Key identifying traits
- Flowers are small yellow and
grow along one side of the stem
- Stems and leaves are covered
with bristly hair
- The tips of the plants are
curled into a “fiddleneck” or scorpion tail appearance
- Fruits form in 4 nutlets,
each containing one seed
- Plants will grow to 1 - 2 ˝’
tall
- When they begin to dry,
hairs are brittle and stick into skin
Biology and ecology
- An annual reproducing from
seed
- Plants are toxic to horses,
cattle and pigs when they are green or dry in hay, potentially
causing severe liver damage
- This plant is a native
of California and Oregon now widespread across the U.S.
- Commonly seen in barnyards,
corrals, newly planted fields, and overgrazed areas
Control
Prevention – Learn to identify
plants; check areas where hay is fed or animals are held, areas where
soil is disturbed or overgrazed
Biological – No known biological
control
Cultural – Does not compete well
with a good grass or perennial plant stand
Mechanical – Cultivation works
good as well as hand pulling small areas, mowing before seed production
can kill many of the plants
Chemical – Difficult due to the hairs
and must be done before seed production: refer to the
PNW Weed Management Handbook for specific chemical recommendations
in various sites |
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