Thank you for your reply, Robert! I was wondering if they might Podgalls, but the photos I find online don't look exactly like what we had. Also, the pictures of the Podgall infested trees that I find online aren't very clear. We have little weird looking pods on some of the tree leaves, but when I open them I don't find anything inside. We normally have a lot of birds around and we have a lot of landscaping. I hope the birds can find them as they are quite small and spread out since I swept them off the deck. I left them on the table for a couple of days, but I guess the birds didn't notice. (The only reason we noticed them was because there was a pile of them on the table and deck.) Was thinking about spraying the tree, but I think it would be a major chore as the tree is so big. Hope the tree survives though. Thanks so much for your time and expertise!