they are not aquatic plants... GET THEM OUT OF THE WATER .. and get them into mother earth .... now.. please lucy .. splain what you were thinking.. lol .. dig hole.. throw in.. refill.. water IF IT WILL DRAIN ... we do NOT want an ice cube created... then mulch well .... even to the extent of going and buying a couple bales of straw ... and really piling it on ... we will fix whatever we need too in spring.. as soon as the ground thaws ... like proper location.. straightening.. etc ken

See thead on thread page of forum titled "moving mature japanese maple"( about 10 or so threads from top!!!..should answer your questions...David

Sorry I've confused you.Clear the soil and mulch now,the base of the trunk needs to be able to 'breath' and not be buried in damp soil.The trunk should be exposed right down to where it begins to bulge out(called the root flare),immediately above the roots.It's quite common to have to remove 2-3" where nurseries have potted them too deep.If it's not rodent damage it could even be the dampness around the trunk base that triggered the peeling.I suggested autumn as the time to raise the tree up if you think it's planted with the root flare below the surrounding soil level. You can't beat using your hands for checking soil moisture.Use a small trowel and dig down the full depth of the roots just outside the rootball and feel if the soil's nice and damp down there but not soggy.One usually gets some dieing of leaves on newly transplanted trees,especially if your summer's hot.The bark damage isn't helping either.There's probably not a lot you can do about that apart from getting the watering right.Don't be surprised if it loses some more leaves until it starts recovering and settling in. I suggested a general fungicide just as a precaution because the trunk base will be very damp now and it's something most people have in their shed.Don't worry if not have,the important thing is to get the bottom of that tree exposed and dried out so it can heal,and to get the watering right.

I would not plant them closer than half the canopy spread from your arbs. If the Japanese Maple is expected to get 15 feet wide and the arbs 20 then count off 10 feet for the arbs from the trunk and 7.5 for the maple. Oh, and if you are in a cold zone like 5 or 4 pushing the maple's cold hardiness I would HURRY or wait till next year. Good lookin tree btw. What cultivar?