I have seen that last spring on my trees, but it's only on new growth which is just emerging. The tiny leaves fall off and never see the problem again. I don't know the cause. I just make sure the tree isn't over watered and kept in sunlight in the spring.

Were those leaves too close to the lights? I notice that my trees grow their new leaves towards the lights until they hit them and get burned.

Boron deficiency?

I have those, too. I think it’s because of these bugs sucking on the leaf.

Well dang Nancy, I found some of those black marks on my trees this afternoon. I just pulled them off. As I was inspecting my trees I found some interesting colors on my leaves. I just added Osmocote Plus to some of my trees on Sunday and on some about a month ago. I should have written down which tree this was as I keep a journal. I can just kick myself for not doing so. I am considering adding fish emulsion to see if it will fix my discolored leaves. I have never seen this before. They are half light and half dark. Dark green in the middle along the main vein and light everywhere else. It runs the length of the leaf if I remember correctly. More research needed.

I know they weren't outside, but that looks exactly looks like a little frost or freeze damage. Had plenty of that on our new tender growth after two cold nights a few weeks ago. Established growth did ok, but the new growth took a little hit. The leaves will fall off.

Thanks Ed....mine were definitely not exposed to frost or freeze. Doesn't get any colder than 68* in my little indoor greenhouse. Denise, very interesting. I pulled my ugly leaves too and see if this goes any further.

I sometimes see leaves turn black and shrivel if I let the soil get too waterlogged.

Nancy, did you recently have That tree delivered? My new sanguinelli has the same issue on the newer leaves - it spent the night in Illinois on its way to me and suffered freeze damage on the top 10% of the tree. All of the new leaves in that area have black spots at the tips.

Hi Kelley. No my tree isn't new to me. No more black spots have appeared on the tree so hoping just some weird thing. Sorry about your little tree. Hope it recovers quickly.