I'm not sure what to say other than hopefully this isn't bacterial/viral. I've had a ton of ants this year for some reason, and I'm afraid either they (or the pests they've been protecting) have brought on some kind of disease. I've stripped less-than-stellar leaves off of a couple nursery plants, but this showed up on my overwintered reaper plant. This was only on one leaf as far as I could tell.
Anyway, does anyone know what this could be?
Anyway, does anyone know what this could be?