Invasive Species

Invasive species pose a serious risk to the health and balance of any ecosystem. With no natural predators to stunt growth, invasive species can form monocultures that out compete native species and are more susceptible to disease. To help stop the spread of invasive species, you can:

  • Remove invasive species from your own yard;
  • Tell your friends and neighbors about invasive species; and
  • Join the Cambridge Water Department's weed-out events at Fresh Pond!  Please email us or check out our volunteer page for more information.

Common invasive species found at the Fresh Pond Reservation and surrounding lands are listed below and are available in a pdf manual: Fresh Pond Reservation Invasive Species Manual.

 japanese barberry

Japanese Barberry, Berberis thunbergii

  • Multi-branched shrub with elliptical red berries
  • Remove plants in the spring by hand
 black locust

Black Locust, Robinia pseudoacacia

  • Large deciduous trees with thorns and compound leaves
 black swallow wort

Black Swallow-wort, Vincetoxicum nigrium

  • Perennial twining vine with opposite, dark green leaves
  • Dig up plant, leaving as few roots as possible.
  • Begin as plant appears, returning in August to remove before seed pods burst
 Asiatic Bittersweet

Asiatic Bittersweet, Celastrus orbiculatus

  • Woody vine with alternate leaves
  • Remove as much of plant as possible by pulling up roots and pulling down vines
  • All plant parts, including mature fruit, should be bagged and disposed of in a trash
 bittersweet nightshade

Bittersweet nightshade, Solanum dulcamara

  • Perennial vine grows to 3 m in length.
  • Hollow stems start out green and can turn a dark red to black color.
  • Leaves are alternate, ovate, and dark green in color with a purplish tinge.
 common buckthorn

Common Buckthorn, Rhamnus cathartica

  • Small understory tree with dark green leaves and curving veins
  • Sharp point at end of twigs
  • Grey bark
  • Pull saplings when found
 glossy buckthorn

Glossy Buckthorn, Rhamnus frangula

  • Gray bark with white spots
  • Dark green leave with curved veins
  • Understory tree
  • Pull saplings when found
 common burdock

Common Burdock, Arctium minus

  • Perennial. First year has alternate, large, heart-shaped leaves,
  • Second year sends out tall stalk with purple flowers.

Celandine, Chelidonium arvense

  • Biennial
  • When the branches or leaves are broken a yellowish-orange sap can be seen.

Cocklebur, Xanthium strumarium*

  • Native to the US but invasive in disturbed areas
  • Broad, grape like leaf with toothed edges
  • Dig up before flowers appear
 cow vetch

Cow vetch, Vicia cracca

  • Pea family plant with small compound leaves
  • Remove when found
 Asiatic dayflower

Asiatic Dayflower, Commelina communis

  • Annual pubesentstems grow distally to 1 m.
  • Lanceolateleaves 3-9 cm long
  • Bracts growing opposite leaf sites
 garlic mustard

Garlic Mustard, Alliaria petiolata

  • Biennial
  • Heart shaped leaves: 1st year single leaf, 2nd year multi-leaf structure with flowers
  • Distinct garlic smell
  • Remove by pulling from base of plant
 hedge bindweed

Hedge Bindweed, Convolvulus arvensis

  • Perennial vine of morning glory family
  • Arrowhead-shaped leaf
  • Pull up where possible on an annual basis
 yellow iris

Yellow Iris, Iris pseudacorus

  • Aquatic yellow iris flowers April to June
  • Broad, sword-shaped, erect, leaves
  • Dig up completely to remove, or cut down to base annually
  • Handle with gloves as plant can cause rash
 japanese honeysuckle

Japanese Honeysuckle, Lonicera japonica

  • Trailing woody vine
  • Use herbicides once per year in mid to late fall
 spotted knapweed

Spotted Knapweed, Centaurea maculosa

  • Perennial 2 to 4 feet tall, alternate, pale green leaves 1 to 3 inches long
  • Leaf margins of lower leaves divided and smooth but surface of the leaf is rough.
  • Hand pull twice per growing season
 japanese knotweed

Japanese Knotweed, Polygonum cuspidatum

  • Dense growing perennial grows to 3 to 10 ft high
  • Woody stem is hollow.
  • Large, alternate, dark green leaves
  • Small white flowers
  • To remove, cut three times per year
 european lily of the valley

European Lily of the Valley, Convallaria majalis

  • Perennial herb from a slender rhizome.
  • 2 to 3 basal leaves.
  • Flowers in cluster on one side.
  • Flowers are small, aromatic, white, bell-shaped.
 purple loosestrife

Purple Loosestrife, Lythrumsalicaria

  • Perennial wetland plant
  • Sends up reedy stalks that can grow to 8 ft
  • Currently being controlled by Galerucella beetle
 norway maple

Norway Maple, Acer platanoides

  • Maple with white sap
  • Pull or cut saplings in the spring

Mugwort, Artemisia vulgaris

  • Erect, perennial, 1 1/2' -7' tall
  • Stems mostly smooth
  • Leaves alternate, green above, with dense silvery fuzz below, oval in outline, divided into unequal, usually toothed segments.
  • Must be pulled or dug up completely
 multiflora rose

Multiflora Rose, Rosa multiflora

  • Dense shrub with small leaves
  • Cut or mow as close to ground as possible once per year

Phragmites, Phragmitesaustralis

  • Tall (up to 14 ft) golden grass
  • Perennial
  • Annual cutting, end of July

Pokeweed, Phytolacca americana

  • Native to the US but is invasive in disturbed areas
  • Large leaved tall plant with pink stems and pink inflorescences
  • Can be removed by hand pulling or digging
  • This plant is poisonous
 common privet

Common Privet, Ligustrum vulgare

  • Large shrub with ovate leaves
  • Cut back plants before berries are produced in September annually
 common ragweed

Common Ragweed,

Ambrosia artemisiifolia*

  • *Native to the US but is invasive in disturbed areas
  • Leaves are divided more than once, feathery or fern-like, lower leaves opposite, upper leaves alternate
  • Pull or cut in July
 bull thistle

Bull Thistle, Cirsium vulgare

  • Annual or biannual with tall spiny winged stems
  • Rosette in first year 2nd year can reach over 6 ft tall
  • Mow or cut annually to prevent seeding
 canada thistle

Canada Thistle, Cirsium arvense

  • Erect perennial thistle, .5 to 1 m tall
  • Pull twice per year in the spring
 tree of heaven

Tree of Heaven, Ailanthis altissima

  • Cut annually in spring and fall
  • Compound leaves, 2 to 3 ft in length
 white kerria jetbead

 White Kerria Jetbead, Rhodotyposscandens

  • Small plants; dig up all of plant, including roots. Larger infestations -cut shrubs to the ground in fall or winter
  • Leaves are opposite, simple and doubly serrate with a rough leaf surface.