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- Salix nigra
Salix nigra — black willow
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Facts
One of the world's largest willows when mature, black willow is so-named for its dark ebony bark. It most commonly grows in floodplains and riversides. Black willow provides some of the only economically important wood in the willow genus (Salix). The light but sturdy wood was once used for making artificial limbs, and is still used for fashioning boxes and making pulp. Birds eat the catkins, and other animals eat the bark and twigs. It is well-adapted to streamsides and is planted to reduce erosion. Many willows (Salix species) have bitter-tasting bark that contains derivatives of salicylic acid, the main compound in aspirin.
Habitat
Floodplain (river or stream floodplains), shores of rivers or lakes, 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
- Rhode Island
- Vermont
- Growth form
- the plant is a tree
- 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
- 50–150 mm
- Leaf blade width
- 5–17 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Bark texture
- the bark of an adult plant is ridged or plated
- Twig winter color
-
- brown
- gray
- orange
- red
- Bud scale number
- there is one scale on the winter bud, and it covers the scale like a cap
-
Buds or leaf scars
- Bud scale number
- there is one scale on the winter bud, and it covers the scale like a cap
- Bud scar shape (Fraxinus)
- NA
- Collateral buds
- there are no collateral buds on the sides of the branches
- Leaf scar arrangement
- there is one leaf scar per node on the stem or twig
- Superposed buds
- there are no superposed buds on the branch
- Winter bud distribution
- the winter buds are distributed fairly evenly along the twig
- Winter bud scales
- the winter bud is perulate (partially or completely covered with one or more scales)
- Winter bud shape
- the winter buds are lanceoloid (lance-shaped, widest below the middle and tapering to the ends)
- Winter bud stalks
- the winter buds have no stalks
-
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 is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Hairs on ovary (Amelanchier)
- NA
- Hypanthium present
- the flower does not have a hypanthium
- Inflorescence position
- the inflorescences grow on the twigs
- Inflorescence type
- the inflorescence is an ament (catkin; slender, usually pendulous inflorescence with crowded unisexual flowers)
- Number of pistils
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower lacks sepals and petals
- Petal appearance
- NA
- Petal fusion
- NA
- Sepal appearance
- NA
- Sepal cilia (Ilex)
- NA
- Sepal tip glands
- NA
- Sepals fused only to sepals
- NA
- Stamen number
-
- 3
- 4
- 5
- 6
- 7
- Stamen position relative to petals
- NA
- Stamens fused
- the stamens are not fused to one another
-
Fruits or seeds
- Berry color
- NA
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
- the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
- 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 tree
-
Leaves
- Hairs on underside of leaf blade
-
- the underside of the leaf has hairs on it
- the underside of the leaf has no hairs
- Hairs on upper side of leaf blade
-
- the upper side of the leaf is fuzzy or hairy
- 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 base symmetry
- the leaf blade base is symmetrical
- Leaf blade bloom
- the underside of the leaf has no noticeable bloom
- 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
-
- at least some of the hairs on the leaf blade are reddish-brown, and they do not have glands
- the hairs on the leaf blade are different from the choices given
- Leaf blade length
- 50–150 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 lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is linear (very narrow with more or less parallel sides)
- Leaf blade texture
-
- the leaf blade is coriaceous (has a firm, leathery 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 non-arcuate (not arched towards the leaf tip)
- Leaf blade veins
- the leaf blade has one main vein running from the base toward the tip
- Leaf blade width
- 5–17 mm
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf form
- the plant is broad-leaved (with broadly flattened leaf blades)
- 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 attachment to leaf
- the petiole attaches at the basal margin of the leaf blade
- Leaf stalk nectaries
- the leaf stalk has nectaries on it
- Leaf stalk shape
- the leaf stalk is not flattened
- Leaf teeth
-
- the leaf blade margin has teeth, which themselves have smaller teeth on them
- the leaf blade margin is serrulate (with forward-pointing) or denticulate (with outward-pointing) with tiny 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
- Rhode Island
- Vermont
- Specific habitat
-
- river or stream floodplains
- shores of rivers or lakes
- 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 ridged or plated
- Branch brittleness (willows only)
- the branches are brittle, and break easily
- 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
- Lenticels on twigs
- there are clearly lenticels on the twigs
- Pith shape
- the outline of the pith in a twig is roughly round
- Pith type
- the pith inside the twig is solid, completely filled with spongy tissue
- Short shoots
- there are no peg- or knob-like shoots present
- Twig bloom
- there is no bloom on the twig
- Twig hairs
- the twigs have few or no hairs on them
- Twig papillae (Vaccinium species only)
- NA
- Twig scales
- there are no scales on the twig surface
- Twig winter color
-
- brown
- gray
- orange
- 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
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
18. Salix nigra Marsh. N
black willow. Salix denudata Raf.; S. falcata Pursh; S. nigra Marsh. var. brevifolia Anderss.; S. nigra Marsh. var. falcata (Pursh) Torr. • CT, MA, ME, NH, RI, VT; generally limited in ME to the southern half of the state. Shorelines, swamps, riparian forests, river banks.
Native to North America?
Yes
Sometimes confused with
- Salix alba:
- leaf blades with a whitish bloom on the lower surface, without or with minute stipules at the base of the leaf stalk (vs. S. nigra, with leaf blades green on the lower surface, with small, but evident, stipules at the base of the leaf stalk). Salix lucida: shrubs to 6 m tall, leaf blades 11-43 mm wide, and capsules 5-7 mm tall (vs. S. nigra, which are tall shrubs or trees 5-20 m tall, leaf blades mostly 7.5-17 mm wide, and capsules 3-5 mm tall).
Synonyms
- Salix denudata Raf.
- Salix falcata Pursh
- Salix nigra var. brevifolia Anderss.
- Salix nigra var. falcata (Pursh) Torr.