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- Solanum
- Solanum rostratum
Solanum rostratum — horned nightshade
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Facts
Horned nightshade is native to the southwestern United States, but introduced in New England. "Horned" must refer to the extremely sharp and painful spines that densely cover this plant, even on the leaves and the fruits, which resemble burs from a horror movie. The plant is called buffalo-bur in the Southwest.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
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
- Flower petal color
- yellow
- Leaf type
-
- the leaves are compound (made up of two or more discrete leaflets
- the leaves are simple (i.e., lobed or unlobed but not separated into 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 five petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Stamen number
- 5
- Fruit type (general)
- the fruit is fleshy
- Fruit length
- 9–12 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 color
-
- the anthers show no hint of a pink, reddish or purplish tint
- there is a noticeable pink, reddish or purplish tint to the anthers
- Anther length
- 6–14 mm
- Anther opening
- the anthers have small holes or openings at the tips
- Anther spurs
- the anthers do not have spurs on them
- Calyx growth after flowering
- the calyx grows to cover or partially cover the fruit
- 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 palate
- no
- Corona lobe length
- 0 mm
- Epicalyx
- the flower does not have an epicalyx
- Epicalyx number of parts
- 0
- Filament surface
- the filament has rough hairs or scales on it
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower diameter
- 20–30 mm
- Flower number
- 3–15
- Flower petal color
- yellow
- Flower reproductive parts
- the flower has both pollen- and seed-producing parts
- 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
- the style is knob-like at the tip, and unbranched
- Fused stamen clusters
- NA
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Hairs on inflorescence
- the axis of the inflorescence has hairs entirely without glands
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Hypanthium length
- 0 mm
- Inflorescence length
- Up to 150 mm
- 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
- Marks on petals
- there are no noticeable marks on the petals
- Nectar spur
- the flower has no nectar spurs
- Number of branches in umbel
- 0
- Number of carpels
- 2
- Number of pistils
- 1
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Number of styles
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Perianth shape
- the perianth is rotate (platter-shaped, the corolla flattened, circular, with nearly horizontally spreading lobes)
- 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 folding in bud
-
- the petals are arranged some other way in bud
- the petals in bud meet exactly at the margins without overlapping (valvate)
- Petal hairs (Viola)
- NA
- Petal number
- 5
- Petal tips (Cuscuta)
- NA
- Raceme attachment (Veronica)
- 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 appearance
- the sepals are green or brown, and leaf-like in texture
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal color
- green to brown
- Sepal length
- 3–6 mm
- Sepal number
- 5
- Stamen attachment
- the stamens are attached at or near the bases of the petals or tepals
- Stamen lengths differ
- the stamens are didynamous (two long stamens and two short ones)
- Stamen morphology
- the stamens within a cycle differ in length or width
- Stamen number
- 5
- Stamen position relative to petals
- the stamens are lined up with the sepals
- Stamen relative length
- anything
- Stamens fused
- the stamens are not attached to one another
- Staminodes
- there are no staminodes on the flower
- Style petal-like
- the styles are not petal-like
- 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
- Capsule color (Viola)
- NA
- Capsule ribs
- NA
- Capsule splitting
- NA
- Carpel beak length
- 0 mm
- Fruit (pyxis) dehiscence
- NA
- Fruit beak length
- 0 mm
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 9–12 mm
- Fruit length relative to sepals
- the fruit is shorter than its associated sepals
- Fruit locules
- two
- Fruit shape
- the fruit is spherical
- 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)
- Fruit width
- 9–12 mm
- Legumes (Fabaceae)
- NA
- Mericarp length
- 0 mm
- Mericarp segment shape (Desmodium)
- NA
- Other markings on berry
- the ripe berries are mostly one color without spots or streaks
- Ovary stipe
- the ovary or fruit does not have a stipe
- Placenta arrangement
- the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Septum in fruit (Brassicaceae)
