Since you purchased larger trees from a nursery, are they covered by a warranty?

@cecily 7A unfortunately we didn't pay $400 to have them plant them, so there is no warranty.

Don't try to remove the clay - you will damage the roots. But stop the daily watering!! It is rarely necessary for trees planted even in the heat and dryness of a PNW midsummer. And we are nowhere close to experiencing that!! Water only when the soil area surrounding the rootball feels dry at depth.

take a hand trowel.. and dig 3 three to 6 inch holes around the tree .. AND FIND OUT ABOUT WATER AT DEPTH .... then water accordingly ..

you say the clay in the burlap is moist.. is it still wrapped in the burlap??

whats all the black plastic behind.. and is it somehow building and retaining heat.. ... and somehow affecting the tree??? .. cant tell how far away in pix...

in my high draining sand.. for me to water this size transplant tree.. i would have to run the irrigation 6 to 8 hours.. sto get enough water 8 to 12 inches down.. where the roots are..

you need to find out how water moves in your soil.. then learn how to water it properly by hand.. AND THEN FIGURE OUT HOW TO DO IT WITH DRIP IRRIGATION ...

do a perk test to find out about drainage ... which tells you how water moves thru the soil ...

ken

https://duckduckgo.com/?q=garden+perc+test.&t=ffab&iar=videos&iax=videos&ia=videos