River Birch dusky birch sawfly
My 'Heritage' river birch is currently infested with dusky birch sawflies. This has happened before and the tree usually recovers with time. My question is that my sidewalk/driveway is covered with little dark brown/blackish "balls" the size of dried peas. They are painful to step on without shoes and are staining the concrete in addition to be messy looking. Are these balls a result of the sawflies eating (poop?) or is it some other issue that I should address? I do not have a way to provide you with an image.
Without a photo we cannot say for sure whether the balls are sawfly poop or galls that may have fallen off the tree or something else. You might try going to google image and putting in birch sawfly excrement and birch galls to see which matches better to what you have. vw
Based on photos on Google Image, the droppings appear to be cicada excrement. When the droppings are fresh, they are a little larger, a dark greenish/brown color and have a pattern similar to a corn cob.
From your description, this may be an immature seed pod and not dried up sawfly poop. Is there another tree nearby?