My tree don't seem like it's growing. I do water the tree at least 3 times a week. They tell me that these tree's like a lot of water. I dug out some dirt from the bottom of the roots and found a white color stains in the dirt. I wonder if it got a disease? What can I do to correct this problem.
Certified GKH Gardening Expert
White fungus is, typically, harmless and even beneficial. It could be that it is being overwatered. Even though they do like water, they will not tolerate being saturated all of the time, unless it is a swamp cottonwood, or black cottonwood. They will need a little dry period between watering. I would recommend adding dolomitic lime, and wettable sulfur. This should put the soil back into good condition. These trees will just take patience.
This article will give you more information on these trees: https://www.gardeningknowhow.com/ornamental/trees/cottonwood/cottonwood-tree-in-landscapes.htm