Description:
Kochia
is an annual plant that reproduces from seeds. It has a deep
taproot. The erect, much-branched stems are three to seven feet
long, smooth below but usually hairy above. The alternate, simple
leaves are pubescent to nearly glabrous, one to two inches long,
lanceolate to linear with hairy margins, and without petioles.
The small green flowers lack petals and are found in clusters
in the axils of the upper leaves and in terminal spikes. The
brown flattened seeds are about 1/16 inch long and grooved on
each side.
In the Great Plains, where kochia is widespread,
it is considered a serious pest of late-maturing crops such as
sorghum, soybeans, and sugarbeets. It is also a problem in the
fallow portion of the cereal-fallow cropping systems. Kochia
is an effective competitor for light, nutrients, and soil moisture,
and can reduce crop yield. There is a high variation in the flowering
time of populations of kochia. Early populations can become a
problem in cool-seasoned cereal crops.
- Mechanical: Early
tillage in the spring gives good control of the kochia seedlings.
Mowing or slashing the plants before flowering is effective
in reducing seed production.
- Biological:
Not Known
- Herbicide: Research
has shown that triazine resistant biotypes were more susceptible
to 2,4-D ester than triazine susceptible biotypes. There are
also biotypes resistant to 2,4-D or Banvel (dicamba). It is
suggested that rotating herbicides would reduce the possibility
of an increase in the proportion of plants tolerant to 2,4-D
or Banvel.
For More Information:
Detailed information about Kochia is available at the Washington
State Noxious Weed Control Board Web Site. |
