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- Zanthoxylum americanum
Zanthoxylum americanum — common prickly-ash
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Facts
Called common prickly-ash for its compound ash-like leaves and its abundant prickles, this species is actually a member of the mostly-tropical citrus family (Rutaceae), and its lemony-scented foliage and flowers bear this out. The inconspicuous, greenish flowers are very fragrant and attract bees (which make a tasty honey from its nectar) and many other insects. The caterpillars of the giant swallowtail butterfly (Papilio cresphontes) eat the foliage.
Habitat
Anthropogenic (man-made or disturbed habitats), forest edges, forests, meadows and fields, ridges or ledges, shrublands or thickets, talus and rocky slopes, woodlands
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
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- 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 compound (i.e., made up of two or more discrete leaflets
- Leaves per node
- there is one leaf per node along the stem
- Leaf blade edges
-
- the edge of the leaf blade has no teeth or lobes
- 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 has spines, prickles, or thorns
- Leaf blade length
- 152–203 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
- gray
- purple
- 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
- Leaf scar arrangement
- there is one leaf scar per node on the stem or twig
- Superposed buds
- there are superposed buds above the main (terminal) bud
- Winter bud stalks
- the winter buds have no stalks
-
Flowers
- Anther color
- the anthers show no hint of a pink, reddish or purplish tint
- Carpels fused
- the carpels are fused to one another
- Enlarged sterile flowers
- there are no enlarged sterile flowers on the plant
- Flower appearance
- the flowers appear before the leaves
- Flower petal color
- yellow or green
- 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 does not have a hypanthium
- Inflorescence hairs
- there are no hairs on the inflorescence
- Inflorescence position
- the inflorescences grow on older branches
- Inflorescence type
-
- the flowers grow out of the axil (point where a branch or leaf is attached to the main stem)
- the inflorescence is a fascicle (compact cluster of flowers)
- Number of pistils
-
- 3
- 4
- 5
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes only one cycle of petals or sepals
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal fusion
- the perianth parts are separate
- Sepal appearance
- NA
- Sepal cilia (Ilex)
- NA
- Sepal tip glands
- there are no glands at the tips of the sepal lobes
- Sepals fused only to sepals
- NA
- Stamen number
-
- 10
- 8
- 9
- 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 fleshy
- Fruit type (specific)
- the fruit is a follicle (has one ovary that splits along one side to release the 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 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
- the base of the leaf blade is rounded
- Leaf blade base symmetry
-
- the leaf blade base is asymmetrical
- 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 no teeth or lobes
- 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
- 152–203 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 oblong (rectangular but with rounded ends)
- Leaf blade texture
- the leaf blade is herbaceous (has a leafy texture)
- Leaf blade translucent dots
- the leaf blade has translucent dots on it
- 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 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
- there are no nectaries on the leaf stalk
- Leaf stalk shape
- the leaf stalk is not flattened
- Leaf teeth
- 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 compound (i.e., made up of two or more discrete leaflets
- Leaves per node
- there is one leaf per node along the stem
- Specific leaf type
- the leaf is compound, with a single terminal leaflet and more than two additional leaflets
- Stipules
- there are no stipules on the plant, or they fall off as the leaf expands
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- edges of forests
- forests
- man-made or disturbed habitats
- meadows or fields
- ridges or ledges
- shrublands or thickets
- talus or rocky slopes
- woodlands
-
Scent
- Plant odor
- the plant has a pleasantly aromatic 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
- Lenticels on twigs
- there are no lenticels on the twigs, or they are very hard to see
- 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 hairs, but the hairs do not have glands
- Twig papillae (Vaccinium species only)
- NA
- Twig scales
- there are no scales on the twig surface
- Twig winter color
-
- brown
- gray
- purple
- Wings on branch
- the branch does not have wings on it
- armature on plant
- the plant has spines, prickles, or thorns
Wetland status
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
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
- fairly widespread (S-rank: S4)
- New Hampshire
- historical (S-rank: SH), endangered (code: E)
From Flora Novae Angliae dichotomous key
1. Zanthoxylum americanum P. Mill. N│E
common prickly-ash. CT, MA, ME, NH, RI, VT. Fields, roadsides, forests, forest fragments and borders, woodlands, sometimes associated with rocky and/or ledgy soils. This species is introduced in ME and native to the other states.
Native to North America?
Yes
Sometimes confused with
- Phellodendron amurense:
- leaves opposite, branches unarmed, and fruit a drupe (vs. Z. americanum, with leaves alternate, branches armed with prickles, and fruit a fleshy follicle).