In my backyard there is a stately cedar elm. I like this tree even though it harbors flocks of birds that poop richly all over anything that doesn’t move; sometimes even if moving. One of its characteristics is that it will drop branches after a stiff wind. The morning after some exciting weather I picked up the aftermath and found these. I don’t believe I’ve ever seen anything like these growths before. (Occasionally after a frost some annuals will ooze ice crystals from their destroyed stems that have a similar form…. different origin and material, though.) This seems to be the result of a mutation. Sure strange things happens in a lot of plants, but what is it that gives rise to this shape on opposing sides of the branch, with striated woody layers showing and all?