Invasive Plant Species Proliferation on Long Island

North Shore Land Alliance_2021 Fall Conservation news

As noted in a recent New York Times article, over the past 120 years, voracious insects and other pathogens have swept across North America with frightening regularity. They have devastated the American chestnut, the American elm and the Eastern hemlock as well as with ash and beech trees. These trees have anchored ecosystems, human economies and cultures.

Invasive plant species have long been a problem. This year’s accelerated growth, caused by factors associated with climate change, is a stark reminder of their threat to biodiversity and forest health. Invasive plants like porcelain-berry, mile-a-minute and multiflora rose are blanketing our landscape, overtaking native plants and trees and choking them to death.

Not all non-native species are invasive. The definition of a non-native or exotic species is one occurring outside its natural range as a result of actions by humans. According to the New York State Invasive Species Task Force (final report, fall 2005), an invasive species is a plant or animal that is (1) non-native to the ecosystem under consideration and (2) whose introduction causes or is likely to cause economic or environmental harm or harm to human health. The 12% or so of non-native species that are invasive wreak havoc on our land and water, devastating wildlife habitat and ecosystems. Over the last 50 years, invasive species have cost the world $1.4 Trillion in social and economic impacts (property values, agriculture, utility interruptions, fisheries, etc.) According to a 2013 National Invasive Species Awareness Week economic report:

The estimated damage from invasive species worldwide totals more than $1.4 trillion, or five percent of the global economy. The annual U.S. cost from invasives is estimated to be $120 Billion, with more than 100 Million acres affected (i.e., about the size of California).  A NASA report, heralding a novel effort to monitor the progress of alien species via satellite, placed the economic cost of invasive species in the United States between $100 Billion and $200 Billion.

Unfortunately, with many populations the spread has been so severe that eradication is no longer an option.

To grapple with management, in 2007 Nassau and Suffolk Counties – the first areas in New York State to do so – finalized Do Not Sell Lists, establishing legislation prohibiting the distribution of about 60 invasive plant species. The State followed a few years later with a comparable list.

A number of strategies help discourage the spread of invasives plant species on Long Island:

* Prevention of new invasions.
* Rapid detection and eradication of new invaders and outliers.
* Management of established infestations to prevent spread (contain, suppress, restore).
* Monitoring using established protocols.
* Public education.
* Research (species attributes, impacts, control, etc.)

What You Can Do to Help Stop the Spread of Invasive Plant Species on Long Island:

* Watch the NYS Department of Environment Conservation’s documentary Uninvited: The Spread of Invasive Species on YouTube  (See video below or copy and paste this link:

* Promote native alternatives to invasive plants.

* Do NOT purchase, plant or transplant any invasives (even if they’re legal).

* Expand your selection of native plant stock and grow species native to Long Island.20

* Monitor your property and eliminate invasives from your yard and garden when possible.

* If removal is not feasible, carefully remove fruits and berries to help minimize spread/reduce the seed source of invasive plants.

* Do NOT dump unwanted aquarium plants or animals or landscaping debris in natural areas and waterways.

* When visiting garden centers, find out if they’re in compliance with Do Not Sell legislation – notify County Consumer Affairs if they are not.

* Participate in Invasive Species Awareness Week.

* Visit the Long Island Invasive Species Management Area website for guidance in species identification and removal as well as how to document locations of invasives on mapping tool iMapInvasives (

* Volunteer with North Shore Land Alliance!