What makes you think they look like they are getting too much water out of curiosity?

Because when they get too much water, i.e. the soil is too dense and the roots can't breathe, that's what's happened in the past.

Right, but I wondered what it was about the appearance of your leaves in particular that made you think that was the culprit?

I don't. That's why I'm asking. Note the "as though..."

What's going on weather-wise? High temps? high humidity? heavy rainfall? Whatever is the issue, it is cultural, not pathogenic.

I'm thinking it's the unmitigatingly high, 14 days over 90F heat. Just paranoid. :)

It may very well be the heat. I've been struggling with similar issues on several potted tree species + some in ground items. Miserably hot- record temps 90's and 100's. I've put up shade 'sails' on all plants with leaf issues and it is working. Old sheets, landscape fabric, anything light/airy and easy to attach/hook through/tie to poles, lattice etc. Good luck!

Discouraging. Poor things are so beautiful and I have NO SHADE. I'm going to have to figure out some 'sails' myself. Thanks.

I've pushed a lot of my potted stuff together so they can help shade each other and keep the pots cooler too + easier to set up a group shade cover. So done with this heat!

I think I'm just going to move everything under my single, mature tree and let the underneath garden stuff fry. It's mostly weeds where I sit these pots. Of course, there is a frog living in a soup kettle in the middle. Might have to rethink this.

Any idea what THE fastest growing tree is? I want a couple.

Heh- I've been going round & round with that but my tree space is sadly finite so I'm putting in the biggest versions of my 'perfect' trees that I can find/afford in area nurseries. Then I'll give them the best cultural care I can for maximum growth. River birch is generally a good fast tree (borer resistant) but so many of the really fast growing ones are fraught with issues like weak wood, surface roots, messy etc--poplar, willow, and silver maple come to mind. Also kind of depends on where you live- certain diseases and insects may be present/absent and that will affect options. Here are a couple of articles I've encountered in my searching... http://www.thisoldhouse.com/toh/photos/0,,20355714,00.html

http://www.finegardening.com/fast-growing-trees-avoid

I noticed White Pine is on both use/don't use lists! Again, probably depends on location for some trees. Small to medium trees that I've had good luck growing -fastly- which also seem to love heat (and deep watering) are Crape Myrtle and Seven-Sons-Flower (great small tree), also Cryptomeria 'Sekkan Sugi'. -Sigh- I love trees, why can't I have 5 acres like my sister?! Well, enjoy your trees, whatever you wind up with- your Japanese maples are lovely, even if they're a bit crispy this year! Just save a spot for the frog:)