The Long Island Invasive Species Management Area

Current Projects

Connetquot River State Park Invasive Species Prevention Zone

Alternatives to Ornamental Invasive Plants Demonstration Garden, Long Island Horticultural Research and Extension Center, Riverhead

Ludwigia peploides removal on the Peconic River

Brooklyn's Prospect Park Phragmites Control

Friends of the Long Pond Greenbelt - Vineyard Field Grassland Restoration Project

Fire Island National Seashore (FIIS) - Invasive Plant Inventory and Control Program

To download the Invasive Species Management Decision Tool CLICK HERE.

For information on obtaining a permit for mile-a-minute weevil release in New York CLICK HERE.

Connetquot River State Park Invasive Species Prevention Zone

Connetquot is New York State's first ISPZ. The State Parks regional environmental office has been implementing an Invasive Species Prevention Zone (ISPZ) plan at Connetquot River State Park Preserve in Oakdale. Wineberry, Japanese barberry, multiflora rose and Japanese stiltgrass were some of the species removed from the preserve.

With help from The Nature Conservancy, the preserve's 3,500 acres of pine barrens habitat were surveyed and mapped for invasive plants and the invasives found there are being actively monitored and removed. The goal is to remove all invasives from the park and monitor to guard against new and recurring invasions of common invasives and to detect and remove any new invasive species.



Alternatives to Ornamental Invasive Plants Demonstration Garden, Long Island Horticultural Research and Extension Center, Riverhead

The characteristics that tend to make a plant invasive also tend to make a good ornamental plant. In response to recent legislation banning the propagation and sale of many invasive plants, a list of replacements for invasive plants that are also ornamentals has recently been developed specifically for the Long Island region.

Creating a local demonstration garden consisting of these alternative plants is an important component of public outreach needed to maintain the vitality of Long Island's greenscapes and native biodiversity. The demonstration garden will be used to increase local nursery growers', landscapers', and homeowners' awareness of plants that can function as alternatives to ornamental invasives. The garden will also be used to demonstrate the ability of less common alternative plants to grow, thrive, and enhance Long Island landscapes.

The Alternatives to Ornamental Invasive Plants Demonstration Garden is located at the Long Island Horticultural Research & Extension Center, in Riverhead at 3059 Sound Ave. Donations of plants will be accepted beginning Spring 2009. If you are interested in donating plants, please contact Alexis Alvey, Cornell Cooperative Extension of Suffolk County's Nursery & Landscape Specialist, for more information:
Phone: 631-727-7850 ext. 213 



Ludwigia peploides removal on the Peconic River

Ludwigia peploides, more commonly known as water primrose, is a South American species that was first detected in the Peconic River in 2003. The Peconic Estuary Program and its partners have embarked on a multi-year monitoring and volunteer driven containment effort in an attempt to control the species in the Peconic River and prevent its spread to other Long Island waters. Since the initiation of the effort in the Spring of 2006, over 350 volunteers have spent many hours hand-pulling Ludwigia. Frequent monitoring suggests past and current efforts have been successful in controlling the invasive plant and project partners are hopeful that only small scale maintenance pulling will be required in the future.

For more information on invasives in the Peconic River and how you can help, go to




Brooklyn's Prospect Park Phragmites Control

For the past decade, land managers in Brooklyn's Prospect Park have been taking bites out of the lakeside Phragmites australis population. Their efforts have been multi-faceted: both through large-scale capital projects and in smaller scale in-house efforts of their Natural Resources Crew.

As part of a capital restoration project of the shoreline, Phragmites was removed using a coffer dam to draw down the water level and bulldozers to dig up rhizomes for complete removal of Phragmites from the site. The shoreline was re-graded to reduce Phragmites habitat, and planted with native aquatic plants.

In other areas, the staff has been covering stands of Phragmites with sheets of black plastic to kill it through solarization in situ.

The cover is left on the Phragmites for one to two years (with occasional patching to maintain effectiveness). This technique has been quite successful, with entire stands being wiped out. These areas will be planted with native aquatic plant species to replace the invasive reed.




Friends of Long Pond Greenbelt - Vineyard Field Grassland Restoration Project

Since 2006 FLPG has been implementing a native grasslands restoration project at Vineyard Field in Bridgehampton, a 39-acre property in the Long Pond Greenbelt preserved by the Town of Southampton in 1997 and surrounded by 30 acres of woodland preserved for drinking water protection by Suffolk County.

Through a Wildlife Habitat Incentives Program (WHIP) starter grant and with the guidance of Suffolk County Soil and Water Conservation District technicians, a three-stage, fifteen-year restoration plan was devised. Stage One targeted the removal of extensive autumn olive and Japanese knotweed populations. Arborists using brush hogs and chippers removed close to 30 acres of the autumn olive. Japanese knotweed stands were dug and covered with tarps, using both volunteer and paid labor. The area pictured, along with other smaller knotweed patches, were uncovered after three years and now host healthy specimens of local genome native grasses and wildflowers successfully introduced using seedlings grown by the Long Island Native Plants Initiative.

During Stage Two, efforts focused on controlling the resprouts of autumn olive, knotweed and the newly emergent mile-a-minute vine presence through brush hogging, mowing, and hand control activities. Stage Three consists of monitoring and annual maintenance mowing to control new infestations.

For further details on this restoration effort, visit


Fire Island National Seashore (FIIS) - Invasive Plant Inventory and Control Program


Fire Island National Seashore (FIIS) received funding in 2007 to support three years of invasive plant species management on site.  The initial work completed during the first three years was instrumental in showing the importance of an invasive species program.  After the grant money ran out FIIS staff biologists were able to justify using park base funding to support and maintain the program.

FIIS Natural Resource Management (NRM) staff have completed a full baseline inventory in all the federal tracts of FIIS and the William Floyd Estate.  Control efforts have been initiated in the park with some success.  Effectiveness of treatment varies depending on a few different factors, such as; location of the infestation, the size of the actual infestation, and the species.

After five years of invasive species management on Fire Island National Seashore it has become apparent that the park needs to re-evaluate the current program.  FIIS biologists are now prioritizing areas and particular infestations to manage.  A specific area of highest priority for the Seashore is the relatively unspoiled Otis Pike High Dune Wilderness Area (OPWA), which has been designated as the newest Invasive Species Prevention Zone (ISPZ).

NRM staff will continue to monitor for new invasive plant infestations throughout the park, control infestations that are considered high priority, and assesses past treatments to document the effectiveness.

Success Stories on FIIS so far…

  1. Japanese knotweed (Polygonum cuspidatum) located in the WFE: first controlled in 2007 using 10% Roundup®, but this proved ineffective.  In response, a retreatment with 12% Accord XT® was implemented in 2008.  The second treatment seemed to be extremely successful.  This site is monitored annually and any new emerging plants are immediately controlled.
  2. Tree of Heaven (Ailanthus altissima) located in the WFE: In May 2008 a basal bark treatment was applied using hand-held sprayers.  This site is monitored annually and a few seedlings are usually found which are pulled immediately.
  3. Japanese Barberry (Berberis thunbergii) located in the WFE:  NRM staff along with volunteers come out annually to treat infestations throughout the WFE by pulling.  Treatments seem to be effective and this method will be continued in the future.
  4. Japanese Black Pine (Pinus thunbergii) is being removed throughout the Otis Pike High Dune Wilderness Area.