Ontario Weeds: Black eyed susan
Excerpt from Publication 505, Ontario Weeds,
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Table of Contents
- Other Names
- General Description
- Stems and Leaves
- Flowers and Fruit
- Similar Species
- For more information...
Other Names: Coneflower, Yellow-daisy, rudbeckie herissée, marguerite jaune, marguerite orangée
Family: Composite or Aster Family (Compositae)
General Description: Perennial or sometimes biennial, reproducing only by seed. Photos and Pictures
Black eyed susan.
Stems & Leaves: Stems are erect,
30 -100 cm (12 - 40 in.) high, single or with a few branches in
the upper parts, more or less rough-hairy throughout. Leaves are
alternate (1 per node); lower leaves long-elliptic, tapering to
a long stalk (a); upper leaves (b) narrow, stalkless, smooth-margined
or somewhat coarsely toothed; all leaves rough-hairy and usually
Flowers & Fruit: Flower heads large and showy at the ends of long, thin, erect branches, 2.5 -7.5 cm (1 -3 in.) in diameter with ray florets (c) orange to orange-yellow and spreading like spokes of a wheel; disk florets (d) dark purple or blackish, individually very small and tightly packed on a conic receptacle forming a prominent, hard, dark, raised centre in the head, like the hub of a wheel; seeds black, 4-angled with fine lengthwise lines. Flowers from mid-June to September.
Habitat: Black-eyed Susan is a native plant in the Great Plains but was introduced into Ontario and has spread aggressively throughout the province in meadows, pastures, edges of woods, river valleys, lakeshores and roadsides, usually in coarse-textured soils.
Similar Species: It is distinguished by its long-elliptic, rough-hairy leaves, and showy, long-stemmed flower heads with bright yellow ray florets and dark purplish to blackish disk florets.
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