Leaves are alternate compound with more than 11 leaflets.
The leaves are double compound, with an almost branch like central stem and are large, 1 to 3 feet long containing 40 or more leaflets. The leaflets are 1 to 3 inches long, dark green above and a yellow-green beneath, sharp pointed at the apex and with margins wavy or almost smooth.
The twigs are very thick, stocky, blunt and marked by unusually large leaf scars and with a large pink pith. On the trunk and branches the bark is rough and gray, breaking into very characteristic flat ridges or plates with upturned edges.

The fruit is a large, broad, stubby, very hard or horny dark brown
pod, containing large, brown flinty, round, somewhat flattened beans, from
which the tree gets its name.
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