Oak Tree & Carpenter Ants

Q: I was reading "Oak tree left with hole and ants". You said ants would not hurt the trees. I wanted to know if that included carpenter ants, the large black ones?

I also have another question, on the base of the trunk of at least two of my oak trees there is white foamy stuff. It does have an odor and it attracts several types of bees, gnats, ants and I have seen butterflies there too. Can you tell me what it could be and what to do about it?

Here is a picture I took of one of the bees on the tree at the site, can you tell me what kind it is.

A: Carpenter ants generally colonize just the decayed portion of a tree, so they are an indication of decay somewhere within. If you find sawdust, it's ants bringing it outside as they clean out the interior.

So, any time you see sawdust and ants (or just sawdust alone), you want a professional to check out your tree.

Your oak appears to have a bacterial infection associated with a wound it has somehow received. Sap is oozing out and fermenting, which attracts all sorts of insects. It sometimes smells like day-old spilled beer due to the fermentation process.

The thing to do is clean the oozing area with a direct stream of water from the hose as often as is needed to keep it clean. Eventually, the wound should close itself over and stop oozing, thereby eliminating the attraction of insects.

You don't need to paint the wound or apply anything else to it, just keep cleaning it, sometimes with the aid of a soft-bristle brush if the ooze and foam is too thick.