Too late in season to treat Ash with Tree-Age?

[TominKY]

I have about a dozen ash trees on my property that I would like to try to protect against the coming EAB invasion. I am going to treat the smaller ones with Imadacloprid applied to the drip line roots, but the larger trees will be treated with Emamectin Benzoate using the Arborjet system. However, now that the hot, dry dog days of summer are setting in, I am worried about uptake and wonder if I would be throwing money away. Would it be better to take my chances and wait until next spring to treat them? I am not currently seeing any signs of active infestation, but I know that EAB has been found in my area. I have had a couple of local arborists evaluate the trees and give me estimates, but I don't want to spend the money needlessly. I would have to hope that they would be honest with me if it is too late to treat the trees, but you never know.

If I proceed with the treatment this year, I assume I should wait for a decent rain event, right? Has anyone had any luck treating with trunk injection in the hot, dry months?

Thanks in advance for your opinions.

 

[Urban Forester]

No its not too late. As long as the trees are not drought stressed the product will move.

 

[TominKY]

Thanks for the reply. So, would it still be best to wait until after a good rain?

 

[ATH]

First, I find it very rare where it makes sense to treat 12 ash trees on one property. Evlauate which trees are really worth keeping. Are all in good shape even without EAB? Are there some grouped together where you can treat 2-3 and remove another 2-3 out of the group without missing them?

As for the treatments:
*You do not want to treat a drought stressed tree. The label actually cautions it can injur the tree. So, I would wait for more than one good rain if you are as dry as we are. You can water, water, water if you really want to treat now.

*As you seek bids, ask how much product they are using. On the Tree-Age label (or most any insecticide label for that matter), there are variable rates on the label, and the applicator can 'pick' which rate to use. So if one person is using 5ml per inch, their chemical cost is 1/3 of the guy who is using 15ml per inch...and the Tree-Age costs $580 per liter, so that is a big difference. Based on what a few reasearchers have reported, I am using 5ml per inch on smaller trees and 10ml on trees over 15" dbh. I don't think 15ml per inch is necessary....unless you want to treat every 3 years instead of every other year that may make a difference.

*As EAB pressure increases, it may be worth treating individual trees with both imidacloprid and Tree-Age.

*Finally, note on the label for imidacloprid, you cannot apply more than 0.4 pounds of active ingredient per acre. At the maximum rate that is about 128 total inches of diameter...so you probably cannot even legally treat all 12 trees unless they are spread over an area greater than 1 acre or they are all relatively small trees.

 

[TominKY]

ATH, thanks for the detailed response. The property is actually over an acre, and there are a lot more ash trees on the property. I have resigned myself to the fact that I will be losing most of them. Yes, I have a few higher value trees that I am going to place the most emphasis on saving. I will treat a few of the smaller ones with the Imadacloprin to see if they make it. It is a lot less expensive than the Emamactin Benzoate. That stuff must have gold in it. Kind of ironic that the company that makes the stuff is in China. One of the arborists I talked to mentioned that the patent for the stuff is set to expire next year, and is hoping that a generic version at a much lower cost will become available. We can only hope! Between the EAB, ALB, and other pests, I really worry about what kind of landscape my daughters will be looking at when they are adults raising their own kids. It's really sad when you think about it. The whole thing is a product of our own greed.

Interesting that you noted the dosage. I saw that on the label as well - it doesn't exactly narrow it down. I would prefer to make this a 2 year and preferably 3 year affair - cheaper in the long run and less stress on the tree.

I do have some stem girdling roots on one tree that I am going to have to evaluate. One arborist mentioned that they have an "air spade" or something like that which would allow them to remove some soil from the roots at the base of the tree and evaluate this. Tough call on that one, as it is probably the nicest tree on my lot. It's always in the back of my mind that I could spend all this money treating the trees only to see them knocked down by a wind storm or an ice storm in the years ahead. I bought this place because of all the nice shade trees. This whole thing pretty much sucks.

 

[ATH]

Good to hear that you have really thought things through. People reacting on impulse are often not happy at the end of the day.

Couple of more thoughts:
1) Regarding the fear of wind, ice, etc... If we act that way in everything, we should just spend life cowered in a corner of the basement.
2) On the nice tree with stem girlding root: If you are going to invest in EAB treatment, it only makes sense to make sure the roots/trunk are functioning well, so I'd say have the girdling roots fixed.