The leaves of my aspen have been turning brown around the edges and some are dropping. What should I do?
The problem sounds like leaf scorch, which is caused by lack of water. But that doesn't mean adding water will fix the problem. Anything that damages roots can cause scorch, since poorly functioning roots can't absorb water well. Insufficient water, excess water, compacted soil, root competition among trees, shrubs or turf and lack of winter water can all cause scorch. Improve the vigor of the tree throughout the year through proper watering, fertilizing and pruning. Apply water to the root area monthly from Nov. through February in the absence of sufficient rain or snowmelt. Roots will absorb water throughout the dormant season when soil temperatures are higher than 40 degrees.