|
Key identifying traits
A rounded, bushy, much branched appearance
Stems are usually red or purple striped, even more so as the growing
season wears on
Leaves are alternate-the first are long, string like and soft, with
later leaves short, scale-like and tipped with a stiff spine
Inconspicuous green flowers borne in axils of upper leaves, each
with a pair of spiny bracts
Biology and ecology
- An annual, ½ to 3 feet tall reproducing by seed
- Seeds spread as mature plants break off at the ground and are
scattered by wind as tumbleweeds
- Rapid germination and establishment occur after only brief and
limited amounts of precipitation
- Native to Russia and introduced in late 1800s, has become one of
the most common and troublesome weeds in drier regions of the U.S.
- Well adapted to cultivated dryland agriculture and along roads and
in other disturbed sites
Control
Prevention – Learn to
identify plants; know your property, be careful of seeds in fill
material and avoid bare soil where the seeds can start
Biological – None known at this time
Cultural – Healthy plant communities help greatly to reduce
likelihood of establishment
Mechanical – Cutting, pulling and digging can work on small
infestations if repeated as necessary-in cultivated fields the timing of
tillage and the crop rotation can be used to greatly reduce the problem
Chemical –
Difficult to control due to timing of germination and nature of the
plant;
refer to the
PNW Weed Management Handbook for specific chemical recommendations |
red stem with "thorns"
|
