Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory
Emerald Ash Borer
ENT-240-23-PR
January 2023
(Agrilus planipennis [Fairmaire]) Emily A. Parent • Lori R. Spears • Ryan S. Davis • Ricardo A. Ramirez
Do You Know? • The emerald ash borer (EAB) is an invasive pest that is considered to be one of the most destructive forest insects ever to invade the U.S. • Larvae are the damaging life stage. They feed on the vascular tissues of the tree and eventually cause tree death. • EAB is primarily spread to new areas by people moving wood from infested areas. • New infestations are difficult to detect, and damage may not be obvious for years. • An EAB infestation is nearly always fatal to the tree unless insecticides are used to protect trees.
Fig. 1. Emerald Ash Borer Adult Feeding on an Ash Leaf
• EAB has not yet been reported in Utah. To help prevent the spread of EAB, check ash trees for signs of infestation.
Emerald ash borer (EAB) (Order: Coleoptera: Family Buprestidae) (Figs. 1 and 2) is an invasive wood-boring insect that infests true ash species (Fraxinus spp.). EAB is native to parts of China, Korea, Japan, Taiwan, and small areas of Russia and Mongolia. It was first discovered in North America in June 2002 near Detroit, Michigan and Windsor, Ontario, Canada, and is thought to have arrived to North America via infested wood packing material. EAB is generally established in an area for several years before it is detected and can spread over large areas through active flight and human-mediated dispersal. Since arriving in North America, EAB has been found in nearly 40 states, as well as five Canadian provinces (Ontario, Quebec, New Brunswick, Nova Scotia, and Manitoba), UPPDL, 5305 Old Main Hill, Logan UT 84322, utahpests.usu.edu
Fig. 2. Adults Have a Copper-Red or Purple Abdomen
killing tens of millions of ash trees. Since 2013, the westernmost occurrence of this insect was Colorado; however, in June of 2022, EAB was found in Forest Grove, Oregon. If EAB were to be introduced and established in Utah, it poses a serious threat to the state’s ash trees. Ash comprises up to 30% of the urban canopy in many Utah communities, so EAB’s presence would make a noticeable impact. EAB infestations may have contributed to five ash tree species (F. americana, F. nigra, F. pennsylvanica, F. profunda, and F. quadrangulata) being classified as critically Page 1