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- Salix arctophila
Salix arctophila — northern willow
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Facts
Salix arctophila is known from a single remote, glacial basin on Katahdin in central Maine. Only staminate (i.e., pollen-bearing plants) are known from the site.
Habitat
Alpine or subalpine zones, talus and rocky slopes
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
- terrestrial
- New England state
- Maine
- Growth form
- the plant is a shrub (i.e., a woody plant with several stems growing from the base)
- Leaf type
- the leaf blade is simple (i.e., 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
- 20–40 mm
- Leaf blade width
- 15–30 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 thin and smooth
- Twig winter color
- 
                                
                                    - brown
- green
- red
- yellow
 
- 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
 - 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 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
- 1 or 2
 - 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 shrub (i.e., 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 cordate (heart-shaped, with rounded lobes)
 - Leaf blade edges
- the edge of the leaf blade has teeth
 - Leaf blade edges (Acer)
- NA
 - Leaf blade hairs
- the hairs on the leaf blade are different from the choices given
 - Leaf blade length
- 20–40 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 obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
 
 - 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 width
- 15–30 mm
 - 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 teeth
- 
                                
                                    - the leaf blade margin has teeth, which themselves have smaller teeth on them
- the leaf blade margin is crenate (with rounded teeth) or crenulate (with tiny, rounded teeth)
 
 - Leaf teeth hairs (Carya)
- NA
 - Leaf type
- the leaf blade is simple (i.e., 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 (i.e., lobed or unlobed but not separated into leaflets
 
- 
                        Place- Habitat
- terrestrial
 - New England state
- Maine
 - Specific habitat
- 
                                
                                    - alpine or subalpine zones
- talus or rocky slopes
 
 
- 
                        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)
- the branches are flexible, and do not 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
 - Pith shape
- the outline of the pith in a twig is roughly round
 - Twig papillae (Vaccinium species only)
- NA
 - Twig winter color
- 
                                
                                    - brown
- green
- red
- yellow
 
 - 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
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- absent
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
3. Salix arctophila Cockerell ex Heller NC
northern willow. Salix arctica Liebm.; S. arctophila Cockerell ex Heller var. lejocarpa (Anderss.) Schneid.; S. groenlandica Lundstr.; S. groenlandica Lundstr. var. lejocarpa (Anderss.) Lange • ME. Alpine ravines and slides. Two staminate individuals are known to occur in a remote basin on Katahdin, Piscataquis County, ME.
Native to North America?
Yes
Sometimes confused with
- Salix argyrocarpa:
- plants 20-70 cm tall, mature leaf blades prominently revolute, mostly 3.3-5.9 times as long as wide, and staminate aments 10-22 mm long (vs. S. arctophila, with plants 3-15 cm tall, mature leaf blades weakly revolute, mostly 1.2-3 times as long as wide, and staminate aments 19-54 mm long).
Synonyms
- Salix arctica Liebm.
- Salix arctophila Cockerell ex Heller var. lejocarpa (Anderss.) Schneid.
- Salix groenlandica Lundstr.
- Salix groenlandica Lundstr. var. lejocarpa (Anderss.) Lange
![Leaves: Salix arctophila. ~ By Arthur Haines. ~ Copyright © 2025 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-239x239/Salicaceae/salix-arctophila-le-ahaines-a.jpg) 
                        ![Plant form: Salix arctophila. ~ By Arthur Haines. ~ Copyright © 2025 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-239x239/Salicaceae/salix-arctophila-ha-ahaines-b.jpg) 
                         
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