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- Descurainia pinnata
Descurainia pinnata — western tansy-mustard
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Facts
Western tansy-mustard has a broad distribution across North America, but in New England it is rare and restricted to calcareous cliffs in New Hampshire and Vermont. Occurrences in Massachusetts and Maine are considered introduced. In areas of North America where the plant is common, it has long been used by Native Americans for food, especially the seeds.
Habitat
Anthropogenic (man-made or disturbed habitats), cliffs, balds, or ledges, ridges or ledges, 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
- Massachusetts
- New Hampshire
- Vermont
- Flower petal color
-
- blue to purple
- pink to red
- yellow
- Leaf type
- the leaves are compound (made up of two or more discrete leaflets
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Number of sepals, petals or tepals
- there are four petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- both the petals and sepals are separate and not fused
- Stamen number
- 6
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit length
- 4–17 mm
-
Clonal plantlets
- Bulbils
- the plant does not appear to have bulbils
- Bulblets replace flowers
- there are no bulblets where the flowers are located
-
Flowers
- Anther opening
- the anthers have narrow slits or furrows that run lengthwise along the anthers
- Anther spurs
- the anthers do not have spurs on them
- Calyx symmetry
- there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
- Carpels fused
- the carpels are fused to one another
- Cleistogamous flowers
- there are no cleistogamous flowers on the plan
- Corolla morphology
- NA
- Corolla palate
- no
- Corona lobe length
- 0 mm
- Epicalyx
- the flower does not have an epicalyx
- Epicalyx number of parts
- 0
- Filament surface
- the filament is smooth, with no hairs or scales
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower petal color
-
- blue to purple
- pink to red
- yellow
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Flowers sunken into stem
- no
- Form of style
-
- NA
- the style is knob-like at the tip, and unbranched
- Fused stamen clusters
- NA
- Fusion of sepals and petals
- both the petals and sepals are separate and not fused
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Inflorescence one-sided
- the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
- Inner tepals (Rumex)
- NA
- Nectar spur
- the flower has no nectar spurs
- Number of pistils
- 1
- Number of sepals, petals or tepals
- there are four petals, sepals, or tepals in the flower
- Number of styles
- 0–1
- 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 and sepal colors
-
- blue to purple
- pink to red
- yellow
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal folds or pleats
- the petals of the flower do not have folds or plaits
- Petal hairs (Viola)
- NA
- Petal number
- 4
- Petal tips (Cuscuta)
- NA
- Reproductive system
- all the flowers have both carpels and stamens (synoecious)
- Scales inside corolla
- no
- Sepal and petal color
- the sepals are different from the petals
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal number
- 4
- Stamen attachment
- the stamens are not attached to the petals or tepals
- Stamen number
- 6
- Stamen position relative to petals
- NA
- Staminodes
- there are no staminodes on the flower
- Umbel flower reproductive parts
- NA
- Upper lip of bilabiate corolla
- NA
-
Fruits or seeds
- Achene relative orientation
- NA
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Capsule ribs
- NA
- Capsule splitting
-
- NA
- the capsule splits by two main valves, teeth or pores
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 4–17 mm
- Fruit locules
- two
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
- the fruit is a silique (greater than three times as long as wide, and dehisces by two valves, leaving the persistent replum to which the seeds are attached, found only in the Brassicaceae)
- Legumes (Fabaceae)
- NA
- Mericarp length
- 0 mm
- Mericarp segment shape (Desmodium)
- NA
- Other markings on berry
- NA
- Ovary stipe
- the ovary or fruit does not have a stipe
- Placenta arrangement
- the plant has parietal placentation, where ovules develop on the wall or slight outgrowths of the wall forming broken partitions within a compound ovary
