Emerald Ash Borer

pests , trees , emerald ash borer

With all the news regarding the Emerald Ash Borer, we are getting many inquiries. Ranging from beetle identification to panic about what to do, we get calls and visits daily regarding this exotic pest. I’ll try to summarize the highlights about this insect.

The Emerald Ash Borer is considered exotic, because it is not native. Since it isn’t native, it doesn’t currently have any natural controls to keep it in check. The frightening aspect of the pest is that it can attack healthy trees. Most other borers attack only stressed trees. The good news is that it doesn’t appear to be a problem in the Peoria area yet.

The Illinois Department of Agriculture has taken aggressive steps to determine the actual status of this pest in our state. 5,000 traps were placed throughout Illinois to determine where the borer is active. The traps are being taken down now, but it will take a couple of months to analyze the large volume of traps.

The insect found in Bloomington appears to be isolated at the moment. They were not able to find an infestation in the area around where the beetle was located. They believe it was brought in from someone who transported the pest in firewood. However, there was an infestation found in Chenoa, IL that appears to have been there for awhile.

What does this mean to homeowners?

1. Don’t bring firewood in from other areas. The borer cannot travel far on its own, so hitching a ride on a load of firewood is the most effective way to transport exotic wood boring insects.
2. The adult EAB is a mall, slender, green beetle that can fit on a penny.
3. The larval stage feeds under the bark of the tree; you won’t see it unless you cut into the tree.
4. The borer is very slow moving unless it is aided by humans.
5. You don’t need to treat your ash yet. The University of Illinois insists there is no need to treat until the insect is verified within 15 miles of your home. Some companies are advertising that you must treat your ash trees now, we do not consider this prudent. First of all, as we mentioned, the EAB is not yet present in Peoria, so chemical treatment is premature.
6. Stressed and weakened trees will most likely be attacked first. Keep your tree healthy for the best control.
7. If the insect becomes numerous, it is then that healthy trees become infected.
8. Once confirmed in your area, the U of I believes you will have adequate time to inoculate your ash tree(s) against the Emerald Ash Borer.
9. Because it is slow to spread, you will most likely to have 2 years to get your tree treated if you choose to, before it might attack your tree.
10. Emerald Ash Borer is not known to attack any other species but ash.
11. When and if you decide on a chemical treatment for your ash trees, you can treat the tree(s) yourself with imidacloprid. It is easy for a homeowner to apply imidacloprid. It is available through several brands such as Fertilome and Bayer. This gives 90% control, which the U of I considers to be excellent control measures.
12. If you are applying the imidacloprid, it requires annual applications. It takes 2 years before older trees are fully inoculated.
13. There is some concern about the affect of imidacloprid on bees. While it is not substantiated, consider whether to use an alternative control when available. Since bees do not pollinate ash, imidacloprid for ash should not be a threat to bees.
14. A tree service can apply Tree-Age. This control can give up to 2 years of control. A homeowner cannot apply this.
15. Ash trees can be subject to many problems. If you have problems on your ash, and the EAB is not in your area, there is likely to be another cause.
16. EAB cannot be detected until it has been in the tree for a few years.
17. Early detection requires destructive measures to the tree. Such methods are reserved for areas where EAB is confirmed.
18. Per the Illinois Department of Agriculture, symptoms of EAB-infestation include decline, crown dye-back, D-shaped exit holes, excess woodpecker damage, basal sprouting, and larval galleries.
19. If, after consultation with a local expert, an EAB infestation is suspected, you should contact the Illinois Department of Agriculture at 1-800-641-3934 or the EAB USDA hotline at 1-800-322-4512.

Eventually, a homeowner may want to consider whether his or her tree is worth the annual cost to treat against EAB. This is a choice the homeowner must make. While we at Hoerr Nursery are no longer selling Ash trees, it is too early to give up on your tree. Perhaps treatment options will improve in the future. Time will tell what action you need to take in your area. For now, keep your eyes and ears open. When conditions or treatment options change significantly, we will keep you updated!

--Dave

 

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Emerald Ash Borer Blog Update

pests , trees , emerald ash borer

This article is in response to the Emerald Ash Borer post on August 28

I attended the Chenoa Emerald Ash Borer Field Day on September 4, 2008. Experts on EAB from various State of Illinois Agencies provided the most up to date information available. Here are a couple of important points I wanted to add:
 

1. Contrary to advertisements by some tree services, Ash infected with EAB can be saved. To say, "Once an Ash tree is infested with EAB it is too late" is false information. EAB can be controlled in an ash that has been attacked by EAB, even up to 30% of the tree.
2. They reiterated that EAB moves only about 1/2 mile per year on its own. Therefore, the University of Illinois strongly believes that once the borer is found within 15 miles of your ash, you have a real good cushion of 7 years or more to get the tree treated.
3. Treatments against EAB must be done forever, like over a million years. So you will want to weigh the costs of treatment. Many municipalities are opting to remove ash in public areas rather than treat them, due to the cost.
4. Only Ash in the genus Fraxinus are susceptible. Mountainash, which is in the genus Sorbus, is resistant.
5. Damage most likely starts in the top of the tree. Early, D-shaped exit holes will not be noticeable from the ground. Other ash problems can also cause the top of the tree to thin out.
6. The Illinois Department of Agriculture recommends you contact a local expert to identify an insect that you suspect may be Emerald Ash Borer before calling them. You are welcome to bring your sample to Hoerr Nursery for ID.
7. The big purple traps are still hanging around, so it will be awhile before we hear the results for our area.
8. Most EAB have a one year life cycle. For larvae that hatched late, they will have a 2-year life cycle.

For more information about the Emerald Ash Borer, visit: www.IllinoisEAB.com

 

-Dave