The Stony Brook-Millstone Watershed Association is asking area residents to keep a look out for an aggressive invasive aquatic plant - the water chestnut (Trapa natans). Not the edible plant of Chinese cuisine, this water chestnut is native to Europe and Asia and thrives in shallow, slow-moving water, growing and reproducing rapidly. It can quickly spread and take over a lake or stream, as has occurred at Baldwin Lake in Hopewell and Amwell Lake in West Amwell.
A water chestnut invasion suppresses native aquatic plants, dramatically affecting the natural food webs in the waterway. It physically clogs the water, encumbering birds and fish and causing them to have difficulty pursuing their prey. It also greatly impedes human recreation, including boating and fishing.
Water chestnut is readily identified by its circular cluster or rosette of leaves, each equipped with an air bladder along the stem. The small white blossoms of early July are now forming distinctive four-pointed seedpods, which can sink to the bottom of a waterway and lay dormant for significant periods of time. The floating plant is rooted to the soft sediments in the water through a branching root that can reach up to 5 meters, or up to 15 feet, in length. It can reproduce rapidly with one acre of water chestnut producing enough spiny seeds to cover 100 acres of water the following year.
An aggressive invasive plant, water chestnut is being targeted for removal because it is a relative newcomer to this area. It can be pulled by hand, slowly and carefully to remove the entire length of the root. The Watershed Association's own Conservation Team removed a few garbage bags full of water chestnut from Wargo Pond at the Watershed Reserve in Hopewell after it was spotted by Celia Dubin, a J. Seward Johnson Sr. Environmental Education Intern with the Watershed Association. The Watershed Association continues to monitor Wargo Pond and keep an eye out for other waterways in the Stony Brook-Millstone Watershed.
Area residents can help eliminate the spread of water chestnut by reporting sightings to the Rutgers University Water Chestnut Task force online at http://morris.njaes.rutgers.edu/ag with a simple form. Boaters should be certain to thoroughly wash any equipment and trailers after use to prevent spreading the plant to other bodies of water. Fishermen should be sure not to empty bait buckets into waterways after fishing as these may contain the tiny seeds of water chestnut. To learn more, check out the Watershed Association's video at thewatershed.org.
About the Watershed Association
The Stony Brook-Millstone Watershed Association, central New Jersey's first environmental group, protects clean water and the environment through a combination of conservation, advocacy, science and education. The nonprofit, membership supported organization, protects a 265-square-mile region spanning five counties and 26 towns. Become a member and learn