Knapweed Control

KNAPWEEDS
(SPOTTED & DIFFUSE)
CONTROL METHODS

Douglas County Noxious Weed Control provides this information as a courtesy (disclaimer) to those
who are interested in controlling noxious weeds. We recommend a combination of two methods
below (an integrated approach) to effectively control an infestation. If you prefer to have
a Commercial Company take care of your Control needs, you can visit our Contractor's Page
or use any Contractor found in the Yellow Pages.
Equipment may also be available at a local rental store. .

Remember, no matter what method(s) is used, ALL AREAS of the property must be maintained.
These areas include around fences, poles, mounds, holes, hillsides (no matter how steep),
and any other that may require specialized control

CHEMICAL APPLICATION

Note: The below information is derived from the Nebraska Cooperative Extension EC 06-130-D
(HERBICIDE USE IN NEBRASKA). Please consult the individual pesticide label for proper application rates.
Always read and follow label directions and wear the proper Personal Protective Equipment

HERBICIDE*	APPLICATION TIME	REMARKS
2,4-D LV Ester (4L)	Rosette Stage	Use in pastures, roadsides and waste areas.

* A property owner is not limited to these Herbicides only. Other Herbicides may be available, please
consult the individual herbicide label for proper application directions. Herbicides can be found at
area nurseries, retail stores, farm stores, and other landscape centers. For more information on
Herbicides and their uses please check with the Douglas County Extension Service.

MECHANICAL CONTROL

METHOD	TIMING	REMARKS
Mowing	Prior to producing seeds	Mowing will temporarily prevent plants which have reached bud stage from producing seeds. Seed heads will grow back close to the ground producing mature seeds.

BIOLOGICAL CONTROLS

ALL Biological Controls must be approved by the Douglas County Weed Control.

Experiments, using several types of insects which are natural enemies of the Knapweed, are being
conducted to assist in controlling the spread of these plants. Difficulty in obtaining and of
establishing these insects has made biological control a slow, but promising, method of control.
Because of the lack of Knapweed in Douglas County, Douglas County Weed Control will not
approve the use of Biological Controls (insects) on Knapweed.

CONTROL METHOD RECOMMENDATION

Note: Improving the conditions and competition of desirable grasses and vegetation
is the best defense against noxious weeds. Avoiding waste areas, overgrazing, disturbed
ground and proper care of existing vegetation, will aid in keeping noxious weeds away.