Thanks to those who responded! After searching Google images based on the suggestions, I think it's likely Rhamnus alaternus or Prunus caroliniana, but I couldn't determine specific distinguishing features between the two. Perhaps it will be easier when I see the flowers?

Here I am ...lol Hi Andrew: I most defiantly would make a direct question to "Rhizzo" or "Jean" since they may not even be aware of this problem you are having. I would also look up the Pest and Disease forum since that is where they hang out, and ask the same question there. I can guarantee that you will be helped as fast as lightning since they are just two of many that are always willing to help. They are usually spot on too. I wish I could help, but I have never seen this type pest before and you want to make sure you treat it with the right pesticide if they are pest's. Do they leave a sappy or sticky residue on the leaves anywhere? When did you first notice them? What affect are they having on the leaves? At what temps do you grow them? What is the coolest you can grow them at? Have you tried any sprays yet? Are the trees small enough to wipe these things off with a cloth and water? Sorry for so many questions, but I like a lot of detail:-) Let us know, ok. Hope you are doing good. We can keep these thread going if you wish too. It seems everyone take a break about this time of year, but I find this forum very fulfilling when winter slows me down. Mike:-)

Sorry to post so late to this topic. I just found this place and created an ID just to answer this LOL. It is definately a mullberry tree. I am assuming the berries are white and look a little like strawberries? I have one and I get tons os Cedar Waxwings as well as Baltimoe Orioles and Robins. They eat the fruit until it is completely gone. The Mullberry tree is considered a weed to most but I love my tree. It is right near my porch and I spend a couple of hours every day watching the birds enjoying the fruit. The only downfall is that the berries fall off the tree and can make a mess. To me it is worth the inconvenience though. Mullberry is a favorite for many birds and if you have one in your yard the birds will be there from morning to night.

I was following the directions given by the nursery, but I think I will water every other day this week and then next week only 3 times. Thanks for the advice! LOL...a huge downpour is just starting, so Monday it is.