Invasive Aphid Threatens Finger Lakes Hemlocks — and the Watershed

Jim McGinnis — Seneca Lake Pure Waters Association
Paul Szmal 9:03
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The official logo for the Seneca Lake Pure Waters Association, an organization dedicated to protecting the Finger Lakes region.
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An invasive, needle-killing aphid is spreading through the Finger Lakes region, and the Seneca Lake Pure Waters Association is launching a volunteer-driven effort to find and protect hemlock trees before it’s too late.

Jim McGinnis, project manager for the Hemlock Initiative at the Seneca Lake Pure Waters Association, joined FLX Morning on February 7 to explain the growing threat posed by the hemlock woolly adelgid — a tiny aphid that attacks and kills hemlock trees by feeding on their needles. If you’ve noticed hemlocks losing needles and drying out, McGinnis says, that’s the adelgid at work.

Hemlocks are particularly vital to the Finger Lakes watershed. They grow along the steep walls of ravines, shading streams, protecting wildlife habitat, and filtering runoff that flows into Seneca Lake. McGinnis warns that if the die-off continues unchecked — as it already has in much of Pennsylvania — invasive or less ecologically beneficial species will move in to replace them.

The good news: there’s a proven treatment. New York State Parks has spent roughly a decade applying a targeted insecticide to hemlock bark at locations like Watkins Glen State Park. The chemical is absorbed by the tree’s sap and carried to the leaves, where it kills the adelgid without significant environmental dispersal. Biological controls — specific beetles and flies that are natural predators of the adelgid — are also being released in partnership with the New York State Hemlock Initiative at Cornell University.

The Seneca Lake Pure Waters Association is now in the survey phase, using geographic information system (GIS) technology to map hemlock locations around the southern end of Seneca Lake — from Lodi south on both sides. Volunteers are being trained this month to go into the field and document tree locations, particularly on private land, so the group can identify the most critical trees and apply for U.S. Forest Service funding to treat them.

Anyone interested in volunteering — or in supporting the association’s broader work on invasive species, water quality, lake levels, and harmful algal bloom monitoring — can visit senecalake.org/volunteer. To sign up for the Lake Watch newsletter, go to senecalake.org/lakewatch. The association is also active on Facebook, Instagram, and YouTube.

Read Full Transcript

Paul Szmal: It's 8.15 on FLX Morning on Finger Lakes News Radio, I'd like to welcome in Jim McGinnis from the Seneca Lake Pure Waters Association, he is the project manager for what is called the Hemlock Initiative. Jim, good morning, how are you this morning?

Jim McGinnis: I'm great, how are you this morning Paul?

Paul Szmal: Doing great, doing great.

So what is the Hemlock Initiative?

Jim McGinnis: Well in the Finger Lakes area, a foundational, a fundamental tree is the hemlock and it's being killed by an aphid called the Hemlock Woolly Adelgid. If you see hemlocks that are losing their needles and drying out, they're being attacked by the Hemlock Woolly Adelgid.

Paul Szmal: And why start that initiative now? Is it getting to be a critical condition for these hemlocks?

Jim McGinnis: Yes, absolutely. In fact, the New York State has a Hemlock Initiative that's been going on for many years and we in the Finger Lakes are now starting to see an increase in this die-off of the hemlock trees. The hemlocks are critical to our watershed and so that's how the Pure Waters group got involved is that we're trying to protect our watershed and these hemlocks are critical to that.

Paul Szmal: And how so? How do they help out the ecosystem?

Jim McGinnis: Well the hemlocks are growing on the sides of our ravines and they're able to grow there and provide shade to streams and to protect the wildlife in the area. They also prevent runoff into the lake and so that's why they're critical to us.

Paul Szmal: So as a part of this Hemlock Initiative, what are some of the steps that are being taken?

Jim McGinnis: Some of the things that we're doing is to provide awareness to people that this is happening and the New York State Parks Department for many years, about the last 10 years, has been treating the trees and they can treat them with an insecticide in a very prescribed manner that doesn't have much dispersal. The trees are soaked in the bark with the insecticide that goes into the tree and the tree draws that up with its sap and that goes to the leaves where the hemlock woolly adelgid is feeding and so that's what can kill that hemlock woolly adelgid.

