Can you all see the pictures? Also, on the tree with the fuzzy leaves, on one of the three grafts the leaves seem to be turning a lighter green and losing some of their fuzz - I'm hopefully taking this as a sign that they are maturing and that variety is supposed to have lighter green leaves, rather than that the graft is ill.

Of the four Asians that I planted, back in '96: Chojuro is #1 - big, pretty fruits with great flavor, doesn't tend to overbear as much as the others. Shinko - close second. Heavy bearer, and needs thinning, but even without thinning the fruits size up pretty good(and will break branches), good flavor, but not as good as Chojuro. Niitaka - really overbears, and fruits will not size if you don't thin. Usually lacking in flavor - plenty of juice, but just sweet, with little character; they were good last year, but this year just so-so. Korean Giant/Don Bae - a real 'dog' for me. Never set more than 2 or 3 fruits in a year - they got huge, but were big watery, tasteless things. Kinda like eating a wet raw potato. I didn't shed a tear when fireblight killed it to the ground.

Where are you located? There are a lot of insects that eat leaves. Two weeks if a pretty short period for something to eat most of the leaves on a tree, so something in the grasshopper/locust family could be the culprit. Less likely to be caterpillars in that time frame. You can try putting out a bright yellow sticky trap to catch a few for identification, that might be step one. Could also be something like snails climbing up the tree to gorge at night ?

Asian pears, Pyrus pyrifolia, are no different to grow than common European pears. Just not as cold hardy :-) No specific pH requirements and subject to the same disease and insect issues. I see nothing specifically wrong with those leaves except perhaps some sun and/or drought stress. The discoloration does not look like any sort of nutrient disorder. And I agree that at this time of the season, stressed out leaves is not something I would spend much time worrying about. If you have concerns, just make sure all the leaves are carefully raked up and destroyed, although I really do not think you have anything to be concerned about. And 'early dormancy' might be taken with a grain of salt :-) Trees are coloring up a lot in my area and we won't even have a hard frost until late November or December. Coloring and leaf senescence/dehiscence is a response to shorter day length and cooler temperatures and can happen whenever those conditions are right. The tree will not be fully dormant until all the leaves have been shed.