aspen canker management
My 20 foot Aspen has black runny areas around the trunk but not girdling yet. Any suggestions for keeping tree alive as long as possible? Would a drench of weak sodium bicarb help? I'm in N.Mex at about 8K feet.
San Miguel County New Mexico
We apologize for the delay in answering. We are not yet fully staffed with eXtension experts in the area of your question.
In short, you need to clean the wound, pulling off dead bark and scraping it. If it is an older wound the tree may be trying to heal itself. You will see a swollen area around the wound. This is called a callous. Do no disturb this area, or you will cause more damage. Use a clean knife to scrape bark and debris from the area, being careful to not disturb the area that is trying to heal. This needs to dry out. Keep your tools cleaned, especially before using them on any other trees.
The sodium bicarb may help clean it, but it won't kill the fungi that causes the ooze.