Asian Longhorned Beetle


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Click on the titles below to learn more about CRISP's priority terrestrial plants!

Also check out the new horticulture watchlist from our friends at the Long Island Invasive Species Management Area (LIISMA)

It's a list of invasive species that have been planted here but have not yet escaped and become invasive. We can work to watch out for these invasives to prevent their establishment in our region! For more information as well as additional species lists including approaching plants and early detection plants go to Lisma's Website by clicking here.


berries_and_leaves.jpg warning_sign.gif Mile-a-Minute Vine 

(Persicaria perfoliata)

This plant hasn't been detected in the CRISP region yet, but it has been found near the region's borders and could appear in the Catskills at any time. Keep an eye out for its perfectly equalateral triangular leaves, downward pointing barbs, ocrea (round leaves that surround the stem to make little cups), and clusters of blue berries.  In the right conditions, this plant can grow up to 6 inches in a day! If it isn't controlled, mile-a-minute will create an inpenetrable mat that can shade out native plants and keep out people. To control Mile-a-Minute, pull plants up before they have time to develop berries during mid-summer (usually July). Dispose and compost all vines. 

Check out our video on Mile-A-Minute!



warning_sign.gif Giant Hogweed

(Heracleum mantegazzianum)

This terrestrial plant can reach heights of 15 feet. It is considered a noxious weed and coming into contact with it can cause some serious health effects. Giant hogweed's sap causes phytophotodermatitis (hypersensitivity to ultraviolet light) which can result in scars, blisters, and even blindness. Even though you may think this flowering plant looks pretty, it is a public health hazard. If you come into contact with this plant, seek medical attention! Report any giant hogweed sightings so a team can be sent to remove the dangerous plants for you! Crews can perform both chemical management and effective manual control to kill giant hogweed.

View CRISP's Giant Hogweed Management Plan

Check out our video on Giant Hogweed!



Asiatic Bittersweet

(Celastrus orbiculatus)

This woody vine was initially brought from east Asia and planted as an ornamental. It grows vigorously and smothers native vegetation, blocking them from sunlight.  This invader looks very similar to our native American bittersweet (Celastrus scandens), which we want around! Be sure to learn the differences between American and Asiatic bittersweet before you perform any control as the two are very similar. Consistently cutting vines and pulling up root shoots several times a year for several consecutive years will eventually weaken plants. Alternatively, careful application of glyphosate on cut stems can be done in the fall.

 Watch our video on Asiatic Bittersweet!



Norway Maple

(Acer platanoides)

Though it is widely sold as an ornamental and looks similar to our native maples, this tree is decreasing plant diversity in the region's forests.  Norway maple's shallow root system competes with surrounding vegetation and the dense shade generated by full-grown Norway maples prevents sunlight from reaching native understory species. Pull up seedlings and saplings!

Watch our video on Norway Maple!




Pale Swallow-wort

(Cynanchum rossicum)

This perennial twining vine is a member of the milkweed family. Pale swallow-wort grows rapidly, choking out native vegetation as it becomes established. Though its star-shaped flowers are attractive, this is not a species we want in the Catskills-- swallow-wort can alter grassland succession and make certain ecosystems uninhabitable by desired native species. To manage this species, consistently mow or cut its stems- don't pull it up! Disturbing the roots can actually help make more plants.

Check out our video on Pale Swallow-wort!