- NA
- 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
- Growth form
- the plant is an herb (it has self-supporting stems)
- 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
- there are spines on the plant
-
Leaves
- Bracteole edges
- NA
- Bracteole length
- 0 mm
- Bracteole number (Apiaceae)
- 0
- Bracteole shape
- NA
- Bracteoles
- there are no bracteoles on the plant
- Bracts in plantain (Plantago)
- NA
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment length to width ratio (compound lvs only)
- 0
- Final leaf segment width (compound lvs only)
- 0 mm
- Floral bract texture
- NA
- Floral bracts
- the flower does not have bracts
- Flower bract length
- 0 mm
- Hairs on leaf stalk
- the petiole has hairs on it
- Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
- Hairs on upper side of leaf
- the upper side of the leaf is fuzzy or hairy
- Hooked hairs on underside of leaf
- no
- Inflated hairs on leaf
- the leaf blade does not have inflated hairs on it
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade base
- the leaf has a distinct leaf stalk (petiole)
- Leaf blade bloom
- the underside of the leaf has no noticeable bloom
- Leaf blade edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- the leaf blade has branched hairs
- Leaf blade length
- 50–150 mm
- Leaf blade primary vein pattern
- the secondary veins branch off at intervals from the primary vein
- Leaf blade shape
-
- the leaf blade is oblong (rectangular but with rounded ends)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade vein pattern
- the major veins of the leaf blade branch, but do not rejoin
- Leaf blade veins
- the leaf blade has one main vein running from the base towards the tip (it may or may not have secondary veins)
- Leaf blade width
- 30–70 mm
- Leaf duration
- the leaves drop off in winter (or they whither but persist on the plant)
- Leaf form
- the leaves are green, with an expanded blade and a leaf-like texture
- Leaf hair orientation
- the hairs are standing up straight or curved in different directions
- Leaf shiny
- the upper side of the leaf is dull or slightly shiny
- Leaf spines
- there are spines along the leaf edges
- 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 length
- 20–60 mm
- Leaf teeth and lobes
-
- 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
- Leaf type
-
- the leaves are compound (made up of two or more discrete leaflets
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaf types
-
- NA
- There is a gradual change in appearance of the leaves from the base (or near the base) of the plant to those from further up on the stem, with leaves progressively changing as one moves higher on the stem (often becoming shorter, or less toothed/lobed, and/or with shorter petioles).
- Leaf variation
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaflet number
- 0
- Leaflet petiolules
- NA
- Leaves per node
- there is one leaf per node along the stem
- Pinnately compound leaf type
- NA
- Specific leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Stipels
- NA
- Stipule edges
- NA
- Stipule features
- NA
- Stipule fused to leaf stalk
- NA
- Stipule length
- 0 mm
- Stipule shape
- NA
- Stipules
- there are no stipules on the plant
- Teeth per side of leaf blade
- 0
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Branched tendrils
- NA
- Direction of stem hairs
- the hairs point mostly upwards to outwards
- Hair between stem nodes
- the stem has hairs between the nodes
- 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
- 30–100 cm
- Stem bloom
- there is no powdery or waxy film on the stem
- Stem hair distribution
- the hairs on the stem are distributed more of less uniformly
- Stem nodes swollen
- the stem is not swollen at the nodes
- Stem orientation
- the stems are upright or angled outwards
- Stem roughness between nodes
- the stem does not feel rough
- Stem succulence
- the stems are not succulent
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
- Wings on stem
- the stem does not have wings on it
Wetland status
Not classified
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
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
10. Solanum rostratum Dunal E
horned nightshade. Androcera rostrata (Dunal) Rydb.; Solanum cornutum, auct. non Lam. • CT, MA, ME, NH, RI, VT. Fields, gardens, dumps, waste areas.
Native to North America?
No
Sometimes confused with
- Solanum carolinense:
- petals light purple to white and leaf blades prominently toothed to somewhat lobed with shallow sinuses (vs. S. rostratum, with petals yellow and leaf blades evidently 1- to 2-times pinnately lobed).
Synonyms
- Androcera rostrata (Dunal) Rydb.
- Solanum cornutum, auct. non Lam.