Question
My Mom has a small group of Quaking Aspen that she brought from Utah and planted here in Southern Oregon...they seems to have done pretty well over the past eleven years, although one of the larger ones has a large canker-like growth around the middle of it's trunk....it's almost like rotted hardened wood.  I chipped away at it and some insects fell out and there are some bore holes.  Help!  I would like to try and save the tree!

Answer
I am not sure which canker you might have or if what you are seeing is a result of the borer damage. Here is a web link with pictures of the various canker diseases and their control. Maybe you can tell from the pictures which one you may have. http://www.na.fs.fed.us/spfo/pubs/fidls/q_aspen/q_aspen.htm

I would also suggest that you call the Oregon State Forestry agency and ask one of their Foresters to come out and take a look. Here is the web link to their contact page from there you can select the one closest to you. They also have a good Forest Health section that should be able to help. One of them should be able to come take a look at your trees and advice you,

http://egov.oregon.gov/ODF/offices.shtml

The Forest Health Section contact web link is:

http://www.state.or.us/agencies.ns/62900/00050/00020/00024/index.html