Invasives
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Eurasian Watermilfoil (Myriophyllum spicatum)
Eurasian watermilfoil, also called spike watermilfoil, is an emergent, herbaceous aquatic plant. Stems grow to the water surface, usually extending 3 to 10, but as much as 33, feet in length and frequently forming dense mats. Stems of Eurasian milfoil are long, slender, branching, hairless, and become leafless toward the…
![](https://cisma-suasco.org/wp-content/uploads/2018/03/european-alder.png)
European Alder (Alnus glutinosa (L.) Gaertn.)
European alder, also known as common alder or black alder is a tree that grows 40-50 ft in height. Its branches are alternate. Its leaves are simple, oval, 2 to 4 inches long, 2 to 3 inches wide, with a rounded or slightly notched tip, have a doubly serrate margin,…
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European Rusty Willow and Gray Willow (Salix atrocinerea (L.) Gaertn.) and Gray Willow (S.cinerea (L.) Gaertn.)
European rusty willow is a tall shrub or small tree that grows up to 50 feet tall; it has smooth gray-green bark with a waxy texture and raised ridges in the wood. Gray willow is a multi-stemmed shrub that may grow up to 20 feet tall. The two willows are…
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Fig Buttercup (Ficaria verna Huds.)
Fig buttercup, also called lesser celandine, is a low perennial herb that grows from tuberous roots. Most plants are no more than 6 inches tall, although some reach 1 foot. The shiny leaves are dark green, often paler on their undersides. Leaves have long petioles and may be oblong, triangular,…
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Garlic Mustard (Alliaria petiolata)
Garlic mustard is a cool season biennial herb with stalked, triangular to heart-shaped, coarsely toothed leaves that give off an odor of garlic when crushed. First-year plants appear as a rosette of green leaves close to the ground. Rosettes remain green through the winter and develop into mature flowering plants…
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Giant Hogweed (Heracleum mantegazzianum)
*If found report here to Mass. Dept. of Agricultural Resources (MDAR). Giant hogweed is an herbaceous perennial species that grows over 15 feet in height. It is native to the Caucasus Mountains and southwest Asia. The stem, which is blotched with purple and covered with short hairs, is 2 to…
![](https://cisma-suasco.org/wp-content/uploads/2018/03/glossy-buckthorns-300x201.jpg)
Glossy Buckthorn (Frangula alnus)
Glossy buckthorn is a tall shrub or small tree reaching 20-25 feet in height and 10 inches in diameter. Most often it grows in a large shrub growth form, having a few to several stems from the base. The shrub has spreading, loosely-branched crowns. The leaves are thin, glossy, and…
![](https://cisma-suasco.org/wp-content/uploads/2018/02/Hydrilla-300x200.jpg)
Hydrilla (Hydrilla verticillata)
Hydrilla, also known as water thyme, is a submerged, aquatic, perennial herbaceous plant that can grow from depths of 20-25 feet. The stems have whorls of 3-8 tiny, strap-like leaves that are 0.2 to 0.8 inches long and 0.07-0.15 inches wide. The leaves have saw-toothed margins visible with a hand lens. Hydrilla…
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Japanese Barberry (Berberis thunbergii)
Japanese barberry is a dense, deciduous, spiny shrub that grows 2 to 8 ft. high. The branches are brown, deeply grooved, somewhat zigzag in form and bear a single very sharp spine at each node. The leaves are small (½ to 1 ½ inches long), oval to spatula-shaped, green, bluish-green,…
![](https://cisma-suasco.org/wp-content/uploads/2023/11/pinus-thunbergii-wb-pnw-200x300.jpg)
Japanese black pine (Pinus thunbergii)
Japanese black pine is a tree native to Japan and China. In the US, it was used ornamentally and can crowd out native species when it escapes garden environments. The trunks of Japanese black pine are often uniquely twisted, making them a popular choice for landscaping and arboretums. They can…