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> Health EH Hydrilla in Cayuga Lake

Hydrilla in Cayuga Lake


Quick Facts  |  Monitoring data 2012-2018


Photo showing a cluster of Hydrilla plants(August 2018) – Hydrilla, an extremely aggressive aquatic plant, was found in Ithaca in early August 2011. National experts on Hydrilla and local resource managers/stewards agree that an approach including the use of herbicides is the best method to achieve eradication of Hydrilla.

Total eradication is a long-term process; however the treatment over the past seven years has been very successful, resulting in a dramatic reduction in the number of rooted Hydrilla plants and ungerminated tubers now being observed.

Tompkins County has previously addressed Hydrilla through hand-removal, benthic barriers, and by applying herbicide (both Endothall and Fluridone) in Cayuga Lake under permit from the NYSDEC. (Yearly monitoring data from this initiative can be found below.) This summer, Komeen Crystal will be used to target this invasive species. Komeen has been previously used as an herbicide in Cayuga Lake to control patches of Hydrilla near Aurora.

Komeen Crystal is granular chelated copper herbicide that will be applied below the water surface at a rate of 1.0 part per million (ppm). Copper is a metal that naturally occurs in the environment and low levels present no threat to human health. There will be no restrictions on fishing and swimming during this application process. The Tompkins County Health Department will continue monitoring the health of Cayuga Lake and regularly post results online.

Questions can be directed to the Environmental Health Division at (607) 274-6688.

Botanical line drawing of a single Hydrilla plantQuick Facts:

  • Hydrilla can grow up to 30 feet long and form thick mats
  • The dense vegetation can harm boating, fishing, and swimming in Cayuga Lake
  • Hydrilla reduces oxygen in the water- impacting native fish and plants
  • It is known as one of the “Most Invasive Species in the World”
  • Hydrilla is native to Asia

What You Can Do:

  • Never dispose of aquarium plants in bodies of water
  • Remove plant matter from boats and other equipment before and after entering the lake
  • Clean, dry, and inspect boats and equipment before moving to other bodies of water
  • Identify and report sightings of Hydrilla in Cayuga Lake

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2018 Monitoring Results and Information »


2017 Monitoring Results and Information »


2016 Monitoring Results and Information »


2015 Monitoring Results and Information »


2014 Monitoring Results and Information »


2012–2013 Monitoring Results and Information »