NYSDEC Treatment of Hydrilla in the Croton River

What is Hydrilla?
Hydrilla verticillata is a freshwater plant with stems that can grow up to 25 feet long. The plant branches out horizontally at the water's surface and creates dense mats. Hydrilla has small, pointed, serrated leaves arranged around the stem, typically in whorls of five. Hydrilla grows quickly and creates dense mats that can block out sunlight and harm native plants, and its density can also kill fish by decreasing oxygen levels.

Hydrilla is native to Australia, Asia and Africa and is believed to have made its way to the U.S. as an aquarium plant.

Hydrilla is often spread by boaters, as hydrilla fragments can cling to boats and trailers. Very small fragments of hydrilla can start new populations.

July 17, 2020Status Report
July 3, 2020Status Report
June 19, 2020Status Report
June 5, 2020Status Report
April 2020NYS DEC Notice
October 18, 2019Status Report
October 4, 2019Status Report
September 20, 2019Status Report
September 6, 2019Status Report
August 23, 2019Status Report
August 9, 2019Status Report
August 1, 2019Plant Condition Photos
July 26, 2019Status Report
July 12, 2019Status Report
June 28, 2019Status Report
June 15, 2019Status Report
May 23, 2019Treatment Notification
April 8, 20192018 Annual Update
November 30, 2018Five-Year Management Plan
November 16, 2018Status Report
November 2, 2018Status Report
October 19, 2018Status Report
October 5, 2018Status Report

September 21, 2018

Status Report

September 13, 2018

Treatment Notification

August 24, 2018

Status Report
August 10, 2018Status Report
July 27, 2018Status Report
July 13, 2018Status Report
June 29, 2018Status Report
June 15, 2018Status Report
May 2018NYS DEC Resuming Treatment of Hydrilla
April 2018NYS DEC Notice
February 2018NYS DEC Letter Re: Wetlands Permit
March 2017Resolution to Approve Chazen Proposal
March 2017Memo from Water Control Commission
February 2017Chazen Companies Proposal - Review of NYSDEC Wetlands Permit
January 2017Letter from Water Control Commission & Waterfront Advisory Committee
May 2016 NotificationNYSDEC
 Hydrilla PowerPoint Presentation
 Information from DEC Website