Oak leaf gall. I've got a collection of these that I find in the leaf litter of our woodlot. They are most likely created when a wasp lays an egg on the surface of the leaf. When the egg hatches an enzyme is released causing the gall to form. #thenatureofkansas #naturephotography #naturalhistoryphotography #nikon #insects #oakleafgall #macro #macrophotography #franklincounty #kansas (at Centropolis Township, Franklin County, Kansas)












