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Invasive Species

Resources & links for managing invasive species

How to Report Invasive Species Using iMapInvasives:


Hemlock Woolly Adelgid:

The Hemlock Woolly Adelgid (HWA) is an invasive forest pest that is attacking our Eastern Hemlock Trees. It is an aphid-like insect pest that feeds on hemlock trees with a piercing-sucking mouthpart. Adelgids feed on hemlocks by inserting their straw-like mouthparts directly into the twig. During the fall and winter months, developing adelgids feed on young twig tissue, including starch reserves critical to the tree’s survival. The adelgid causes hemlock decline and mortality within 4-10 years of infestation in its northern range. HWA feeds throughout the fall, winter, and spring when the tree is actively transpiring. While HWA is actively feeding and developing, it begins to accumulate the wool that gives it its name.


The New York State Hemlock Initiative has a great website where you can learn more about the HWA and:

Click here to learn more about the HWA Hunters Program and MyHemlock Reporting Programs.

The Finger Lakes PRISM is another great organization with tons of information on HWA:

Click here for a Hemlock and HWA ID Guide.

Click here for an excellent HWA Brochure packed with information.

What You Can Do:

Use iMapInvasives to report HWA. This invasive species mapping tool is used by New York State Department of Environmental Conservation to plan management and prioritize HWA treatments in New York. Your contributions to the state invasives map improve our ability to conserve and protect hemlock resources. You can download the iMapInvasive app on your smartphone or tablet. can also submit HWA findings on the NYS Hemlock Initiative Website.

Interested in chemical treatment to stop HWA? Click here for the New York State Certified Pesticide Applicator list. The best time to treat the trees is the spring and fall during the tree’s most active time.

Recording of February 9, 2021 HWA Training:

spongy moth

Spongy Moth:

The spongy moth (Lymantria dispar) is a non-native insect from France. Its caterpillar (larva) stage eats the leaves of a large variety of trees such as oak, maple, apple, crabapple, aspen, willow, birch, mountain ash, pine, spruce, and more.

For more information, visit the NYS DEC website at:

For the recording of the fall 2020 webinar on surveying spongy moth egg masses in winter, click here.

Photo of Spongy Moth and eggs
Photo of Spongy Moth

Spotted Lanternfly:

Lycorma delicatula, or Spotted Lanternfly (SLF), is an invasive plant hopper from Asia. In the United States, it was first found in Pennsylvania in 2014. Spotted Lanternfly has been found in New York State on Staten Island, Port Jervis, Sloatsburg, Orangeburg, and Ithaca. SLF threatens the agriculture and forestry industries, and is also a nuisance pest. The nymphs and adults feed on over 70 different plants with piercing sucking mouthparts. To read more about the Spotted Lanternfly, go to:

Cornell's Integrated Pest Management website is another great resource:

If you think you have seen a spotted lanternfly, please report ASAP by clicking hereYou will need information about the location of the find, and ideally, photographs of the pest.

Click here for Cornell's IPM SLF Factsheet.

Click here for NYS DEC's SLF Factsheet.

Photo of Spotted Lanternfly
spotted lanternfly
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