Q & A on EAB


EAB is a highly destructive, non-native insect that infests and kills ash species (Fraxinus spp.) Currently, EAB is responsible for the death and decline of tens of millions of ash trees in the United States. Pesticides can serve as a control for EAB but they are not a cure.

If you need your ash trees assessed, give us a call or fill out the form below.

Questions: What is emerald ash borer? 

Answer: The emerald ash borer is a type of beetle that develops under the bark of ash trees. Its scientific name is Agrilus planipennis. It is a type of beetle in the family Buprestidae, which are known as metallic wood borers in their adult form and flatheaded borers in the immature stage.

Question: Will EAB kill my tree? 

Answer: Yes there is no natural control to keep the insect in check. The larval stage of EAB feeds under the bark of trees, cutting off the flow of water and nutrients. Infested trees gradually die over a period of approximately two to four years. Right now the only way to keep your tree alive is with a preventative Spray.

Question: Where did the emerald ash borer come from?

Answer: The natural range of the emerald ash borer is eastern Russia, northern China, Japan, and Korea. Before June of 2002, it had never been found in North America. 

Question: What size tree do they attack?

Answer: Trees of all sizes can be attacked, from 1/2-inch saplings to the largest, most mature trees.

Question: How did it get here? 

Answer: We don’t know for sure, but it most likely came in ash wood used for stabilizing cargo in ships or for packing or crating heavy consumer products.

Question: What types of trees does the emerald ash borer attack?

Answer: In North America, it has only been found in ash trees (Fraxinus species). 

Trees in woodlots as well as landscaped areas tend to be most affected. Larval galleries have been found in trees or branches measuring as little as 1 inch in diameter. All species of North American ash appear to be susceptible. Ash trees commonly grow in Colorado (include green ash (Fraxinus pennsylvanicus) and white ash (F. americana)). Both are highly susceptible to emerald ash borer. 

Question: Is mountain ash susceptible to emerald ash borer?

Answer:  No. Despite the name, mountain ash (Sorbus species) are very different types of plants and are not attacked by emerald ash borer.

Question: What do emerald ash borers look like?

Answer: The adult beetle is dark metallic green in color, 1/2 inch long and 1/8 inch wide. The larvae, which are found under the bark, are a type of flat-headed borer that is pale-colored, has an elongated body, and a slightly flattened area behind the head. There are numerous sites where one can find excellent images of emerald ash borer. Several are accessed through the national emerald ash borer information website

Question: What are the signs of an EAB infestation?

Answer: This insect is very difficult to detect because it is under the bark, but here are some signs to look for.

(1) branches without any leaves, especially at the tops of ash trees

 (2) vertical splits in the bark exposing S-shaped tunnels

 (3) wild leafy branches (new growth) sprouting from the trunk and 

(4) D-shaped exit holes. 

If ash trees display multiple symptoms, it is likely an indication of a multi-year emerald ash borer infestation.

eab d holes

Question: Are there any Insecticide options for controlling EAB?


1    Imidacloprid Is a soil injection or drench that is done in Early to mid-spring to mid-late fall. Best done on trees from 1 to 10 inches  DBH (diameter at breast height). This is done every year.

 2   Emamectin benzoate: This is a trunk injection done from Mid- to late spring after trees have leafed out. Best done on trees 10 DBH and bigger. This is done every 2 years.

Questions: Is there a trap and lure for EAB?

Answers: Yes Please check with your city for more info.

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