What we are doing now is surveying the area with a geographical information system to find out where the hemlocks are located and we can do that by comparing photographs of the area with the leaves on the trees and the leaves off the trees. So the leaves off the trees, we can see where the conifers are and particularly where the hemlocks are. So once we found those areas, we're going to go and survey those and separate out from white pines, spruces and find out where the hemlocks are and then work with the private landowners to identify the tree, the tree locations, the critical ones that are protecting our watershed and then we're going to apply for funding to the Forest Service to get funding for the insecticide to protect and kill those hemlock woolly adelgid.

Paul Szmal: We're talking with James McGinnis who is the Hemlock Initiative Project Manager from Seneca Lakes Pure Waters Association. If you weren't making this effort, Jim, what would be the worst case scenario that might happen?

Jim McGinnis: Well, the hemlocks are going to die off and those hemlocks down in Pennsylvania have already had a severe die off and so once they do, then they're going to be replaced by other invasive species or other species that don't provide the same kind of benefit to the watershed.

Paul Szmal: And you mentioned the, forgive me if I'm pronouncing this wrong, is it the adelgid or the adelgid is the insect that's the main public enemy number one, shall we say, for the hemlocks?

Jim McGinnis: Yeah, adelgid. It's the public enemy number one, as you say.

Paul Szmal: I imagine that a project like this is a pretty massive undertaking. It sounds like there's a lot of steps. How many people does it take to accomplish this sort of thing?

Jim McGinnis: Well, we are just in the phase of doing the surveying and so that's going to take a group of volunteers and we are training those volunteers this month and they'll be going out to document the location. So you can just imagine the area that can be covered around the bottom end of Seneca Lake. We're going to be looking in detail from Lodi south on both sides of the lake and we're going to be covering all the private landowners. So it's going to be a large volunteer lift for us to go and find those and we'll be doing it in this winter season.

Paul Szmal: Ah, okay. I should mention at this point that there is a successful model for saving of hemlocks and chances are you may have already seen the work that has been done if you've been to the Watkins Glen State Park.

Jim McGinnis: Absolutely. Yeah. In fact, I walk to Glen regularly and you can see the effects of the insecticide and also which I haven't mentioned before, there are bio controls. So there are beetles and silver flies which are predators to the hemlock woolly adelgid and that's the really the natural case. That's the case on the west coast of the United States is those the beetles and the silver flies are able to manage the hemlock woolly adelgid and they aren't seeing this die off that we see here on the east coast. So we're working with the New York State Hemlock Initiative in Cornell to support their release of bio controls.

Paul Szmal: Sorry, just having a little technical difficulty there, Jim. My apologies. So if you're looking for volunteers and somebody wants to be a part of the program here to help save the hemlocks, how do they go about getting in contact with you?

Jim McGinnis: Yeah, very simply. They can just go on SenecaLake.org, it's a great website and they can also find opportunities under SenecaLake.org slash volunteer and go right on that website and we'll be contacting and following up and really look at the interests of volunteers, whether it's from finance to membership, administrative activity, but also a real focus on invasive species, water quality, lake level, and we have pretty well known for HABS monitoring and communicating to people about the dangers of the harmful algal blooms.

Paul Szmal: I should also mention too that if you want to keep updated on the items that the Seneca Lake Pure Waters Association are working on, not just the hemlocks, but a load of other things that they take care of and work on during the course of the year, that you can sign up for the newsletter.

Jim McGinnis: Yeah, absolutely. Thanks for mentioning that, Paul. That's great. Yeah. By the way, the web address for that is SenecaLake.org slash LakeWatch and you can also follow along on social media, Facebook, Instagram, and YouTube.

Paul Szmal: Jim, thank you so much for filling us in and I hope that this turns out to be a very successful venture much the way things have gone at Watkins Glen State Park. Thanks very much.