Agrilus anxius http://www.na.fs.fed.us/spfo/pubs/fidls/bbb/bbb.htm http://www.na.fs.fed.us/spfo/pubs/fidls/bbb/bbb.htm identifying birch-borer damage http://www.na.fs.fed.us/spfo/pubs/fidls/bbb/bbb.htm Agrilus anxius