Knowledgebase
Identifying Tree of Heaven #754908
Asked June 08, 2021, 6:29 PM EDT
Prince George's County Maryland
Expert Response
This appears to be Black Walnut (Juglans nigra), a native tree with good wildlife value, but they can look similar to Tree-of-Heaven (Ailanthus) and the photos are a bit small for us to see clear details to be sure. Here are some pages with information and images that you can use to compare the two:
https://extension.umd.edu/resource/tree-heaven (see additional links at the bottom of the page for good comparisons with similar species)
https://www.marylandbiodiversity.com/view/1625
https://www.marylandbiodiversity.com/view/1412
The "sniff test" will also help, though to some people, both scents are offensive (they just smell different). More universally, people strongly dislike the scent of Ailanthus, when the leaf stem is rubbed or the foliage crushed. Rancid or burnt-smelling peanut butter is a common description. Black Walnut is described as smelling earthy and a bit like...well, walnuts, though it's harder to describe otherwise, especially if one isn't familiar with that scent.
Black Walnuts get a bad reputation for being difficult to garden under due to chemicals they produce, but these claims are largely unproven in scientific studies and often it's other factors that keep plants from thriving underneath them. Ailanthus, on the other hand, is quite invasive and should be removed, of which we imagine you are already aware.
Miri