Weed Information: Triglochin maritima (arrowgrass, seaside)
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Triglochin maritima (arrowgrass, seaside)

Family: Juncaginaceae

Description

A slender, almost grass-like, plant of wet saline to alkaline sites. The flowers in a narrow terminal spike, flower parts in threes. A native plant included in weed references due to its toxicity rather than weediness.

Characteristics

Flower Color
  • Yellow
  • Yellow-green
  • Green
Inflorescence Type (How the flowers are arranged on the plant)
  • Terminal raceme
  • Terminal spike
Number of Petals
  • 0 (no petals)
  • 3 petals
  • 6 petals
Petal Separation
  • Completely free to base
Petal Tip
  • Pointed
  • Rounded
Flower Symmetry
  • Flowers regular
Flower Length (Head length in the Asteraceae)
  • 2 mm (.08 inch)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
Flower Width (Head width in the Asteraceae)
  • 2 mm (.08 inch)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
Number of Sepals
  • sepals lacking
  • 3 sepals
  • 6 sepals
Sepal Separation
  • Completely free to base
Sepal Tip
  • Pointed
  • Rounded
Flower Sex
  • Bisexual (perfect)
Number of Styles
  • 1 style
Number of Stamens
  • 6 stamens
Stamens Attached to the Petals
  • Stamens NOT attached to the petals
Stamens Connate (united)
  • Filaments or anthers NOT united

Carpel Separation
  • Carpels united (or one)
  • Carpels separated
Number of Carpels
  • 6 - 9 carpels
Ovary Position
  • Superior (hypogynous)
Fruit Type
  • Follicle
Fruit Length at Maturity
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
Fruit Width at Maturity
  • 1 mm (.04 inch) or less
  • 2 mm (.08 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • All basal
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Parallel
Petiole (leaf stem) Blade Ratio
  • Petiole absent (leaf sessile)
Leaf Length (blade PLUS petiole)
  • 4 - 10 cm (1.60 - 4.0 inches)
  • 1 - 2 dm (4.0 - 8.0 inches)
  • 2 - 4 dm (8.0 - 16.0 inches)
  • 4 - 6 dm (1.3 - 2.0 feet)
Leaf Width
  • 1 - 5 mm (.04 - .20 inch)
Leaf Shape (simple leaves only)
  • Linear or filiform
Succulence
  • Succulent
  • Not succulent
Leaf or Leaflet Margin
  • Entire
Leaf or Leaflet Blade Base
  • Clasping
Leaf or Leaflet Tip
  • Acute
  • Rounded (obtuse)
Leaf or Leaflet Blade Surface
  • Glabrous (NO hairs)

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)
Plant Height at Maturity
  • 2 - 4 dm (8.0 - 16.0 inches)
  • 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
  • Aquatic
  • Semi-aquatic
  • Seasonally saturated
Chlorophyll
  • Present

Stem Cross Section
  • Round
Flowering Stem Leaves
  • Stem leafless
Main Stem Branches
  • Main stem unbranched

Root or Vegetative Propagule
  • Rhizomatous

US State
  • Connecticut
  • Delaware
  • Illinois
  • Kansas
  • Massachusetts
  • Maine
  • Michigan
  • New Hampshire
  • New Jersey
  • New York
  • Ohio
  • Pennsylvania
  • Wisconsin
  • Indiana
  • Maryland
  • Rhode Island
  • Vermont
  • Alaska
  • Arizona
  • California
  • Colorado
  • Iowa
  • Idaho
  • Minnesota
  • Montana
  • North Dakota
  • New Mexico
  • Nevada
  • Oklahoma
  • Oregon
  • South Dakota
  • Utah
  • Washington
  • Wyoming
  • Nebraska
Canadian Province or Territory
  • British Columbia
  • New Brunswick
  • Nova Scotia
  • Ontario
  • Prince Edward Island
  • Quebec
  • Alberta
  • Manitoba
  • Newfoundland
  • Saskatchewan
  • Yukon
  • Nunavut
  • Northwest Territory
Other
  • St. Pierre and Miquelon
  • Labrador

  • Weeds and Poisonous Plants of Wyoming and Utah 1987 (ISBN 0-941570-06-1) See page: 262
  • Weeds of Alberta, 1983 Alberta Environmental Centre Agdex 640-4, See page: 7
  • Weeds of California, 1970, State of California Publications and Documents. See page: 39, 40
  • Weeds of Colorado, 1990 Cooperative Extension, Colorado State Univ. Bulletin 521A, See page: 18
  • Weeds of Nebraska and the Great Plains, 1994 (ISBN 0939870-00-4) See page: 320
  • Weeds of the Northern U.S, and Canada, 1999 Royer and Dickinson, (ISBN# 1-55105-221-0) See page: 12 - 13
  • Weeds of the West, 1992 (ISBN 0941570-13-4) See page: 360
  • Weeds of the West, 2000 (ISBN 0941570-13-4) See page: 358
  • Weeds of Utah, 1971 UAES Special Report 21, See page: 5
  • 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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