Hemlock woolly adelgid

pcray1231

pcray1231

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Lebanon, PA
This is something that surprisingly (and somewhat embarrassingly), I just heard about. Seems the eastern Hemlocks are dying, like nearly 100% of them in the widespread infected areas, and the infected areas are spreading northwestward.

It's a type of invasive, non-native aphid. There are fears that the hemlocks will go the way of the American Chestnut tree.

There are some chemical treatment methods that have been shown effective. But there are concerns with widespread spraying with the effect of the chemicals on ecosystems, especially trout streams. Right now they are essentially treating a small amount of individual trees in parks and such, but its a drop in the bucket compared to all the trees in the deeper forests, which are of course of more interest to us as trout fishermen. There are experimentations on biological control, basically introducing predatory beetles and such, which could bring its own issues.

Hemlock's are vitally important for wild trout, especially brook trout in the headwaters. Studies have shown a strong correlation with wild brook trout populations and a hemlock tree cover, and the hemlocks are/were still in a state of recovery after the logging days.

Anyone have any personal stories, involvement in control efforts, or otherwise thoughts? As I said I'm still in the stage of learning about the issue. I'd consider getting involved if there's something that can be done.
 
It's been here since before you or I were born. At least from the jist of this article, it seems it weakens trees more than it kills them.

http://www.dcnr.state.pa.us/forestry/woollyadelgid/index.aspx

I'd be very wary of introducing something that may in the long run be worse than this.

Boyer
 
They also have a "what can I do" link. I have a Hemlock in my yard, so I will try to follow these guidelines to help prevent the spread.

http://www.dcnr.state.pa.us/forestry/woollyadelgid/whatcanido.aspx

Boyer
 
It is really simple to take care of. All you need to do is mix some dishwashing soap with water and spray your hemlocks. We have been mixing this combo up in our weed sprayer and doing all the hemlocks at home and camp and it has been working really well.
 
I was thinking more on a mass scale, rather than the tree or two in a backyard. Like, is there anything you can do for an entire valley covered in Hemlocks? I assume this would involve helicopters and such, but they probably need money.
 
The HWA is a big concern down in Maryland as well although there remains some difference of opinion regarding how widespread it is, and different prognostications regarding future severity. HWA has been documented in MD in, among other areas, Savage River State Forest and Cunningham Falls SP (both of which lay close to PA on terrain features that extend into our state). There have been some limited introduction of predatory beeltes in western MD (the beetles cost $2 ea) but I don't know whether solid conclusions can be drawn yet.
 
I noticed many struggling Hemlocks up on and around Penn's Creek. Can't help but think this could be a problem in marginal water. On a personal note, a few of my Hemlocks in my screen planting here in Hershey have been struggling. I figured Wooly but my arborist said no. I had them sprayed with a soap solution which said works fine though I am not sure if he meant to protect from the current problem or to protect against future Wooly attacks. He said you would see a white residue which I didn't have, but I noticed a few days later it was all over my neighbors trees. Probably only a matter of time.

My cousin's husband in Oley had his attacked and he got some strong mix of a pesticide from a golf course superintendent he knows that can't be obtained by consumers. This took care of his problem. I didn't know there were different rules for Golf Courses. Got to wonder though about runoff from those treated areas. We grew up organic before it was cool, so I would let my trees die before I would initiate that kind of a regimen. It is a shame since I think it is the state tree.

Jay P
 
Two instances; my mother had it infect her hemlocks in her yard in central Pa. The local garden shop treated it and appears to be gone. On the larger scale front it's starting to show up on my woodland which adjoins Bald Eagle State Forest. I'm considering lumbering off the hemlocks while the wood still has value.
 
The adelgids have been bad in NJ. NJ is at the edge of hemlocks natural range and it seems to hit the trees in the warmer areas at the end of their range worst. Towards the warm end of the range they grew mostly in ravines and those groves are totally gone in some places. In the cooler areas in the far Northwest corner of the state that are more hemlock friendly they are doing better.

Dish soap/insecticidal soap works by clogging the breathing pores. It works best at the right time in the spring before they weave those wooly protective coverings. Timing is a lot with controlling scale insects.
 
Cold winters affect the populations of HWA adversly, so we should hope for a couple of volcano eruptions in remote areas, to give us some extra cold winters.
I think and this is my own opinion, that several generations offorest fire suppression has aggravated all these invasive species of bugs. One thing everyone can dois stop transporting firewood, or only transport what you will use over the time of your stay. The emerald ash borer has been transported from Michigan to PA in about 12 years, and threatens to kill every ash treein the country. Then we will be see the use of stupid metal bats at major league baseball games.
 
Personally, I don't think fire suppression has much to do with invasive speecies it is foreign trade and unchecked cargo, specifically from Asia. Before anyone asks I work in forestry and attend trainings and meetings on this on a regular basis so i am qualified to make that remark. As for the affects of HWA, I travel to western North Carolina regularly and have seen the affects of HWA, it is widespread mortality of hemlocks which we should all know are vitally important to trout streams, especially freestoners. There has also been research showing relationships between caddis species and hemlocks.
I do not think that there is presently any feasible way for dealing with the affects of HWA on a larger scale such as in the north central region of the state. I helped do treatments in the southern part of the state a couple of years back and it sucked long extremely hard days working on your knees to apply the chemical. And this only treated small areas. Franklin, while i am not against cutting your hemlocks, they have very little value, one of the lowest value trees in Pa, so think if it is really worth cutting them or not.
Lastly, Chaz is 100 percent right about not transporting firewood, I am a pessimist and believe it is too late for Ash, it has been found in several counties in Pa and NY now and will continue to spread. That being said every time we transport firewood from one area to another we risk spreading something new. To the best of my knowledge HWA has been found in two spots in Potter County in the last year Ole BUll state park and Sinnemahoning, guess how it got here.
 
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