Weed Information: Lupinus polyphyllus (lupine, large-leaved)
Back to Plant List

Lupinus polyphyllus (lupine, large-leaved)

Family: Fabaceae

Description

This native wildflower is the largest member of the genus in the Pacific Northwest. The leaves have from 6 to 18 large leaflets and the plants are often as much as a meter tall. This species commonly occurs west of the Cascades but can also be found in moist sites in the mountains east of the Cascades. Some members of this genus are toxic.

Characteristics

Flower Color
  • Blue-purple
  • Purple
  • White
  • Multi-colored
Inflorescence Type (How the flowers are arranged on the plant)
  • Terminal raceme
Number of Petals
  • 5 petals
Petal Separation
  • Completely free to base
  • United > 75% of length
Petal Tip
  • Bilobed
  • Rounded
Flower Symmetry
  • Flowers strongly irregular
Flower Length (Head length in the Asteraceae)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.6 inch)
Flower Width (Head width in the Asteraceae)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
Number of Sepals
  • 5 sepals
Sepal Separation
  • United from 25% - 75% length
Sepal Tip
  • Pointed
Flower Sex
  • Bisexual (perfect)
Number of Styles
  • 1 style
Number of Stamens
  • 10 stamens
Stamens Attached to the Petals
  • Stamens NOT attached to the petals
Stamens Connate (united)
  • Filaments united, monodelphous

Carpel Separation
  • Carpels united (or one)
Number of Carpels
  • 1 carpel
Ovary Position
  • Superior (hypogynous)
Fruit Type
  • Capsule, 1-celled
  • Legume
Fruit Length at Maturity
  • 2.5 cm (1.0 inch)
  • 3.0 cm (1.2 inches)
  • 3.5 cm (1.4 inches)
  • 4.0 cm (1.6 inches)
  • 4.5 cm (1.8 inches)
  • 5.0 cm (2.0 inches)
Fruit Width at Maturity
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.60 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • Alternate
Leaf Type
  • Compound palmate > 5 leaflets
Stipules
  • Foliaceous 4-10 mm (.16 - .40 in) long
Tendrils
  • Tendrils absent
Venation
  • Palmate
  • Pinnate
Petiole (leaf stem) Blade Ratio
  • Petiole 25% - 75% total length
  • Petiole > 75% total length
Leaf Length (blade PLUS petiole)
  • 1 - 2 dm (4.0 - 8.0 inches)
  • 2 - 4 dm (8.0 - 16.0 inches)
Leaf Width
  • 4 - 10 cm (1.6 - 4.0 inches)
Leaf or Leaflet Margin
  • Entire
Leaf or Leaflet Blade Base
  • Acuminate (attenuate)
Leaf or Leaflet Tip
  • Acute
Leaf or Leaflet Blade Surface
  • Glabrous (NO hairs)
  • Pubescent
Succulence
  • Not succulent

Milky Juice
  • Juice NOT milky (watery)
Woodiness
  • Herbaceous
Spines or Thorns
  • Spines or Thorns ABSENT
Aromatic (vegetative structures)
  • Not aromatic
Life Cycle
  • Perennial
Growth Habit (while flowering)
  • Erect, columnar (narrow)
  • Erect, spherical (bushy)
Plant Height at Maturity
  • 4 - 6 dm (1.3 - 2.0 feet)
  • 6 - 8 dm (2.0 - 2.6 feet)
  • 8 - 10 dm (2.6 - 3.3 feet)
  • 1 - 1.5 meters (3.3 - 5.0 feet)
Wind Dissemination
  • Not wind disseminated
Moisture Regime
  • Seasonally saturated
  • Mesic
Chlorophyll
  • Present

Stem Cross Section
  • Hollow (flowering stem at maturity)
  • Round
Flowering Stem Leaves
  • Stem leaves greatly reduced
  • Stem uniformly leafy
Main Stem Branches
  • Main stem unbranched
  • Main stem branched

Root or Vegetative Propagule
  • Fibrous
  • Tap Root

US State
  • Connecticut
  • Illinois
  • Massachusetts
  • Maine
  • Michigan
  • New Hampshire
  • New York
  • Wisconsin
  • Maryland
  • Vermont
  • Alaska
  • California
  • Idaho
  • Minnesota
  • Montana
  • Nevada
  • Oregon
  • Washington
Canadian Province or Territory
  • British Columbia
  • New Brunswick
  • Nova Scotia
  • Ontario
  • Prince Edward Island
  • Quebec
  • Alberta
  • Newfoundland

  • Gilkey`s Weeds of the Pacific Northwest, 1980 (ISBN 0-88246-039-0) See page: 169
  • Selected Weeds of Oregon, 1985 and 1989 Supplement (s) Oregon State Dept. of Agriculture, See page: s24
  • Listed as a `Weed` by the Biota of North America Program, 2008 x
Back to Plant List