Sometime after four am I woke up and left the tent. Stepping into the beams of the full moon, I walked to the shore of Polliwog Pond. Dawn was just breaking above an old hemlock stand, mist swirled above still water, and the loons began to call their old, melancholic song. In those few moments in the light of the moon and the dawn and sound of the loons I was transported to an ancient place.
The day before, I had walked from the site where I was camped with colleagues and friends on a week-long Leave No Trace course, to an an old growth forest on a height of land. Most of the trees there, and at our campsite on the shore below, were hemlock.
During the past year I have had a growing anxiety. After attending a Citizen Science Forest Pest Monitoring workshop in Allegany State Park with New York State Office of Parks (OPRHP) Invasive Species Control Field Director Robert O’Brien, who explained the threat of Hemlock Woolly Adelgid (HWA) (Adelges tsugae) to Eastern Hemlock (Tsuga canadensis), I began to realize the impact that the loss of hemlocks, a foundation species, would have on the Adirondacks. Here, especially in areas like Lake George, Keene Valley, and in much of the Lake Champlain Basin (including its far edge in the Saranac Lake Wild Forest and the St Regis Canoe Area) hemlocks are very dense.
Foundation species are critical species in the habitats they help create. In the case of hemlocks they moderate stream water temperatures for trout and other animals, provide a buffer for nutrient inputs to maintain water quality, stabilize shallow soils especially in steep gorges, provide shelter for animals and plants which is especially important in winter, provide critical habitat for migrating neotropical birds, and provide acidic substrate for lichens.
Anyone who has hiked, paddled, or driven through the Adirondack Park should realize what we could lose. If we do not act quickly, we are likely to lose the species.
We only need look to places such as the Great Smoky Mountains for an example of the devastation in store for the Adirondacks. Closer to home, decline of hemlocks is already well underway in the Catskills. HWA has been advancing quickly through New York State, and now is at the doorstep of the Adirondack Park (and is likely already present).
You can help prevent the loss of hemlocks in the Adirondack Park
• Become a Backcountry Forest Monitor. RSVP for an August 29th 10am to 4pm Workshop in Lake George.
• Attend a presentation by Cornell’s Mark Whitmore: The Hemlock Woolly Adelgid. A Formidable Pest We CAN Manage. The presentation will be held at the the High Peaks Information Center at 8pm on August 29.
• Sign-up for the Backcountry Forest Monitors Project to stay informed about upcoming outings and trainings.
• Sign-up to partner with the Adirondack Park Invasive Plant Program (APIPP)
What happens when HWA is discovered?
Last year Cornell University’s Mark Whitmore and the Department of Conservation (DEC) and Cornell University conducted a model early detection response to HWA in the Zoar Valley, treating almost 600 hemlocks to help them resist HWA until biological controls can be successfully introduced. OPRHP has conducted a smaller scale, but similar response in the Allegany State Park.
If we do not act, we are looking at a complete change to the face of the Adirondacks with resulting impacts to environment and economy that would come from such wide-spread habitat destruction and change. The time to act was yesterday, but if we act now, there is still hope to save hemlock stands in the Adirondack Park.
• HWA in the Adirondacks:
A Threat to Hemlocks
Flies Could Avert Hemlock Threat in New York
Watch For Hemlock Woolly Adelgid
• Hemlock decline in the Catskills
• Loss of foundation species in forests
• Discovery of HWA in Allegany
• Zoar Valley Response Model
• Changes to the hydrologic cycle in forests with the loss of hemlocks
Loss of Eastern Hemlock will Affect Forest Water Use
The Successors of Giants
Photo courtesy Mark Wright.
A version of the post was first published at Today @ADK.
The topic is timely and very urgent.
I highly recommend reading “Hemlock: A Forest Giant on the Edge” edited by David R. Foster (Yale University Press) ISBN# 0-300-17938-3. Scholarly and detailed, the book is still highly readable, with evocative personal style that quickly engages the reader. personal narratives surround and interpret the science. The Hemlock and its current adversary, the woolly adelgid, are each discussed in terms of physical stature, range and requirements, teleological drive, and the long sweep of “deep time’. The theme is developed with ample doses of humor, irony and endearing humility. (“Modeling causes us to formalize what we think we have learned from fieldwork”. -p. 154).
These biological control methods don’t appear to require much testing or other regulatory approvals. It looks like you can just release these non-native insects (apparently we have silver flies but not ones that prey on HWA so these are different) and just hope that it works and you don’t throw something else out of balance. I think we should do everything we can to stop it but we do need to be careful.
Is there any resistance in the Hemlocks to the insects?
Thanks for this post. It is quite accurate. The acid rain problem killed lots of spruce but is was mostly at higher elevations and not especially visible. The passing of giant old hemlock forests will be different, closer, feel more tragic because these huge trees appeared so permanent, and they will probably all die.
I don’t believe our region has yet to get a sense of what climate change is going to bring. The woolly adelgid may be our canary in the coal mine that gets people’s attention.
Jim and I have run a couple of workshops now about what an Adirondack response to climate change might look like. The most recent was at the July Common Ground Alliance Forum. The summary report is here: https://adkfutures.files.wordpress.com/2015/08/summary-of-climate-change-working-group-cga-2015-w-full-text-scenarios.pdf
Work in our region led to a solution to the acid rain problem, and we are seeing a real recovery. We could figure out the source of the emissions and address the problem. Climate change is way harder. The problem is, well, all of us, all over the planet. Unlike being able to identify point sources to address, as we did for acid rain, we have to come to see that we all need to make personal changes. BTW, New York is a leading state on this front, but we probably can’t save the hemlocks.
Thanks, again, for this post.
There is little to no resistance in eastern hemlocks to HWA. The success of HWA is partly the result of climate change (if you include unpredictable weather and severely cold winters as part of the change), but more to do with the way it is currently reproducing. In its native environment HWA reproduces sexually. Here the host spruce species for that stage in the life cycle of HWA is missing so the insect reproduces asexually only. This reproduction strategy makes it much easier for the species to adapt to cold climates. Since cold tolerance is genetically linked, even one insect surviving an extremely cold winter can reproduce very rapidly and the resulting generation will likely be cold adapted. You can read more about this at the link below. See Mark Whitmore’s article on the effect of cold temperatures on invasive species: http://www.dec.ny.gov/animals/7250.html
Thanks Cathy – Mark’s article was interesting.
It seems the HWA does have a way to survive through cold winters, although the cold may slow their advance and warmth will hasten it. But warm or cold, it is still approaching. Perhaps it is already here but not noticed yet. This makes me think of dutch elm disease and its impact in the 1970s, but I think this will be a bigger deal in our landscape.
The same article mentioned Emerald Ash Borer, but there isn’t enough research to know if it can do alright though very cold winters. Apparently it does like warmer climes. However, I don’t think ash is as common as hemlock in our forests. No one writes about ‘stately stands of ancient ash trees’. I believe ash mostly grows in mixed hardwood forests so it won’t be quite as notable as the hemlock die off.