Hydrilla

Identification

Hydrilla (Hydrilla verticallata) – Hydrilla's small leaves are strap-like and pointed. They grow in whorls of four to eight around the stem. The leaf margins are distinctly saw-toothed. Hydrilla often has one or more sharp teeth along the length of the leaf mid-rib.

Photo provided by the Center for Aquatic and Invasive Plants

Situation in Kansas

Hydrilla is Federal Noxious Weed and a quarantined Kansas weed under the Federal Noxious Weed Quarantine that was enacted in 2004. During fall 2008, Hydrilla was discovered by a Kansas Department of Wildlife and Parks district fisheries biologist in a ¾ acre park pond in Olathe, a suburb of Kansas City and subsequently confirmed by KDA.  We are unable to confirm the method of introduction but there is a high likelihood that discarded aquarium material lead to the establishment of hydrilla.  It has been concluded that hydrilla has been present from 2-4 years at the park pond and has not been detected downstream at of this report.  A management plan was developed with the goal of eradication with the cooperation with the City of Olathe, Kansas Department of Wildlife and Parks, and the Kansas Department of Agriculture.  Parts of the management plan includes: monitoring the current situation, surveying downstream, pond drawdown, and herbicide application.  At this point grass carp, are not a good option due to unfavorable water quality from street runoff.   Finally, the site will be monitored continuously for at least three years after the last known detection.

Hydrilla in a Kansas watergarden.