Crooked River Farm has several patches of the dreaded Ailanthus tree, also known as Paradise Tree, Tree of Heaven, or locally called Shumace.
Ailanthus is one of the most dangerous trees in VA. Where it sprouts up, it sets out it’s own natural herbicide that keeps anything else much from coming up except itself. Female trees set tens of thousands of seeds each year, and it readily sprouts from its roots. Cut down an Ailanthus, and you’ll have hundreds of new trees sprout from the roots. So it needs special treatment to eradicate. It now lines our roadways all over VA as well as the edges of forests. VA Tech researchers have been working on biological control agents for several years to no avail.
There are no organic control/eradication techniques for Ailanthus, so here we parted from our organic approach and resorted to limited use of herbicide.
The common recommendation for Ailanthus eradication is to spray the leaves with herbicide. This of course is a bad idea, as there is no way to prevent the herbicide from drifting onto other plants. A common technique of killing undesirable trees and shrubs is to cut off the plant, and paint the stump with herbicide, but Ailanthus foils this technique by immediately sending up sprouts from the roots that don’t die after the host is killed.
So we tried a different technique. What we did was hack into the bark of the trunk with a machete (a hatchet will do) around the tree to expose the cambium layer and create a pocket for the herbicide. If you girdle the tree completely it will sprout from the roots and you’ll create a bigger problem, so the trick is to leave about 1″ of intact bark and cambium in between the hacks. Generally, you do one hack for every inch of tree diameter. And then in each hack, you squirt the herbicide to the point just before it will spill out of the hack. For sprouts less than 1″ in diameter, we’ve had 100% success with just exposing the cambium with a scrape and then squirting the scrape. The Ailanthus thinks it’s still alive while it absorbs the herbicide, and by the time it realizes it’s dying and tries to send up root sprouts, it’s too late.
This must be done while the tree is actively growing or it won’t work. This means from the time of first leaf-set up until the females are flowering. We “treated” trees after flowering, and they seemed to respond much more slowly and will have to wait until spring to see if they have been killed or not.
We just bought a very small hand-held spray/mister bottle at the local garden shop and used Triclopyr herbicide, sold under various brand names. We did not dilute the Triclopyr.
Ailanthus Patch
Ailanthus patch after poison and BullHog
So far at least, it appears to work. The larger the tree, the longer it takes for it to die. One-inch trees will be bare of leaves in 4-6 weeks, 3-4 inch trees seem to take 8 weeks or so, and larger trees even longer.
And the work is fast – with a machete in one hand and the squirt bottle in the left, you can kill one of these nasty buggers in well under a minute. Just this summer, Trish and I killed acres of this “Tree from Hell” and just have some clean-up work to do in the 2009 growing season.
Dying Ailanthus
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March 5, 2009 at 11:09 pm
Jeff
I think you are over-doing it by not diluting the triclopyr. I used it some years ago to kill invasive exotics on my property and found that 10% worked fine on most everything. There were two species that required 20%, though. Also, be very, very careful with this herbicide – it can be absorbed through the skin and causes dizziness and nausea if that happens. Also, because it is mixed with an aromatic petroleum distillate (Penevator), you can breathe the fumes, to a most detrimental effect. I would urge the applicator to wear a respirator when using this very toxic herbicide. It is also not necessary to cut into the cambium – the Penevator will carry it into the tissue. Just spray it at the base of the trunk and then wait for the tree to die.
March 6, 2009 at 5:18 am
Crooked River
Jeff – thank you so much for posting. You bring up some very interesting and valuable points for those dealing with “Tree from Hell”, and herbicides both in general and specific.
I don’t think I was overdoing it by using it undiluted – the product I was using was already diluted. And I’m lazy by trade (engineer)
I should have been more specific when saying Trichlopyr, as it comes in many different formulations. Some (not the product I was using) are specifically formulated for basal bark applications, the technique you describe. The basal bark application is said to work well on smaller trees at certain times of year (with the proper formulation, which it sounds like you had). I don’t like spraying due to the collateral damage, and I chose the cut and squirt technique also because it was what seemed to work best in the summer, when I was at it. But your approach is perfectly valid on Ailanthus from what I’ve read, and thanks for sharing. And major kudos to you for working on getting rid of your invasive exotics.
