Nursery growers have been struggling with ambrosia beetles for decades. In the southeast it is
primarily the granulate ambrosia beetle, Xylosandrus crassiusculus. In the Northeast and Midwest the predominate species is Xylosandrus germanus. These are tiny beetles that make tiny albeit lethal holes in trees.
In the past several years a new species has been detected in several states including Florida, Tennessee, North Carolina, and just last month Virginia. This is the camphor shot borer, Cnestus (used to be Xylosandrus) mutilatus, and it is BIG. At least by ambrosia beetle standards this one makes holes as big as a pencil instead of then tiny 2mm holes made by other species. You can find out all about it in a thorough publication from University of Tennessee.
We trap at 5 -10 nurseries every year around Johnston County, North Carolina. In 2011-2013 we captured 1 or 2 camphor shot borers each year. This year we captured about a dozen from at least 3 different nurseries. So it is here to stay and will probably become more of a problem over time.