Ontario Weeds: Cleavers
Excerpt from Publication 505, Ontario Weeds, Order this publication
Table of Contents
- Other Names
- General Description
- Stems and Roots
- Flowers and Fruit
- Similar Species
- Related Links
Cleavers, showing backward- or downward-pointing hairs on stems and whorled leaves.
Cleavers. A. Lower and upper parts of a mature plant. B. Portion of stem enlarged to show the backward-pointing bristles.
Stems & Roots: Stems weak or
reclining, 10-121cm (4-48in.) long, square in cross-section with
strongly ribbed corners, with very short, downward- or backward-pointing,
firm, hair-like, curved bristles; leaves usually 3 to 8 in a whorl,
linear, tapering at the base, mostly 1-8cm (2/5-3-2/5in.) long,
with bristles at the pointed tip, somewhat hairy on both surfaces
and with many very short, backward-pointing bristles on the margins.
These tiny hook-like bristles on stems and leaves cause them to
cling together in masses and to cling to clothing, skin or fur,
hence the common name, "cleavers."
Flowers & Fruit: Inflorescence mostly 1- to 5-flowered; flowers very small and soon replaced by the small spherical fruits; fruits bristly, 1.5-4mm (1/16-1/6in.) in diameter. Flowers from May to August.
Habitat: Cleavers is found in southern Ontario in woods, meadows, compost heaps, gardens and fields, and along roadsides and riverbanks.
Similar Species: It is distinguished by its square, weak, clinging stems, its bristle-tipped leaves that also cling with backward-pointing bristles on the margins, and all leaves arranged in whorls of 3 to 8 at each node of the stem.
For more information:
Toll Free: 1-877-424-1300