Question
I have a very tall poplar tree that is rotting inside the trunk from the ground up to 2 feet high. I did not notice any carpenter ants around. The tree is still producing leaves over most of the tree but some limbs are bare.I would like to save the tree if possible. What can I personally do to save this beautiful tree?

Answer
When the bark of a tree has a wound this will allow decay fungi to enter the woody part of the tree. The fungi will continue to decay the wood on the inside of the tree trunk. This is a very slow process. This decay over tome will make the tree trunk hollow. This does not effect the health of the tree except from structure stand point it may weaken the trunk or limbs causing them to break during high wind.
The best thing to do is to keep the tree healthy by adding fertilizer. Next spring add fertilizer at the rate of 2 lbs of 10-10-10 for every 1 inch of trunk diameter (a 12 inch diameter tree needs 24 lbs of fertilizer.) spread this over the ground around the tree. The root system will spread about 1 1/2 times the spread of the branches so put the fertilizer from about three feet from the trunk to well beyond the ends of the branches. water this into the soil good. DO NOT use a fertilizer for lawns containing a herbicide like Weed and Feed just slow release regular 10-10-10.