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• All other flowering non-woody plants
• Other herbaceous, flowering plants with alternate leaves
• Lupinus polyphyllus

Lupinus polyphyllus Lindl.

blue lupine

Facts About

Blue lupine is native to the Western United States and, in spite of its attractive appearance, is quite invasive in New England. Numerous garden varieties exist, and can escape from cultivation. It has also been intentionally introduced in some places.

Habitat

Anthropogenic (man-made or disturbed habitats), meadows and fields

Characteristics

• 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 attachment

  • the anther is attached by its base to the filament
  • the anther is attached near its midpoint to the filament

  Calyx symmetry

  there is only one way to evenly divide the calyx (the calyx is bilaterally symmetrical)

  Carpels fused

  NA

  Flower description

  the flower has a superior ovary and a hypanthium

  Flower length

  9–15 mm

  Flower petal color

  • blue to purple
  • pink to red
  • white

  Flower reproductive parts

  the flower has both pollen- and seed-producing parts

  Flower symmetry

  there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)

  Fused stamen clusters

  there is one cluster of fused stamens

  Fusion of petals

  • the petals are fused into a corolla tube
  • the petals are separate

  Horns in hoods (Asclepias)

  NA

  Hypanthium

  the flower has a hypanthium

  Inflorescence length

  150–600 mm

  Inner tepals (Rumex)

  NA

  Length of flower stalk

  3–15 mm

  Length of peduncle

  30–80 mm

  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

  1

  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

  NA

  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 hairs (Viola)

  NA

  Petal length

  12–14 mm

  Petal number

  5

  Petal tips (Cuscuta)

  NA

  Raceme attachment (Veronica)

  NA

  Reproductive system

  all the flowers have both carpels and stamens (synoecious)

  Sepal and petal color

  • the petals and sepals are similar
  • the sepals are different from the petals

  Sepal appearance

  the sepals are green or brown, and leaf-like in texture

  Sepal appendages (Oenothera)

  NA

  Sepal length

  4–7 mm

  Sepal number

  5

  Sepals fused only to sepals

  the sepals are fused to each other (not other flower parts), at least near their bases

  Spur length

  0 mm

  Spur number

  NA

  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

  10

  Stamens fused

  the stamens are attached to one another at or near their bases

  Style petal-like

  the styles are not petal-like

  Umbel flower reproductive parts

  NA

• Fruits or seeds

  Achene relative orientation

  NA

  Achene shape

  NA

  Achene surface (Polygonum)

  NA

  Achene type

  NA

  Capsule color (Viola)

  NA

  Carpel beak length

  0 mm

  Fruit (pyxis) dehiscence

  NA

  Fruit cross-section

  the fruit is at least somewhat flattened

  Fruit features (Brassicaceae)

  NA

  Fruit length

  25–40 mm

  Fruit shape

  the fruit is obloid (longer than wide and with rounded ends)

  Fruit type (general)

  the fruit is dry and splits open when ripe

  Fruit type (specific)

  the fruit is a legume (a fruit that splits into two valves, but only has a single carpel; think of a pea pod)

  Fruit width

  7 mm

  Hair type on fruit

  the hairs on the fruits are simple (not branched), don’t have glands, and are not woolly

  Hairs on fruit

  the fruits have hairs on them

  Legumes (Fabaceae)

  the legume has valves that split elastically and coil after they split

  Mericarp length

  0 mm

  Mericarp segment shape (Desmodium)

  NA

  Ovary stipe

  the ovary or fruit does not have a stipe

  Ovary stipe length

  0 mm

  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)

  NA

  Schizocarpic fruit compression

  NA

  Schizocarpic fruit segments

  0

  Seed length

  4 mm

  Seed number

  5–9

  Seed surface

  the seed is smooth or without clear markings

  Septum in fruit (Brassicaceae)

  NA

• 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)

  Lifespan

  the plant lives more than two years

  Parasitism

  the plant is not parasitic

  Plant color

  the leaves or young stems of the plant are green

  Spines on plant

  the plant has no spines

  Underground organs

  the plant has a caudex (the root mass is firm and hardened at the top)

• Leaves

  Bracteole number (Apiaceae)

  0

  Bracteoles

  the plant has bracteoles between the primary bracts and the flowers

  Bracts in plantain (Plantago)

  NA

  Final leaflet length (compound lvs only)

  70–150 mm

  Final leaflet width (compound lvs only)

  15–30 mm

  Floral bracts

  the flower has one or more bracts associated with it

  Flower bract length

  7–11 mm

  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 not hairy, or it has very few hairs

  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 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 is entire (has no teeth or lobes)

  Leaf blade flatness

  the leaf is flat (planar) at the edges

  Leaf blade hairs

  the leaf blade has simple hairs with no glands, and not tangled or wooly

  Leaf blade primary vein pattern

  the major veins radiate out from one point at the base

  Leaf blade shape

  • the leaf blade is lanceolate (lance-shaped; widest below 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)

  Leaf blade surface colors

  the upper side of the leaf blade is relatively uniform in color

  Leaf blade texture

  the leaf blade is herbaceous (has a leafy texture)

  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 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 flat against the leaf surface, mostly pointing towards the leaf tip

  Leaf shiny

  the upper side of the leaf is dull or slightly shiny

  Leaf spines

  there are no spines on the leaf edges

  Leaf stalk

  the leaves have leaf stalks

  Leaf stalk length

  30–450 mm

  Leaf teeth and lobes

  the edge of the leaf blade is entire (has no teeth or lobes)

  Leaf type

  the leaves are compound (made up of two or more discrete leaflets

  Leaf types

  the basal and stem leaves are similar, or they gradually change between the lower and higher parts of the plant

  Leaf variation

  the basal leaves are larger or toothier than the upper leaves

  Leaflet number

  9–17

  Leaves per node

  there is one leaf per node along the stem

  Pinnately compound leaf type

  NA

  Specific leaf type

  the leaf has lobes that radiate from the base, somewhat like a hand

  Stipule features

  NA

  Stipule fused to leaf stalk

  the stipules are fused to the petioles for some or most of their length

  Stipule length

  5–30 mm

  Stipules

  the plant has stipules

  Teeth per side of leaf blade

  0

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • man-made or disturbed habitats
  • meadows or fields

• Stem, shoot, branch

  Branched tendrils

  NA

  Direction of stem hairs

  • the hairs are pressed flat against the plant, pointing towards the plant's tip
  • the hairs point mostly upwards to outwards

  Flowering stem cross-section

  the flowering stem is circular, or with lots of small angles so that it is roughly circular

  Hair between stem nodes

  the stem has hairs between the nodes

  Hairs between stem nodes

  the hairs on the stem are plain, without glands or branches, and not tangled

  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

  50–150 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 spacing

  the plant is growing in tufts, or compact clusters with closely spaced stems, or it is densely matted together in clumps, cushionlike

  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

Occurs only in non-wetlands. (Wetland indicator code: UPL)

New England Distribution and Conservation Status

Exact status definitions can vary from state to state. For details, please check with your state.

Information from Dichotomous Key of Flora Novae Angliae