|My tree is about 22' high and covered with brown leaves. The brown seems to be densely speckled, but I can't see any insects. Any ideas what this might be and how to deal with it would help. Thanks.|
|Liriodendron tulipifera is the botanical name for your tulip poplar. It is related to magnolias and isn't a poplar at all! These trees are relatively insect free but are susceptible to a few diseases. However, during hot, dry weather interior leaves can turn yellow and fall off. This condition is due to the weather and is not a disease. Yellowing may be preceded by small, angular, brown spots on the leaves. There's nothing you need to do for your tree. It will recover on its own.
Best wishes with your landscape.