Emerald Ash Borer and Birds
Minnesota ash trees are on the cusp of a massive die-off
In the past few months, I have been constantly seeing - thanks to the woodpeckers - signs of active emerald ash borer (EAB) infestations on many trees in my neighborhood. The woodpeckers flake off the bark exposing the lighter wood underneath which then becomes an easy tell-tale sign that the tree has an infestation.
Once I figured out what this was, now I am noticing it everywhere. It is alarming to think about how many trees will be dead in the next few years.
Here is some crucial information from the University of Minnesota Extension:
Trees are often killed in about four years, although it can take as little as two years. When trees are first attacked by EAB, the symptoms are hard to notice.
During the second year, woodpecker pecks and thinning foliage begin to be apparent.
By the third year, woodpecker activity is more common and canopy thinning is more pronounced.
You may see vertical bark cracks due to the tree trying to heal over old galleries.
Although woodpecker activity and vertical bark splits are not always caused by EAB, they are common symptoms in EAB infested ash trees.
By the fourth year, the canopy has seriously declined and may even be dead.
It appears that woodpeckers, nuthatches and brown creepers all relish the non-native EAB which may help slow down, but unfortunately not control, the march of destruction that has begun to Minnesota’s ash trees. A bird study conducted in Michigan, where the EAB was first discovered, showed that red-bellied woodpecker and white-breasted nuthatch populations in particular benefitted from the introduction of this non-native pest.
We are about to find out how this radical change in our woodlands is going to affect many species - including us having to deal with a sudden overabundance of dead trees everywhere. What is heart-breaking to fathom is the fact that Minnesota has nearly one billion ash trees, making the state one of the largest concentrations in the country. Follow this link to an interesting read about Minnesota’s prominent ash species, the Black Ash, which has essential environmental and cultural significance. Wood from Black Ash is used by many Indigenous peoples to make baskets.
Here is a key fact about containing the spread from the University of Minnesota Extension:
Don't move firewood.
Most EAB will generally move only about one-half to one mile a year from infested sites. But with help from people, it can travel hundreds of miles when carried in firewood and other wood products or nursery stock.
Don't transport firewood when you go camping or are buying it for home use. Buy the wood you need at local sites or at the campgrounds you are visiting.
And more information on the EAB life cycle :
Emerald ash borers generally have a one-year life cycle that can extend to two years in a vigorously growing tree.
Adults emerge from ash trees any time from late May to August.
After feeding on leaves, adults mate and females lay eggs on the bark or in small cracks.
Eggs hatch in seven to ten days.
The larvae tunnel under the bark of ash trees and feed until fall.
The fully grown larvae live through the winter in chambers constructed under the bark.
They transform into pupae in early spring.
Here is the concern about removing infested trees from the Wisconsin DNR Forestry News:
What Makes Infested Trees So Dangerous?
The structural integrity, or strength, of ash branches and tree trunks begins to decline as soon as the tree becomes infested and the wood begins to dry. Lower moisture content increases the risk of branch and trunk breakage, and the timing of breakage is usually unpredictable. Infested trees may also have total trunk failure soon after death, further increasing the chance of dangerous impacts to people and property.