Garden Pests and Diseases: A weird bug...anyone know what it is?, 1 by kinghippy

kinghippy wrote:
To me it kind of looks like a roach. It has killed one apple tree and almost killed two others. I think it killed my cherry tree, and it is making home at the base of my roses too.

It likes to live at the base of the tree. And, when I water my trees, dozens of them come running out, scattering. It looks like they have been burrowing, because there are dark circles and cracks in the bark at the base of the trees. When I touch the area, it is dry, and there is some sort of sawdust like substance underneath the bark where they have been eating away. Can anyone help me identify it, and I would also like to know how to kill it. I sprayed, but the bugs don't seem affected. All the spray did was kill my beneficial preying mantises. :(

Here's the best pic I have of the nasty little critter. Thanks in advance for your help.