Emerald Ash Borer
Emerald Ash Borers (Agrilus planipennis) are a destructive wood‐boring beetle of ash trees (Fraxinus spp). Native to Asia, the Emerald Ash Borer (EAB) was unknown in North America until its discovery in southeast Michigan in 2002. Since then, the invasive pest has spread to 35 states, including Texas. (Map of EAB detections in North America and Canada Opens in New Window )
The EAB is responsible for killing millions of ash trees across much of the country. It reproduces by laying eggs inside the bark, disrupting the flow of water and nutrients through the tree, and ultimately killing it. EAB’s enter communities and devastate all of the Ash trees, leaving very few survivors.
Signs of an EAB infestation may include any or all of the following:
• Dead branches near the top of a tree (it must be an Ash tree)
• Leafy shoots sprouting from the trunk
• Bark splits exposing larval galleries in an “S” shape
• Extensive woodpecker activity
• Small D‐shaped exit holes
The EAB is very aggressive, causing ash trees to die within two or three years of becoming infested. EAB on its own travels approximately 3 miles per year, but with human intervention it has spread across the country in less than 20 years. Transporting infested wood, especially firewood, has spread EAB across state lines in a matter of decades.
Based on Plano’s 2014 iTree Eco analysis, 6% of the tree canopy, on both Public and Private properties, is made up of Ash tree species, which means Plano’s tree canopy WILL be impacted by this invasive, exotic insect.
First, it must be noted that EAB has not been found in Collin County. Second, EAB attacks Ash species and no other tree species in our area is in danger of this beetle.
In 2016, the Urban Forester recommended discontinuing planting new Ash trees in the City of Plano.
In January 2019, Plano Parks forestry crew members began removing Ash trees on public property (parks and median street trees) that were inventoried as ‘fair to poor’ condition or in decline. Ash trees that are scheduled for removal will have green notices of removal posted on them 10 days prior to their removal (Tree hanger notice Opens in New Window ).
Plano is currently focusing on public property such as parks, medians, right-of-ways and municipal buildings.
Replacement is also a top priority, while continuing to diversify tree species composition on Public property. Our goal is to continue to grow Plano’s canopy to 30% and slowly reduce the negative impact of this insect.
Residents who wish to save their ash trees on private property should consider the systemic insecticide TREE-äge, Emamectin Benzoate: 4.0%. This will not be necessary until EAB has been discovered within 15 miles of Plano’s city limits.
Texas A&M Forest Service is monitoring the situation and provides additional information about EAB on their website.
If you have EAB specific questions, please contact Mike Sills, Texas A&M Forest Service at 972-952-9242. If you think your tree may be infested, contact the Texas A&M Forest Service Hotline at 1-866-322-4512.