. (If the lanternfly has been feeding on their favorite invasive tree, Tree of Heaven, they will pick up chemicals from that host that make them distasteful, which is why they evolved to have those warning black/white/red colors for predators.)

Miri