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Cornell University

New York State Hemlock Initiative

Keeping the legacy alive

HWA on the Water

Our Skaneateles Lake HWA boat survey

Yesterday we boarded a boat on Skaneateles Lake to look for hemlock woolly adelgid. Usually, we’re traipsing through the woods and along streams when searching for HWA, but you can also see HWA damage from the water. When boating or paddling, you should look out for pale, greyish hemlock foliage or hemlocks with advanced needle loss to detect HWA on shoreline hemlocks. Late spring into early- and mid-summer is a great time of year to use this survey method because hemlocks should have bright, new, lime-green buds, and the pale, greyish hue of infested trees really stands out. If you see lots of pale foliage and few to no new buds, it’s a good sign that there is HWA. If you see these signs, move in closer to shore for a better look (and don’t forget to report your findings)!

On the left, you can see a hemlock branch with really bright, new green buds. The hemlock branches on the right are looking pale, greyish, and sickly. Infestations of HWA prevent new hemlock growth, and hemlock branches with a pale, grey cast can be easily seen from the water.

Can you see the infested hemlocks? In some cases, you’ll see just a branch or two looking pale and grey. As the infrestation advances, more and more of the canopy will take on this unhealthy hue. When you see a hemlock looking like this, it is important to get a little closer to check for HWA.

HWA was detected during our search on the southwest shore of Skaneateles Lake. We knew that HWA would be here, and we collected a few samples to bring back to the lab to examine. We are hoping to find evidence of our 2015 silver fly biocontrol release.

We were joined by members of NYS Dept. of Environmental Conservation and Capital-Mohawk PRISM. In addition to surveying for HWA and assessing the efficacy of boat surveying as a useful early detection method, we were also collecting foliage from a previous year’s biocontrol release to see if there is evidence of silver flies in the area. That release, done in 2015 along the southwest shore of Skaneateles Lake, was the first wild release of silver flies on the East Coast.

Many thanks to our partners for joining us, and to our boat captains for the day, Bob and Tracy Duckett. A fun and informative time was had by all!

Our boat crew for the day

Our skipper Bob Duckett and our adelgid expert Mark Whitmore enjoying a day on the lake

For more photos of our boat survey trip, you can check out the Facebook photo album from our trip.

Report HWA Findings

To tell us about hemlock woolly adelgid findings in your area, click here

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