Here are some photos of the buds/twigs. Even though both the pot and label were marked "Kousa Dogwood", I think it might be C. florida. I've had a hard time telling from photos of buds on line--there aren't that many taken at this stage that I've seen. Some of the C. florida buds look flatter and less spherical, but the kousa buds look like they have more pointed bracts. There's no sign of a graft, so I don't think it's one of the hybrids.

one should always presume.. they get healthy plants from dealers ... thats kinda the whole point of plant inspectors etc ... you planted it less than 2 weeks ago .. the ONLY thing it could be is.. transplant shock .. could be sunburn associated with the shock .. you and your neighbor have been busy if he cut the tree down in the last two weeks ... whats your base soil ... does it really drain all that rain??.. did you amend the hole with a lot of peat product??? whats the kite string for .. the neighbor on the other side??? .. lol.. that is a shipping stake.. not a proper tree stake ... pic of the whole if you want help with that ... i wouldnt be overly concerned about some leaf coloration.. i would simply make sure it is PROPERLY watered for this and next year ... i dont know if i would move it.. how many hours of sun does it get.. and at what hours of the day?? ken

A kousa in the heat of late summer will typically fold and droop its leaves - it's a reaction to the heat and to conserve moisture. Trees need water just as well as any other plant does in dry conditions, some more than others. You aren't doing your kousa any favors by keeping it thirsty - they are not considered particularly drought tolerant and a periodic deep watering at the root zone would improve its appearance considerably. Trees exposed to continual stress from very dry conditions are far more prone to other problems, like pest and disease issues and winter dieback.

I would water the ground around the tree where the roots are with a sprinkler, rather than watering the trunk with a hose ......and maybe not so much water. It's an established tree and should get by on it's own for the most part. I think you are flooding it too much, causing the weak growth. As long as the lawn is green it should be fine. We have dry summers here near Seattle and I only water Cornus kousas in pots. The rest are doing fine with no extra water, planted out in the landscape. mike