And I hate using herbicides at all – but it is clearly the only way of dealing with Ailanthus. Although we were not spraying, and had no direct contact with the herbicide, we did use rubber gloves and (sometimes) respirators when applying. And, like you, I encourage anyone dealing with herbicides to know just what you are dealing with and take extraordinary precautions.
Although just a starting point, here is the best web page I found on getting started on the various means of Ailanthus eradication:
http://www.nps.gov/plants/alien/fact/aial1.htm
Again, thanks for sharing, and bringing up some good points, Jeff. What started out as just an experiment to see what this blogging thing was all about and share what we were doing with family and a couple of close friends has turned into something that gets dozen of hits per day, many with the search term “ailanthus eradication”, “multiflora rose”, “forest restoration”, “pasture restoration”. So would love to see more discussion of some of the topics here that aren’t really discussed effectively much elsewhere.
October 28, 2009 at 12:28 am
Alan
I want to add my thanks for this blog and the information sharing. Specifically the information on Ailanthus eradication. I work on projects here in California where the tree has become a real problem. We have had the problems you have describe with re-sprouting and doing so quickly after one is cut down.
I will try the methods you have described and let you know how it goes!
March 6, 2009 at 1:07 pm
Jeff
Chris – and I should have been more specific in regards to the product that I used. It was Garlon-4 and you are correct – it is formulated to be used as a basal bark application mixed with Penevator. Down here in Florida, Garlon-4 works well at any time of the year, but I would imagine that it should only be used during the growing season in Virginia. I purchased pure Garlon-4 from an agricultural chemical supply house and mixed it at a 10% rate with Penevator, which is colored red and is similar to a light machine oil. There are diluted solutions of Triclopyr available on the market (Pathfinder being one of them), but since I had a large number of trees to kill, I elected to go with the undiluted product, as using the diluted solution is rather expensive. I believe Pathfinder is a 10% dilution of Triclopyr and there are probably other brand names available also.
One other tip: RoundUp Pro mixed at a 10% strength will kill a lot of brushy species and even some trees. I had a very prolific vine (Gold Coast Jasmine) that I cut down to about 2′ high with a commercial hedge trimmer and then waited until there was a flush of new growth. Then, I sprayed the 10% RoundUp Pro solution on the new growth and that was the end of those plants! I imagine such a strategy would work on multiflora rose also, but I haven’t had the opportunity to try it out yet. I wouldn’t use a hedge trimmer on multiflora rose, though – I’d let John come in and knock it down with his Bull Hog first. Cutting the plant down and waiting for the flush of new growth avoids the problem of overspray which endangers other plants in the area.
I don’t like to use herbicides either, but in some cases, spraying really is the only practical solution available. All herbicides must be used carefully and wisely by an experienced applicator.
October 28, 2009 at 12:54 am
Crooked River
Thought I should give an update on the Ailanthus eradication program as there are people who hit this page daily searching for information on Ailanthus eradication.
This spring, many, if not most, of the larger (8″ or larger in diameter) Ailanthus were severely distressed (but not completely killed) by the hack-and-squirt treatment in the fall. So I went with the basal bark treatment on them. I bought Garlon, and diluted it 5:1 with diesel fuel. I sprayed it liberally around the bottom 18″ or so of those trees, and within a month there wasn’t a leaf hanging on any of them. I’m still going to wait until next spring to cut them down, though, to make *sure* they’re dead!
This spring there were a few patches where the Ailanthus sprung up as thick as a carpet. This was where others had cut down trees the previous spring not knowing what they were. With these, I took a small squirt bottle with a 10% solution of triclopyr and spot sprayed each and every little one. They came up in about 3 cycles before giving up the ghost for good.
We’ve gone from about a thousand of these trees to now just two small patches of about 100 or so total, which I’ll get next year. Some, of course, will continue to sprout up from seeds, so I’ll have to keep an eye out, but the problem is just about licked, methinks.