How Did Water Chestnuts Get To America

Water Chestnut

Rosette of water chestnut leaves floating on water

On this page:

New York locations
Identification
How it spreads
Environmental impact
Direction
Best management practices for removal projects

H2o chestnut is an aquatic invasive establish that is native to Eurasia and Africa. It was introduced in the Usa in the mid-1800' as an ornamental plant. Around 1884, water anecdote was constitute growing in Collins Lake about Scotia, NY. Water anecdote colonizes shallow areas of freshwater lakes and ponds and ho-hum-moving streams and rivers and negatively impacts aquatic ecosystems and water recreation.

Water chestnut fact sheet (PDF)

New York Locations

Water anecdote has been found in more than twoscore counties in New York State. For a map of where water chestnut has been documents, please visit iMapInvasives' interactive mapper (leaves DEC website).

Identification

H2o chestnut is an annual found with a submerged stem 12-15 feet long that has fine roots that anchor information technology to the soil. Its floating leaves are triangular in shape with saw-toothed edges and hollow air-filled stems. Leaves form a rosette around a central bespeak. Its tiny flowers by and large bloom in June and are four-petaled and white. Each rosette tin can produce upwardly to 20 hard nut with 4-inch spines that have barbs along them. Seeds within fruits can remain feasible for up to 12 years.

How It Spreads

Spiny water chestnut nutlets in hand

Water chestnut spreads past rosette and fruits detaching from the stem and floating to another area. They besides spread by clinging to floating objects including recreational watercraft, the pads of boat trailers, and fishing equipment.

Environmental Touch on

Water chestnuts course dense mats of rooted vegetation that can exist very difficult to get through in a boat, kayak, canoe, or when swimming. Water chestnut fruits are often found forth the shoreline and bottom of waterways - they have very abrupt spines with barbs that can cause painful wounds when stepped on. The dumbo mats of vegetation shade out native aquatic plants that provide food and shelter to native fish, waterfowl, and insects. Decomposition of these dense mats reduces dissolved oxygen levels and may kill fish. Holding values forth shorelines of infested waters may too decrease.

How You Tin Help

Prevention is the most effective method for dealing with invasive species. If they are never introduced, they never go established.

Clean, drain, and dry out your watercraft, trailer, and equipment before and subsequently each apply. Regulation vi NYCRR Part 576 requires everyone who uses watercraft on public waters to, when possible, use the post-obit methods to fully decontaminate your equipment:
- Make clean the outside of the watercraft and trailer with high pressure (2500 psi) hot water (140°F) for 10 seconds.
- Flush the inside of the motor and all compartments (bilge, alive well, allurement buckets, anchor, etc.) with hot water (140°F) for two minutes.
- Soak fishing gear and equipment in hot h2o (140°F) for 2 minutes.
Dump bait bucket h2o where it came from or on land.
View more information on how to clean your boat.

Early detection of infestations helps to reduce removal costs and ecological impacts.

If you think you've found h2o anecdote please take several photos and submit a report to iMapInvasives (leaves DEC website).
Become a Chestnut Chaser! We know that h2o chestnut is underreported in New York State. Each summer we encourage folks to survey their favorite pond holes, lakes, ponds, and nearby waterbodies for water chestnut and submit reports to iMapInvasives.
Share the h2o chestnut fact canvass (PDF) with others.

Management

Dense mat of water chestnut plants

Water chestnut tin be controlled using manual, mechanical, and chemical methods. As with all other infestations, early detection is key for containing and controlling spread. Dec is currently funding inquiry on biocontrol - a study of the effectiveness of predator insects from water anecdote'southward native range - in controlling the spread of water chestnut.

The smaller the size of the infestation, the more easily it tin can exist eradicated, and its economic and ecological impacts reduced. Because water chestnut is an annual establish, constructive control tin exist achieved if seed formation is prevented.

A site may exist a candidate for eradication (eliminating the plant from the expanse entirely) if:

pocket-size in size (trace-sparse density),
detected and treated early on (no significant seed banking concern has been established),
located within an isolated body of water, or is an isolated population within a larger bounding main (unlikely to exist re-infested),
clean, drain, dry out participation prevents new introductions,
there is condom access for manual (hand-removal) efforts.

A site may be a candidate for suppression and containment (reducing the size of the patch or preventing it from spreading) if:

medium in size (sparse-medium density),
a long-term delivery to management/monitoring as seeds in the seed bank may be viable for up to 12 years,
make clean, drain, dry participating prevents new introductions,
strategic removal of portions of the infestation would protect high quality native plant beds or other of import features.

A site may be a candidate for maintaining access (preventing the patch from obstructing use) if:

large in size (medium-dumbo density),
population (and seed bank) has been established for many years,
repeated introductions are probable from other nearby infestations due to tides/streamflow/motorboat transport, etc.,
next to boat ramps, docks, pond beaches, or sampling sites where need for access makes continued maintenance necessary.

Best Management Practices for Removal Projects

Hand-pulling/Manual Removal

Manus-pull rosettes when they first appear (mid-June to early on July), earlier seeds are developed.
Remove equally much of each plant equally possible, including the stems, any developing seeds, and roots.
Avoid pulling native aquatic establish species, if possible.
Identify access areas, disposal site, and location for storing harvested plants during the drying procedure.
Start at the edge of the infestation and work towards the center.
If possible, revisit the site repeatedly to pull plants that continue to sprout throughout the growing flavour.
Repeat institute removal early each growing season until the seed bank has been depleted.
Monitor site for a minimum of 12 years to ensure seed bank has been depleted and no new introductions have occurred from other sources.

Mechanical Removal/Machine Harvesting

Conduct an aquatic establish survey to decide whether harvesting would also eliminate native and/or protected species.
Place access areas, disposal site, and location for storing harvested plants during the drying process.
Harvesting machines can be used when rosettes offset appear (mid-June to early July) before seeds are developed.
Remove as much of each plant equally possible, including the stems, any developing seeds, and roots.
Repeat institute removal early each growing flavour until the seed depository financial institution has been depleted.
Monitor site for a minimum of 12 years to ensure seed depository financial institution has been depleted and no new introductions have occurred from other sources.
Avoid mechanical harvesting if water anecdote is accompanies by other invasive species that reproduce via fragmentation such every bit Eurasian watermifoil (leaves DEC website).

Chemic/Herbicide Command

Aquatic herbicides approved for utilise in New York tin can be effective including florpyrauxifen-benzyl, imazamox, ii, 4-D, and glyphosate.
Herbicides must be applied by a licensed applicator according to label requirements and whatever necessary permit requirements.
Behave an aquatic plant survey to decide whether products would likewise touch native and/or protected species.
Identify boundaries for the treatment area and determine any risks to non-target species.
Repeat herbicide treatment or combine with manual and/or mechanical control methods until seed bank has been depleted.
Monitor site for a minimum of 12 years to ensure seed banking company has been depleted and no new introductions have occurred from other sources.

Disposal

For minor infestations, plants can be places in black trash numberless and left in the sun earlier placing in trash; or
dispose of plants in compost, far abroad from water sources, or allow to dry in piles far from water and and so incinerate.
Larger infestations will require careful coordination with local municipalities to transport plants/seeds away from water sources and compost them on land without gamble of spreading the plants.