Weed Information: Cynoglossum officinale (houndstongue)
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Cynoglossum officinale (houndstongue)

Family: Boraginaceae

Description

Houndstongue has small, but beautiful, dark red to reddish-purple tubular flowers. The four nutlets are covered with hooked bristles which allow the seeds to be dispersed by passing animals. Recent evidence has shown this species to be toxic to livestock due to the presence of pyrrolizidine alkaloids. The entire plant has a sweetish musty odor which some people say smells like dirty socks and others claim smells like hot buttered popcorn!

Characteristics

Flower Color
  • Red (or pink)
  • Purple
  • Red-purple
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
Flower Length (Head length in the Asteraceae)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
Flower Width (Head width in the Asteraceae)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
Number of Sepals
  • 5 sepals
Sepal Separation
  • Completely free to base
  • United at base < 25% length
Sepal Tip
  • Pointed
  • Rounded
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
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
Fruit Width at Maturity
  • 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 bur-like

Leaf Arrangement
  • Alternate
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Arcuate
  • Pinnate
Petiole (leaf stem) Blade Ratio
  • Petiole absent (leaf sessile)
  • Petiole < 25% total length
  • Petiole 25% - 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
  • 2 - 4 cm (.80 - 1.6 inches)
  • 4 - 10 cm (1.6 - 4.0 inches)
Leaf Shape (simple leaves only)
  • Elliptic
  • Lanceolate
  • Oblanceolate
Leaf or Leaflet Margin
  • Entire
Leaf or Leaflet Blade Base
  • Acuminate (attenuate)
  • Clasping
Leaf or Leaflet Tip
  • Acute
  • Rounded (obtuse)
Leaf or Leaflet Blade Surface
  • Pubescent
Succulence
  • Not succulent

Milky Juice
  • Juice NOT milky (watery)
Woodiness
  • Herbaceous
Spines or Thorns
  • Spines or Thorns ABSENT
Aromatic (vegetative structures)
  • Not aromatic
  • Aromatic
Life Cycle
  • Biennial
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)
  • 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
  • Mesic
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
  • Alabama
  • Arkansas
  • Connecticut
  • Delaware
  • Georgia
  • Illinois
  • Kansas
  • Kentucky
  • Massachusetts
  • Maine
  • Michigan
  • Missouri
  • North Carolina
  • New Hampshire
  • New Jersey
  • New York
  • Ohio
  • Pennsylvania
  • South Carolina
  • Tennessee
  • Virginia
  • Wisconsin
  • West Virginia
  • Indiana
  • Maryland
  • Rhode Island
  • Vermont
  • Arizona
  • California
  • Colorado
  • Iowa
  • Idaho
  • Minnesota
  • Montana
  • North Dakota
  • New Mexico
  • Nevada
  • Oregon
  • South Dakota
  • Utah
  • Washington
  • Wyoming
  • Nebraska
Canadian Province or Territory
  • British Columbia
  • New Brunswick
  • Nova Scotia
  • Ontario
  • Quebec
  • Alberta
  • Manitoba
  • Saskatchewan
Other
  • District of Columbia

  • The Biology of Canadian Weeds: Canadian Journal of Plant Science Vol:68Pg.763
  • California Growers Weed Identification Handbook, 1968 - 1998 University of California Publication # 4030-1, See page: 261
  • Common Weeds of the Canadian Prairies, 1963 (Cat# A53-1136-1) See page: 34
  • Gilkey`s Weeds of the Pacific Northwest, 1980 (ISBN 0-88246-039-0) See page: 235
  • How to Know the Weeds, 1972, (ISBN# 0-697-04880-2) See page: 120
  • Northwest Weeds, 1990 (ISBN 0-87842-249-8) See page: 99
  • Ontario Weeds, 1992 Agdex 640, Publication #505 See page: 172
  • Some Important Michigan Weeds, 1951 Mich. Ag. Exp. Station Bulletin #304, See page: 165
  • South Dakota Weeds, 1967 South Dakota State University, See page: 135
  • South Dakota Weeds 2002 South Dakota Dept. of Ag. 523 E. Capitol, Foss Bldg. Pierre, South Dakota 57501 See page: 158
  • Weed Seeds of the Great Plains, 1993 University of Kansas# 92-125-B ISBN# 0-7006-0651-3 See index #: 162
  • Weeds, 1955 (1980) Walter Conrad Muenscher, ISBN# 0-8014-1266-8 See page: 357, 358
  • Weeds and Poisonous Plants of Wyoming and Utah 1987 (ISBN 0-941570-06-1) See page: 106
  • Weeds of California and other Western States, 2007 (ISBN 13: 978-1-879906-69-3) See Page: 433
  • Weeds of Canada, 1970 Canada Dept. of Ag., Pub. # 948, See page: 140
  • Weeds of Colorado, 1990 Cooperative Extension, Colorado State Univ. Bulletin 521A, See page: 120
  • Weeds of Eastern Washington and Adjacent Areas, 1972 (LOC 72-83635) See page: 224
  • Weeds of Nebraska and the Great Plains, 1994 (ISBN 0939870-00-4) See page: 184
  • Weeds of the Midwestern United States & Central Canada, University of Georgia 2010, ISBN#0-8203-3506-1 See page: 137
  • Weeds of the North Central States, 1981 Univ. of Illinois, Urbana - Champaign Bulletin # 772, See page: 145
  • Weeds of the Northern United States and Canada, 1964 Montgomery See page: 127
  • Weeds of the South, University of Georgia 2009, ISBN#0-8203-3046-9 See page: 119
  • Weeds of the West, 1992 (ISBN 0941570-13-4) See page: 202
  • Weeds of the West, 2000 (ISBN 0941570-13-4) See page: 202
  • Weeds of Utah, 1971 UAES Special Report 21, See page: 70
  • Listed as a `Weed` by the Biota of North America Program, 2008 X
  • Listed in the WSSA Composite List of Weeds X
  • Cyrtorhyncha cymbalaria ssp. alpina / Ranunculaceae / buttercup, shore
  • 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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