Surprise! Emerald Ash Borers have an Appetite for White Fringetree Too!

In 2002, the nursery and forestry world in the Midwest was turned on its head with the identification of the ash-killing emerald ash borer in the Detroit, Michigan area. This Asian import has gone on to kill millions of ash (Fraxinus spp.) trees throughout the midwestern and northeastern U.S. and southern Canada. As of 2015, this beetle can be found in most states east of the Mississippi, except for a few southern states, and it made a long distance jump to Colorado a few years ago. Soon after its detection in North America, laboratory and field tests of the suitability of different hosts for this beetle were conducted. This was important because, although emerald ash borer had only been reported on ash species in China, some other species are reported as hosts in Japan and Korea. The focus at the time was on some hardwood trees related to ash, like walnut and hickory, as well as some popular ornamental shrubs including lilac, forsythia, and privet. The latter three species are members of the same family as ash (the Oleaceae, or Olive family). The upshot of these tests was that ash and only ash appeared to be suitable for the complete development of this beetle in North America, and field observations made post invasion had not proved otherwise… until 2014