Well I definitely have some mite issues going on. Looked at the leaves under my printer's loupe and saw very small, white (maybe clear) mites. Didn't see any webbing, so can't tell exactly what type of mites they are. I sprayed with Spinosad about a week ago but apparently it didn't do the trick. I'll see if there may be a "catch all' spray or oil to use.

Wolfridgeil - I too thought it odd that the damage started primarily at the leaf tip. My suspicions right now are either the Spotted Tentiform Leafminer or the Apple Leafminer, but I'm still not sure I have a positive ID. The damaged leaves visible in the second link you provided look very similar to the leaves on my trees, although the larvae were much, much smaller than the caterpillar pictured. In an effort to rid the trees of the problem, I took the time to pinch each "tent" that had formed, with the intent of killing whatever larvae resided within. Barring a second generation of the pest, this should rid my trees of the problem for this year. Interestingly, it primarily affected only two of the six apples trees. Bradybb - If you have fruit trees that are displaying similar symptoms, be sure that small "tents" aren't forming on the leaves. If they are, I encourage you to open one up to see what you find.

Thanks a lot for your advice. I am gonna research both the gritty mix and the 5-1-1. Since I need to re-pot because my soil is wrong, do you suggest that I shake or remove much of the old soil from the roots when I replant? When I was videos on re-potting, they seem to transfer much of the soil but I'm concerned that it will also carry the problem to the new pot. I wasn't able to find the 5-1-1 online. Do you have a suggestion on where to get this?

Salt buildup. After flushing the soil the new leaves will be fine but the afected one will still die. Your tree is begging you to remove the pot with soil from the bigger fake one. Carbon dioxide is heavier than air and it will acumulate inside the big pot, suffocating the roots. Roots needs oxigen!