anyone recognize this? should i be worried? seems to happen only after bine gets at least a few feet high and the leaves get a certain size, though not all leaves have it. this is in Tucson, Arizona, first year of growing.
thanks,
Most likely a nutrient deficiency, or a disease caused by the plants weakening due to a nutrient (or water) deficiency.
I would fertilize and water thoroughly. Not sure what your weather has been like, but the ground really needs to soak for a long time if there hasn't been rain for awhile.
It actually looks like Prunus Necrotic Ringspot Virus (PNRV). I guess what happens is that when the affected areas begin to coalesce they form circular patches/ringspots which can be seen near the center lobe of the leaf in this picture. I noticed this on a Cascade plant a while back but it's nothing to be concerned about. At least the plant didn't seem to mind it.