Impacts

• Main Authors: Alison Fox, Hydrilla Verticillata, Threat To Biodiversity
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarc*; Antarctica
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.140.8833; http://www.pserie.psu.edu/seagrant/publications/fs/Hydrilla.pdf

Hydrilla verticillata is sometimes considered nature’s “perfect weed”. It grows and spreads at a very fast rate, covering the surface of water bodies it infests. In doing so, it can restrict boating, fishing, swimming, and other recreational uses. Native & Introduced Ranges Hydrilla is a federal noxious weed that continues to spread to new regions in the United States. It is unknown exactly where Hydrilla originated, but Asia, Africa, and Australia are all mentioned in the literature as native ranges. Hydrilla was introduced into the United States in the 1950s and became widespread in the southern states. In Pennsylvania, Hydrilla was first reported in the mid-1990s in Adams and Bradford counties. It is also established at several additional sites including the Schuylkill River in Philadelphia, Highland Lake in Bradford county, and Lake Nockamixon in Bucks county. Currently, Antarctica is the only continent without records of Hydrilla. Spread Hydrilla was imported to the United States as an aquarium plant. Subsequent releases, along with transport by recreational boaters, helped it spread across the United States. Hydrilla reproduces primarily vegetatively; even the smallest living plant fragment can float downstream and form a new plant. This makes it easy for whorls of Hydrilla stuck on boat motors, trailers, livewells or bait pails to start new infestations. Currently, Hydrilla is found in approximately 690 bodies of water within 190 drainages and 21 states.