The ones dug in the wild have a much lower survival rate because you are severely disturbing the roots. To be successfully moved, you need to retain most of the smallest roots. In the wild they extend far from the plant and many are virtually impossible to keep. The standard way to improve the odds is to root prune the plant several months before you move it. This involves cutting a circle into the ground around the plant at its drip line with a shovel. This causes the plant to form a root mass inside the drip line which is easier to move.

R. maximum is normally tolerant of sun and shade. However, a plant that has just been moved is highly stressed and may be dissicated by the sun to the extent it dies. When moved, rhododendrons need to be monitored to make sure they don't get too dry. But over watering will kill them also.

Thanks for replying Rhodyman. I am in the north and sun should be not a big deal, but the wild dug survivor is in mostly shade, the crispy critter wild rhody was planted the same time as the survivor, from the same wooded area. They both were shaded by a milk crate ( each separate crate) with a webbed shade cloth over the crate. They were both spring 2012 transplants to my yard. This year the 2 were uncovered in spring 2013. The survivor is shaded by a Chestnut oak besides brief morning sun, the Crispy one is under a Black oak that hasn't gotten wide enough for shading it yet. Well, I should've planted on the other side of the tree, which IS shaded more. Sorry for taking so long to explain. The rare finds Rh. Maximum is 100% shade all day under a Pin oak. I can't find any other conclusion to come to but that they favor tons of shade. As for the Hemlock tree, I may try the full shade thing, just as an experiment in my yard.

I have grown one that I dug from the wild. But the first year I put it in a pot. Maybe even 2 years. Then I planted it. I think that helps sometimes.

Yes, hemlocks like shade.