Do you have Ash trees in your landscape? If you live in many areas of the East you might have heard of this pest. Cornell calls Emerald Ash Borer (EAB) the “tiny green killer.” It was found in Detroit in 2002, and now has spread to 15 states and two Canadian provinces.
Before I get into this long post and bore your socks off, especially if you are not a gardener with ash trees on your property, I have a great, short post on Nature and Wildlife Pics, my new blog. It is a story, one almost so unbelievable to have happened, on dragonflies. You will find it entertaining – Story of the Web Stuck Dragonfly.
This post on the Emerald Ash Borer will prove very enlightening to those interested. Rather than regurgitate information from government websites like many might, I am giving you first hand site documentation as we learned it from the DEC.
I was on a trip Saturday hosted at the Reinstein Woods Environmental Education Center. It was a workshop offered by Cornell Cooperative Extension and the New York State Department of Environmental Conservation.
Participants, of which I was one, learned about the issues surrounding EAB and the economics of addressing an infestation.
Do you know how to look for signs and symptoms of an EAB infestation in ash trees on your property or in your community?
Probably not since it usually requires special knowledge and equipment by those validating infestations in an area. We were taken around the park by our knowledgeable DEC representative being shown trees affected. We saw the damage and located borer larvae.
Below is the EAB larvae gallery. May through July is the time to see the adults emerge.
A tree being inspected and tagged.
Woodpecker holes, about 1/2″ OD, in the tree indicate they may have been feeding on the EAB. Woodpecker holes are larger than EAB holes, and not made in a D shape. Both type of holes are shown above and below. The EAB hole is 1/18 inch OD. Woodpeckers are identified as a natural predator of the EAB, but unfortunately, they do not consume enough of them. Cornell has a field guide that also has the information I have posted only it is more inclusive and detailed. Here is a link to the Cornell downloadable pdf, eabfg.
In NY, the ash borer has infected many ash and it is looking rather grim for ash trees at this point. Many are being felled to try to mitigate the spread, but that is also a way in which the borer is being spread too. People are using and selling infected wood for firewood, and by the time the wood is dried, the borers are hatched and off in a new locale to infect more trees. This beetle has the potential to forever change the face of our NY forests and woodlots. These trees comprise 10 percent of NYS forests.
This workshop was geared to train Master Gardeners and Master Forest Owners to engage local forestry, landscape/nursery businesses, and communities to increase the awareness of the EAB. I was given a number of educational handouts to distribute for help with ID and who to contact, so I thought to spread the word by doing this post. This one has the NYS DEC contact information, but I imagine your state has a number as well.
If you want one and I have enough left over, email me and I will send you one. It really is handy.
You can see their size and metallic green color. Our instructor did not locate a live adult for us, even though he had the net at the ready.
So how do you help?
One reliable way to find out if your area has an infestation is to watch a wasp. The female Cerceris fumipennis is a ground nesting parasitic wasp and collects buprestid beetles to line her nest. Locating the wasp is a way in which to monitor for the EAB. But there are other ways which we learned and I will share.
Other ways to look for an infestation is to look for the telltale markers, like the crack above or the canker below.
They strip or shave the bark off with a special knife at a trunk suggesting a gallery. Under the bark you see the gallery where the larvae tunneled.
I did ask about the harm done to the trees from his bark removal. The instructor said that the trees are already doomed and this would not matter. He also mentioned they intentionally create these wounds or even completely girdle a tree to encourage borers for study. Since it is an attractant, that also brings borers into an area to trees yet infected, so it is something being weighed for continuing the practice.
Another question I asked, does it affect all ash and he said it does, even Asian ash species. Some Asian trees do have natural resistance though.
A tree that is compromised is very likely to get EAB if it is in the area. Two other issues affecting the Ash are Anthacnose in shade trees and Ash Yellows. Here are two examples of each.
A big problem with the ash dying is ash grows rather densely in the forest. This leaves large areas open which changes the ecology of the forest. Different species of plant fill in the open areas and habitats change.
I then asked about what happens to the dead trees? He explained they are removed and destroyed. Since those still standing had woodpecker, owl and flicker holes I asked about their removal and is not leaving the trees better for the wildlife that build homes? He told me something very good to know.
Only four dead trees per acre is recommended to provide for wildlife. More would be no better because of competition between inhabitants. So this means that other tree species fill in for that purpose, plus ash is too hard a species for many of the animals that would make tree hole homes. Very good stuff to know.
I wish I had good news to report, but the only way to save a tree is to get it injected. The cost is around $100 per application depending on where you get the quote and the size of the tree. It is not cost-effective to try to save a wood lot, only a specimen tree. I hope passing on what I learned first hand will help you ask the right questions and understand the severity of this problem. If only caring about whether baseball continues using ash for bats, or if you are concerned from an environmental point of view, science and the USDA are working hard to combat this pest with no natural enemies to fight it here in the States. Here is an article on the biological control of Emerald Ash Borer. We were introduced to this by the instructor, but it is far too complicated to get into here. If you are curious, see the work being done to date.