In one tree, I found nuts with unusually shaped shucks (photo above). The nuts appeared flattened with a distinctive crease down the middle. Although these nuts had not yet split shuck, the shuck had separated from the shell and I could easily peel out the nut. What I found inside was a small nut with a kernel that had grown too big for its shell.
This condition occurs when nut size and final shell dimensions are determined during a dry period in late July. A lack of soil moisture during the nut sizing period causes the creation of smaller-than-normal nuts. Later, ample rain fell during the kernel filling process in late August which, in turn, promoted rapid kernel expansion to such an extent it popped open the shell. What is interesting to see is how the shuck reacted to the over-expanded kernel. The crease in the shuck is located directly above the crack in the shell. Fortunately, not all the nuts on this tree appeared like this. Most nuts had normal shucks and already shuck split.
Every fall, I enjoy taking photos of ripe pecans on the verge of falling out of their shucks. This year, I found a nut that was not only ready to fall but one that tickled my fancy (photo at right). Almost like a Rorschach diagram this pecan reminded me of something totally unrelated to pecans. Can you see the helmet, eye slits, and open mouth with pecan falling out? Or maybe I have an overactive imagination!