Turning a maple’s gray days to sunny ones

Q: My favorite Japanese maple tree is thirty years old. Two years ago, I noticed that many of my trees were covered with a gray fungus. Limbs and branches got brittle and branches fell. How can I save the one maple tree remaining?

A: The simple answer is to give it more light. The gray scaly stuff on your branches is a colony of lichens. They don’t harm your trees, they just use the bark to hold on. Lichens grow when a tree becomes less leafy due to outside forces. I imagine that over the years, your landscape has become more shady. Your Japanese maples lost leaves as a result. Now the lichens have a perfect environment on the branches. If you want to save your maple, one option is to prune branches overhead to admit more light. If it’s truly your favorite Japanese maple, you might consider moving it to a more sunny spot.