How to know Tree-of-Heaven, Ailanthus

The compound leaf ends with a leaflet. In walnut, a close look-alike, a tip is seldom present.

Characteristic bark in large trees.
Ringing the growth layer (cambium)
and applying herbicide
is a good way to kill this tree.

A sapling tree. Usually where there is one, there are several.

A line of ailanthus along the Parkway
in section 3.

The leaf scar, seen in winter, is
unusually large and distinctive.
Better than a picture -
the odor of a crushed leaf.
Some say it is like peanut butter.
Neither of two lookalikes,
walnut and sumac, have as
pungent a smell.