- Rows of seeds in fruit (Brassicaceae)
- there are two or more rows of seeds in each locule of the fruit
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Septum in fruit (Brassicaceae)
- The fruit is either not compressed or is compressed parallel to the septum; therefore, the fruit and its septum are about the same width
- Wings on fruit
- the fruit does not have wings on it
- prickles on fruits
- the fruits do not have thorn-like defensive structures
-
Glands or sap
- Glands on leaf blade
- the leaf blades do not have glandular dots or scales
- Sap
- the sap is clear and watery
- Sap color
- the sap is clear
-
Growth form
- Horizontal rooting stem
- the plant does not have stolons
- Lifespan
- the plant lives only a single year or less
- Parasitism
- the plant is not parasitic
- Plant color
- the leaves or young stems of the plant are green
- Plants darken when dry
- no
- Spines on plant
- the plant has no spines
-
Leaves
- Bracteole number (Apiaceae)
- 0
- Bracts in plantain (Plantago)
- NA
- Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade base
-
- the leaf has a distinct leaf stalk (petiole)
- the leaf has no stalk
- 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 lobes, or it has both teeth and lobes
- Leaf blade length
- 10–150 mm
- Leaf blade shape
-
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is rhombic (roughly diamond-shaped)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf form
- the leaves are green, with an expanded blade and a leaf-like texture
- Leaf spines
- there are no spines on the leaf edges
- Leaf type
- the leaves are compound (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 has a row of two or more lobes on each side of the central axis
- the leaf has a row of two or more lobes on each side of the central axis, and each lobe itself has rows of lobes on each side of the lobe's central axis
- Stipels
- there are no stipels at the bases of the petiolules
- Stipule features
- NA
- Stipules
- there are no stipules on the plant
-
Place
- Habitat
- terrestrial
- New England state
-
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- cliffs, balds, or ledges
- man-made or disturbed habitats
- ridges or ledges
- talus or rocky slopes
-
Stem, shoot, branch
- Branched tendrils
- NA
- Flowering stem cross-section
- the flowering stem is circular, or with lots of small angles so that it is roughly circular
- Hairs between stem nodes
- at least some of the hairs on the stem are branched
- Hooked hairs on stem between nodes
- no
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Plant height
- 80–92 cm
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- 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.
ssp. brachycarpa
- Massachusetts
- not applicable (S-rank: SNA)
- New Hampshire
- unrankable (S-rank: SU), Ind (code: Ind)
var. brachycarpa
- Vermont
- extremely rare (S-rank: S1)
Subspecies and varieties
Our subspecies is Descurainia pinnata (Walt.) Britt. ssp. brachycarpa.
From Flora Novae Angliae dichotomous key
2. Descurainia pinnata (Walt.) Britt. ssp. brachycarpa (Richards.) Detling N│EC
western tansy-mustard. Descurainia brachycarpa (Richards.) O.E. Schulz; D. pinnata (Walt.) Britt. var. brachycarpa (Richards.) Fern.; Sisymbrium brachycarpum Richards.; Sophia brachycarpa (Richards.) Rydb. • MA, ME, NH, VT. Cliffs, limestone headlands, wool waste. This species is native to NH and VT and is introduced elsewhere.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Descurainia incana:
- with siliques narrow-linear in outline, mostly 0.7-1.2 mm wide, and leaf blades usually eglandular (vs. D. pinnata, with siliques clavate or subclavate in outline, 1-2 mm wide, rounded to obtuse at the apex, and leaf blades usually stipitate glandular).
- Descurainia sophia:
- siliques narrow-linear in outline, mostly 0.5-0.8 mm wide, and leaf blades usually eglandular (vs. D. pinnata, with siliques clavate or subclavate in outline, 1-2 mm wide, rounded to obtuse at the apex, and leaf blades usually stipitate glandular).
Synonyms
- Descurainia brachycarpa (Richards.) O.E. Schulz
- Descurainia pinnata (Walt.) Britt. var. brachycarpa (Richards.) Fern.
- Sisymbrium brachycarpum Richards.
- Sophia brachycarpa (Richards.) Rydb.