Royal Frost Birch leaves curling

[austindrake]

Hey all - Im growing this 'Royal Frost' Birch, and currently trying to air-layer the top two sections. It's taking it's sweet time, but while I've been waiting i've noticed that it has curled most of the leaves to a large degree. Is this simply heat/humidity stress? It is in a pot and I dont believe my watering routine is too far off the mark.
I dont believe there are any pests (that are visible at least) - I discovered a few spiders who had taken nest but that's no problem (I assume). Any thoughts? Is this even a problem to worry about? TIA.

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[tgward]

is it only the leaves on the air layers or all of the tree

[austindrake]

Whole tree!

[tgward]

check under the leaves for bugs-- if possible remove from pot to check moisture level and root health-replace -if not too soggy I would immerse it in a bucket until it stops bubbling -remove and observe how quickly it drains. Not sure if we have birch borers in aust

[austindrake]

It's a tall tree, but I should be able to remove it from the pot to do that. Thanks for the advice!

[austindrake]

So, definitely no bugs on the leaves!
It has been raining today. The top did look like it had dried somewhat despite the rain today, so I had topped it after work today with a quick spray, so I dont believe the soil is too waterlogged based on the water it's had today. Here is a shot of the roots - they seem to look ok to my green eyes.

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[shibui]

Birch are naturally stream side trees and are normally very thirsty. To my eye those leaves look dehydrated. It may have only been 1 hotter than usual day to cause this.
Roots look fine and plenty of water there now so that it recovers.