There are two in this picture [small middle, large right; the big middle (behind) is a black walnut tree] - it's not quality photography, as it was taken with a cheap point-and-shoot a couple years ago. Since it was taken in early July, instead of what you posted, you see the light colored "flowers" which turn brown and fall prior to making the nuts (around mid-late July). I can still remember forgetting to keep shoes on and accidentally stepping on those spiny things when they finally fell in late September/October.
