Weed Information: Amsinckia lycopsoides (fiddleneck, tarweed)
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Amsinckia lycopsoides (fiddleneck, tarweed)

Family: Boraginaceae

Description

Very similar to Amsinckia intermedia but with large hairy fornices which practically obstruct the throat of the flower tube. The plant generally very coarse with broad based hairs; these bases becoming white at maturity. Another closely related species, Amsinckia tessellata, can be distinguished by the fact that the sepals are unequal in width and reduced in number, commonly to 4 but sometimes to only 2 or 3.

Characteristics

Flower Color
  • Red (or pink)
  • Orange
  • Yellow-orange
  • Yellow
  • Multi-colored
Inflorescence Type (How the flowers are arranged on the plant)
  • Scorpioid
Number of Petals
  • 5 petals
Petal Separation
  • United > 75% of length
Petal Tip
  • Rounded
Flower Symmetry
  • Flowers regular
  • Flowers slightly irregular
Flower Length (Head length in the Asteraceae)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
Flower Width (Head width in the Asteraceae)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
Number of Sepals
  • 2 sepals
  • 3 sepals
  • 4 sepals
  • 5 sepals
Sepal Separation
  • Completely free to base
  • United at base < 25% length
Sepal Tip
  • Pointed
Flower Sex
  • Bisexual (perfect)
Number of Styles
  • 1 style
Number of Stamens
  • 5 stamens
Stamens Attached to the Petals
  • Stamens attached to the petals
Stamens Connate (united)
  • Filaments or anthers NOT united

Carpel Separation
  • Carpels united (or one)
Number of Carpels
  • 2 carpels
  • 4 carpels
Ovary Position
  • Superior (hypogynous)
Fruit Type
  • Nutlets, 4
Fruit Length at Maturity
  • 2 mm (.08 inch)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
Fruit Width at Maturity
  • 2 mm (.08 inch)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • Alternate
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Arcuate
  • Parallel
Petiole (leaf stem) Blade Ratio
  • Petiole absent (leaf sessile)
Leaf Length (blade PLUS petiole)
  • 1 - 2 cm (.40 - .80 inch)
  • 2 - 4 cm (.80 - 1.60 inches)
  • 4 - 10 cm (1.60 - 4.0 inches)
  • 1 - 2 dm (4.0 - 8.0 inches)
Leaf Width
  • 5 - 10 mm (.20 - .40 inch)
  • 1 - 2 cm (.40 - .80 inch)
Leaf Shape (simple leaves only)
  • Lanceolate
  • Linear or filiform
  • Oblong
Leaf or Leaflet Margin
  • Entire
Leaf or Leaflet Blade Base
  • Acuminate (attenuate)
  • Clasping
  • Rounded
Leaf or Leaflet Tip
  • Acute
Leaf or Leaflet Blade Surface
  • Antrorsely pubescent
  • Hirsute
  • Hispid or setose
  • Retrorsely pubescent
  • Spiny or prickly
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
  • Annual
Growth Habit (while flowering)
  • Erect, columnar (narrow)
  • Erect, spherical (bushy)
Plant Height at Maturity
  • 1 - 2 dm (4.0 - 8.0 inches)
  • 2 - 4 dm (8.0 - 16.0 inches)
  • 4 - 6 dm (1.3 - 2.0 feet)
Wind Dissemination
  • Not wind disseminated
Moisture Regime
  • Mesic
  • Arid
Chlorophyll
  • Present

Stem Cross Section
  • Round
Flowering Stem Leaves
  • Stem leaves greatly reduced
  • Stem uniformly leafy
Main Stem Branches
  • Main stem branched

Root or Vegetative Propagule
  • Tap Root

US State
  • Connecticut
  • Illinois
  • Massachusetts
  • Missouri
  • Mississippi
  • New Hampshire
  • New York
  • Ohio
  • Pennsylvania
  • Texas
  • Wisconsin
  • Alaska
  • California
  • Colorado
  • Idaho
  • Montana
  • North Dakota
  • Oklahoma
  • Oregon
  • Utah
  • Washington
  • Wyoming
  • Nebraska
Canadian Province or Territory
  • British Columbia

  • Gilkey`s Weeds of the Pacific Northwest, 1980 (ISBN 0-88246-039-0) See page: 231
  • Northwest Weeds, 1990 (ISBN 0-87842-249-8) See page: 99
  • Weeds, 1955 (1980) Walter Conrad Muenscher, ISBN# 0-8014-1266-8 See page: 357
  • Weeds of California and other Western States, 2007 (ISBN 13: 978-1-879906-69-3) See Page: 427
  • Weeds of Eastern Washington and Adjacent Areas, 1972 (LOC 72-83635) See page: 220
  • Weeds of the West, 1992 (ISBN 0941570-13-4) See page: 199
  • Weeds of the West, 2000 (ISBN 0941570-13-4) See page: 199
  • Listed as a `Weed` by the Biota of North America Program, 2008 X
  • Listed in the WSSA Composite List of Weeds X
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