wow that is a really big mulberry tree. We had two large ones in the yard of my family home, we ate lots of mulberries and so did our dogs and other animals so I don't think that would be the cause. Aspca says non toxic. could the dog have gotten hold of chocolates? That could do it. Here is a link that might be useful: Aspca

Hi Susan, I suspect it must have very tiny flowers when it blooms because I have never noticed the tree in bloom at all - and I'm the type who is always excited to see which of my plants is blooming each day. Do you have any guesses as to what month I should look for them, with berries this size in late Oct-early Nov? Maybe June or July? Thanks, Erin

Gosh, what a shame she pruned it. One of the many ornamental characteristics of a crape myrtle is their lovely 'bones' in the winter when they drop their foliage. That interesting skeleton is especially important in Floria and other semi-tropical locations where deciduous plants are too few and far between. What has been created by the drastic pruning is what most of us would call an eyesore, especially notable in the dormant months. Sadly, your Mother will be pretty shocked when she sees what's going to happen to her tree come next spring. Yikes! Attached is a good link from Clemson with one photograph illustrating a gorgeous and properly pruned Crapemyrtle and another image showing what they end up looking like after "crape murder". Boohoohoo. Here is a link that might be useful: Right way/wrong way

Sometimes a baby tree looks different. Have you looked up ash seedlings? I don't know what it is.