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- Rhamnaceae
- Rhamnus
- Rhamnus alnifolia
Rhamnus alnifolia — alder-leaved buckthorn
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Facts
Alder-leaved buckthorn is a native shrub that tends to grow in calcareous wetlands (fens) in western and northern New England. It differs from all other members of the genus Rhamnus in our area by having flowers with five sepals, no petals, and five stamens (the other species have four of each). The flowers attract butterflies and the bright red fruits attract birds.
Habitat
Fens (calcium-rich wetlands), swamps
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Growth form
- the plant is a shrub (a woody plant with several stems growing from the base)
- Leaf type
- the leaf blade is simple (lobed or unlobed but not separated into leaflets)
- Leaves per node
- there is one leaf per node along the stem
- Leaf blade edges
- the edge of the leaf blade has teeth
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- armature on plant
- the plant does not have spines, prickles, or thorns
- Leaf blade length
- 40–100 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
- the fruit is fleshy
- Bark texture
- the bark of an adult plant is thin and smooth
- Twig winter color
-
- brown
- red
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
-
Buds or leaf scars
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
- Bud scar shape (Fraxinus)
- NA
- Collateral buds
- there are no collateral buds on the sides of the branches
- Superposed buds
- there are no superposed buds on the branch
-
Flowers
- Carpels fused
- the carpels are fused to one another
- Enlarged sterile flowers
- there are no enlarged sterile flowers on the plant
- Flower petal color
- NA
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Hairs on ovary (Amelanchier)
- NA
- Hypanthium present
- the flower has a hypanthium
- Inflorescence type
-
- the flowers grow out of the axil (point where a branch or leaf is attached to the main stem)
- the inflorescence is an umbel (with an axis so short it appears the flowers all originate from the same point)
- Number of pistils
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal fusion
- the perianth parts are separate
- Sepal cilia (Ilex)
- NA
- Stamen number
- 5
- Stamen position relative to petals
- the stamens are lined up with the petals (antepetalous)
-
Fruits or seeds
- Berry color
- black
- Fruit type (general)
- the fruit is fleshy
- Fruit type (specific)
-
- the fruit is a berry (fleshy, with the wall enclosing one or more sections, with two or more seeds)
- the fruit is a drupe (fleshy, with a firm inner ovary wall that encloses a single seed)
- Nut with spines (Fagaceae)
- NA
- Wings on fruit
- there are no wings on the fruit
-
Glands or sap
- Sap color
- the sap is clear and watery
- Stalked glands on fruit (Rosa)
- NA
-
Growth form
- Growth form
- the plant is a shrub (a woody plant with several stems growing from the base)
-
Leaves
- Hairs on upper side of leaf blade
- the upper side of the leaf is not hairy, or has very few hairs
- Leaf blade base shape
- the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
- Leaf blade edges
- the edge of the leaf blade has teeth
- Leaf blade edges (Acer)
- NA
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- the hairs on the leaf blade are different from the choices given
- Leaf blade length
- 40–100 mm
- Leaf blade scales
- there are no scales on the leaf blades
- Leaf blade shape
-
- the leaf blade is elliptic (widest near the middle and tapering at both ends)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade texture
- the leaf blade is herbaceous (has a leafy texture)
- Leaf blade translucent dots
- there are no translucent dots on the leaf blade
- Leaf blade vein pattern
- the main veins of the leaf blade are pinnate (the secondary veins branch off at intervals from the main central vein) and arcuate (slightly arched in the direction of the tip)
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf lobe tips (Quercus)
- NA
- Leaf midrib glands
- the midrib of the leaf blade lacks glands on the upper surface
- Leaf stalk
- the leaves have leaf stalks
- Leaf stalk nectaries
- there are no nectaries on the leaf stalk
- Leaf teeth
-
- the leaf blade margin is crenate (with rounded teeth) or crenulate (with tiny, rounded teeth)
- the leaf blade margin is serrate (with forward-pointing) or dentate (with outward-pointing) with medium-sized to coarse teeth
- Leaf teeth hairs (Carya)
- NA
- Leaf type
- the leaf blade is simple (lobed or unlobed but not separated into leaflets)
- Leaves per node
- there is one leaf per node along the stem
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets
- Stipules
- the plant has stipules
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- fens (calcium-rich wetlands)
- swamps
-
Scent
- Plant odor
- the plant does not have much of an odor, or it has an unpleasant or repellant odor
-
Stem, shoot, branch
- Aerial roots
- the plant has no aerial roots
- Bark texture
- the bark of an adult plant is thin and smooth
- Branch brittleness (willows only)
- NA
- Branch cross-section
- the branch is circular in cross-section, or it has five or more sides, so that there are no sharp angles
- First-year cane (Rubus)
- NA
- Twig papillae (Vaccinium species only)
- NA
- Twig winter color
-
- brown
- red
- Wings on branch
- the branch does not have wings on it
- armature on plant
- the plant does not have spines, prickles, or thorns
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- uncommon (S-rank: S3)
- Massachusetts
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
1. Rhamnus alnifolia ĽHér. N
alder-leaved buckthorn. CT, MA, ME, NH, VT. Swamps, fens, often associated with Thuja.
Native to North America?
Yes