One year they got so bad on our place that I put fly paper strips on the side mirrors of my truck. I drove our long tree lined driveway once or twice and the flys completely covered the fly paper. Put on new strips and repeat. Not sure it helped but few things are as satisfying.
Apparently the beetles bore deeper in the wood than the systemics go. So beyond the xylem and phylum. Once the ambrosia beetles get into the tree they are apparently goners. The systemic fungicides are said to not be effective against the fungus that eventually kills the tree. I will stubbornly...
Ambrosia beetles showed up in seven of my biggest and bearing healthy chestnuts this spring. I did not know what an ambrosia beetle was until three days ago and now I know more than I want to and the news is heartbreaking. I have 148 chestnuts that I baby and to find that these trees are goners...