What kind of trees are these

Asked July 8, 2020, 9:13 AM EDT

Can you please tell me what kind of trees these are?

Harford County Maryland

1 Response

The first and third photo could be native Black Walnut; native Sumac and invasive Ailanthus look very similar. If you can reach any foliage, rub the petiole (leaf stem) and sniff - while scents are certainly subjective, they do smell different. Walnut is pungent and smells earthy and nutty (or citrusy or spicy, depending on who you ask). Ailanthus is pungent but smells like burnt peanut butter and is usually considered unpleasant. Sumac doesn't have a notable odor or will simply have a mild, generic "green" or "leafy" smell. Walnut also often has no terminal leaflet, meaning that the last single leaflet at the end of the compound leaf is missing; this photo appears to show that trait.

This illustrates some differences as well on page 10:
and at the bottom of this page:

The center photo appears to be Japanese Stiltgrass, a highly invasive weed. More information is available here: https://extension.umd.edu/hgic/topics/japanese-stiltgrass