Weed Information: Erigeron strigosus (fleabane, rough)
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Erigeron strigosus (fleabane, rough)

Family: Asteraceae

Description

There are many native wildflowers in this genus, but this species is an annual to biennial weed. Its long, narrow, hairy stem leaves are similar to the closely related species, horseweed (Conyza canadensis), but rough fleabane tends to be more widely branched and have larger flowers. Erigeron annuus is extremely similar but is generally taller, more leafy, the basal leaves rounder and sharply toothed, and the stem hairs longer and more spreading.

Characteristics

Flower Color
  • Red (or pink)
  • Blue
  • White
Inflorescence Type (How the flowers are arranged on the plant)
  • Corymb
  • Head
  • Panicle
  • Solitary, terminal
Number of Petals
  • 5 petals
  • more than 10 petals
Petal Separation
  • Completely free to base
  • United > 75% of length
Petal Tip
  • Pointed
  • Rounded
Flower Symmetry
  • Flowers regular
Flower Length (Head length in the Asteraceae)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
Flower Width (Head width in the Asteraceae)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.60 inch)
  • 2.0 cm (.80 inch)
  • 2.5 cm (1.0 inch)
  • 3.0 cm (1.2 inches)
Number of Sepals
  • sepals lacking
  • more than 10 sepals
Sepal Separation
  • Completely free to base
Sepal Tip
  • Pointed
Flower Sex
  • Unisexual (monoecious or dioecious)
  • Bisexual (perfect)
Number of Styles
  • Styles lacking (male flowers only)
  • 1 style
Number of Stamens
  • stamens lacking (female flowers only)
  • 5 stamens
Stamens Attached to the Petals
  • Stamens attached to the petals
Stamens Connate (united)
  • Anthers united, syngynoecious

Carpel Separation
  • Carpels united (or one)
Number of Carpels
  • 0 (male flowers only or plants producing spores)
  • 1 carpel
Ovary Position
  • Inferior (epigynous)
Fruit Type
  • Achene
Fruit Length at Maturity
  • 2 mm (.08 inch)
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
Fruit Width at Maturity
  • 1 mm (.04 inch) or less
  • 2 mm (.08 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • Alternate
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Parallel
  • Pinnate
Petiole (leaf stem) Blade Ratio
  • Petiole < 25% total length
  • Petiole 25% - 75% total length
Leaf Length (blade PLUS petiole)
  • 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
  • 1 - 2 cm (.40 - .80 inch)
  • 2 - 4 cm (.80 - 1.6 inches)
  • 4 - 10 cm (1.6 - 4.0 inches)
Leaf Shape (simple leaves only)
  • Elliptic
  • Lanceolate
  • Linear or filiform
  • Oblanceolate
Leaf or Leaflet Margin
  • Entire
  • Serrate
Leaf or Leaflet Blade Base
  • Acute (cuneate)
  • Acuminate (attenuate)
Leaf or Leaflet Tip
  • Acuminate (attenuate)
  • Acute
Leaf or Leaflet Blade Surface
  • Hirsute
  • Pubescent
  • Strigose
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
  • Biennial
Growth Habit (while flowering)
  • Erect, columnar (narrow)
Plant Height at Maturity
  • 4 - 6 dm (1.3 - 2.0 feet)
  • 6 - 8 dm (2.0 - 2.6 feet)
Wind Dissemination
  • Fruit, seed, or spore wind borne
Moisture Regime
  • Seasonally saturated
  • 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
  • Fibrous
  • Tap Root

US State
  • Alabama
  • Arkansas
  • Connecticut
  • Delaware
  • Florida
  • Georgia
  • Illinois
  • Kansas
  • Kentucky
  • Louisiana
  • Massachusetts
  • Maine
  • Michigan
  • Missouri
  • Mississippi
  • North Carolina
  • New Hampshire
  • New Jersey
  • New York
  • Ohio
  • Pennsylvania
  • South Carolina
  • Tennessee
  • Texas
  • Virginia
  • Wisconsin
  • West Virginia
  • Indiana
  • Maryland
  • Rhode Island
  • Vermont
  • California
  • Colorado
  • Iowa
  • Idaho
  • Minnesota
  • Montana
  • North Dakota
  • Oklahoma
  • Oregon
  • South Dakota
  • Washington
  • Wyoming
  • Nebraska
Canadian Province or Territory
  • British Columbia
  • New Brunswick
  • Nova Scotia
  • Ontario
  • Prince Edward Island
  • Quebec
  • Alberta
  • Manitoba
  • Newfoundland
  • Saskatchewan
Other
  • District of Columbia
  • St. Pierre and Miquelon

  • Common Weeds of Canada, Mulligan 1987 (ISBN 0-910053-59-9) See page: 114
  • Field Guide To The Common Weeds Of Kansas, 1983 (ISBN 0-7006-0233-X) See page: 116
  • How to Know the Weeds, 1972, (ISBN# 0-697-04880-2) See page: 188
  • Manual of Ohio Weeds, 1931 Ohio Ag. Exp. Station Bull. # 475, See page: 99
  • Nebraska Weeds, 1979 Nebraska Dept. of Ag., Lincoln NE, See page: 207
  • Ontario Weeds, 1992 Agdex 640, Publication #505 See page: 230
  • Representative Missouri Weeds and Their Control, 1941 Univ. of Missouri Ag. Exp Station Bulletin #433, See page: 191
  • Some Important Michigan Weeds, 1951 Mich. Ag. Exp. Station Bulletin #304, See page: 221
  • South Dakota Weeds, 1967 South Dakota State University, See page: 180
  • South Dakota Weeds 2002 South Dakota Dept. of Ag. 523 E. Capitol, Foss Bldg. Pierre, South Dakota 57501 See page: 191
  • Weed Seeds of the Great Plains, 1993 University of Kansas# 92-125-B ISBN# 0-7006-0651-3 See index #: 217
  • Weeds, 1955 (1980) Walter Conrad Muenscher, ISBN# 0-8014-1266-8 See page: 458, 461
  • Weeds, A Golden Guide, 1972 ISBN#0-307-24353-2 See page: 126
  • Weeds of California, 1970, State of California Publications and Documents. See page: 462, 463
  • Weeds of California and other Western States, 2007 (ISBN 13: 978-1-879906-69-3) See Page: 207
  • Weeds of Canada, 1970 Canada Dept. of Ag., Pub. # 948, See page: 158
  • Weeds of Kentucky and Adjacent States, 1991 (ISBN 0-8131-1743-7) See page: 18
  • Weeds of Nebraska and the Great Plains, 1994 (ISBN 0939870-00-4) See page: 128
  • Weeds of Nova Scotia, 1986 (ISBN# 0-88871-063) See page: 24
  • Weeds of Southern Turfgrasses, 1992 Univ. of Florida, Gainesville Publication # SP-79, See page: 94
  • Weeds of the Midwestern United States & Central Canada, University of Georgia 2010, ISBN#0-8203-3506-1 See page: 92
  • Weeds of the North Central States, 1981 Univ. of Illinois, Urbana - Champaign Bulletin # 772, See page: 207
  • Weeds of the Northeast, 1956, Univ. of Delaware Field Manual #1 See species #: 137
  • Weeds of the Northeast, 1997 Cornell University ISBN# 0-8014-8334-4 See page: 118,136
  • Weeds of the Northern United States and Canada, 1964 Montgomery See page: 183
  • Weeds of the South, University of Georgia 2009, ISBN#0-8203-3046-9 See page: 75
  • 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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