I planted a red oak tree about a month and a half ago. All was well until about a week ago, and now all its leaves are dried up and it looks bad. I suspect overwatering, but I'm not sure. I pulled all the mulch off and sure enough the tree could shift if you move it by force. I grabbed some mineral spikes and easily pushed them as far as I could around the tree, in hopes that it might help. Did I do the right thing, and is there something more I can do to try to save it?
Saving a Drowning Tree
How much and how often have you been watering? How large is the tree? How deep was the mulch? Does the location drain well?
When sending a tree or shrub home with someone, I always recommend the equivalent of 1" water weekly, about 5 gallons. This would suffice for almost any plant up to 8' tall with a spread of 4', and trunk diameter up to 1-1 1/2 inches. Larger plants should have 10 gallons weekly. Mulch should not be over 4'' deep, or the tree could smother.