What is causing the clumps of brown leaves on trees in Downingtown, Pa
Many trees of all kinds in the area have these clumps of dried brown leaves. Why?
Answer
These brown clumps of dead leaves you are seeing are more than likely caused by cicada damage. from the locusts (17 year cicadas) that climb out to the end of branches and insert their eggs (if you look at them closely you can probably see the slits where the eggs were laid), mostly on oak, maple and fruit trees. Then these leaf clumps die and fall to the ground where the eggs hatch and the nymphs crawl into the ground and feed on various things in the ground for 17 years before emerging as adult cicadas again.