The butternut, also called white walnut, is found throughout Iowa
mostly on bottomlands and lower slopes on moist, rich soils.
The pinnately compound leaves are similar to black walnut leaves, being 15 to 30 inches long with 11 to 17 sharp pointed, oblong, finely toothed leaflets 2 to 3 inched long. The leaf stems and leaflets are velvety.
The large, lemon-shaped fruit has a shell which is very rough and sharply ridged, and the kernel is edible. The nut is enclosed in a yellow-green huskwith short, rusty, clammy, sticky hairs.
On young branches, the bark is smooth and light gray. On older branches and trunk it breaks into shallow, flat gray ridges which form a diamond-shaped pattern. The underbark is chocolate brown.