Hortiscope: Don't use nails if plants have an iron deficiency
Q: I have a 12-year-old river birch that keeps dropping small limbs, but it looks healthy. I seem to remember hearing something about possibly some type of worm that may be causing this to happen. I don't see any signs of where a squirrel may be doing the damage. The limbs that are falling off are blunt at the end, so they look like they have been cut with a sharp object.