Note the massive spines on the trunk. Smaller spines are on most of the branches as well.
Leaves are alternate and compound.
They have many small leaflets and resemble fern leaves. In the fall brown crescent shaped fruits 6-8 inches long fall to the ground. You can pick them up and shake them to hear their seeds rattle inside like a percussion musical instrument. These trees are very fast growing and very hardy. Such a spineless variety, with an identifying sign, can be found growing out of a hole in the concrete just south of the main west entrance of Galvin Hall.