Ontario Weeds: Long-spined
Table of Contents
- Other Names
- General Description
- Stems and Roots
- Flowers and Fruit
- Similar Species
- Related Links
Name: Long-spined sandbur, Cenchrus
longispinus (Hack.) Fern.,
Other Names: cenchrus épineux,
Family: Grass Family (Gramineae)
General Description: Annual, reproducing
only by seed.
Photos and Pictures
Long-spined sandbur. A. Plant. B. Leaf-base.
C. Bur enclosing spikelet.
Stem and leaf-base characteristics of a typical grass.
Stems & Roots: Stems mostly 10-60cm
(4-24in.) long, erect or spreading or lying on the ground; leaves
flat or margins inrolled, usually constricted and partially twisted
at the junction with the leaf sheaths, 2-12cm (1-5in.) long, mostly
hairless but rough in one direction; leaf sheaths split with overlapping
margins these margins on young plants membranous and without hair,
but on upper leaf sheaths of older stems membranous and usually
also with few to many hairs 1-2mm (1/25-1/12in.) long; ligule a
fringe of hair mostly less than 1mm (1/25in.) long; there is also
a tuft of short and long (2-3mm, 1/12-1/8in.) hair on each side
of the collar at the junction between blade and sheath; no auricles.
Flowers & Fruit: Inflorescence
a group of spiny burs at the end of each stem; each bur 4-6mm (1/6-¼in.)
long, containing 1 or 2 "seeds," and covered with extremely
sharp spines 2-6mm (1/12-¼in.) long with backward-pointing
barbs which anchor into skin, etc., the whole bur breaking off when
mature. Flowers from August to September.
Habitat: Long-spined sandbur is a
native grass in areas of sandy soil throughout southern Ontario.
Though normally found along sandy beaches, sand dunes, riverbanks
and roadsides, it is becoming a problem in tobacco fields, other
row crops and occasionally in lawns and gardens on sandy soils.
Similar Species: Once the burs have emerged,
Long-spined sandbur cannot be confused with any other grass in Ontario.
Younger plants can be distinguished from most other grasses by the
split sheath with membranous margins, and usually some hair on the
margin, together with the hairy ligule and the tufts of long hair
on either side at the junction between blade and sheath.
... on general Weed
... on weed identification, order OMAFRA
Publication 505: Ontario Weeds
... on weed control, order OMAFRA
Publication 75: Guide To Weed Control
to the Ontario Weeds Gallery |