Red Sunset maple leaves curling in June. Why?

[shawn_meyer]

I bought some maples last October- 3 autumn blaze and 3 red sunset. They were discounted because they were so large and the nursery needed to move them out. They were in containers that were practically solid roots. They are about 18 feet tall and about 4 inches in diameter. They leafed out nicely this spring but the red sunset maple are all now curling and turning yellow. I'm sick about this. I also bought a honey locust that is turning yellow.

We had about a month of solid rain but it was never standing where the trees are. About a week ago, I pulled the mulch back to help the ground dry out. I noticed quite a few antes. Don't know if they can harm the trees. No signs of other insects.

I also wondered if the roots were girdled. They guy who planted the trees didn't do much to untangle the roots.

I had staked the trees in the fall and the ropes that held the tree were very tight against the truck (about 5 feet off the ground). I cut them off today. I'm probably just grasping at straws.

I'm desperate to save these trees and will try just about anything. Anyone have any advice? THANKS!

 

[shawn_meyer]

Forgot to mention that the guy from the nursery suggested I drill holes about a foot beyond the root ball and fill them with high phosphorus grass fertilizer in order to encourage the roots to spread out. I did that but I don't know if that has any bearing on my inquiry.