ehBeth, thanks for posting stats each day!
sumac, there are no marks or discoloring on the leafs of the birch. The only evidence of disease is drooping and loss of foilage at the top of the tree. <Figure 5. A classic example of a tree infested with bronze birch borer> the photo featured at the link depicts a birch tree in severe decline. The next set of photos <figure 6> depict stages of decline. I'd say the birch tree a 3 - with little evidence of leaf loss.
Sooooooooooo, I doused the tree with insecticide, and the tree perked!
<be right back>
Ok, its been about an hour since the application, the tree continues to droop but not nearly as much as before the application. Also noticed small bugs flying everywhere when trimming the lawns, so applied more of the insecticide. If there isn't significant improvement <i'll give the insecticide a few days to penetrate the soil and bark of the birch> then i'll remove the tree. <sigh> Not looking forward to chopping down or dragging a 20 foot birch tree away from the property Oy!
On a more positive note, daughter and I had a wonderful day chatting, munching, and smiling. She and son.i.l celebrate their 10th wedding anniversary next month. Couldn't be a prouder mom if I tried...