Scientific Family
Asteraceae
Other common names
horseweed
Plant type
Forbs and Subshrubs
Origin
Introduced
Lifecycle
Biennial or annual
Height
Up to 7 feet
Riparian
No
A common very vertical, tall weed. Not branched except for multiple flowering stems spreading outward near the top of the plant. Considered invasive in some areas of the U.S. Heights reported as much as 7 feet.
Tall annual herb, many branched leafy stems with alternate simple leaves. Stem and branches covered with short, bristly hairs. Flower heads 3 to 5 mm across, crowded in branched terminal clusters, composed of white ray and yellow disc florets.
Habitat
Found in pastures, fields, waste areas and along roadsides. Grows in many different soils.
Plant Community
Disturbed Areas
Low elevation
1000
High elevation
8000
Flower Characteristics
Has many inconspicuous flowers forming small composite flower heads about 1/8 inch across. Composite heads have white ray
flowers and yellow disc flowers.
Flower color
White and yellow
Flower shape
Daisy or dandelion-like
Tubular
No
First bloom month
July
Last bloom month
October
Flower clusters
Other
Leaf and Stem Characteristics
Leaves alternate around the main vertical stem. To 4 inches long and 1/2 inch wide. Has a few white hairs along the edge.
Leaf type
Simple
Leaf color
Green
Leaf shape
Narrow
Leaf margin
Smooth
Leaves clasp
No
Leaf hairs
Leaves & stems
Spines
No
Fruit and Seed Characteristics
Elliptic in shape.
Fruit type
Achene
Fruit color
Brown