Stevens County Noxious Weed Control
Board This web site will help
you identify & control noxious weeds. Conventional & biological control
(BioControl) information and photographs are here. Maps & related
information are included.
Leaves are oblong, alternate & deeply lobed; basal leaves are
usually purplish underneath, 1-4" long
The stem of the plant is hollow
Seeds are spindle shaped and tan having a "parachute"
similar to the dandelion
Entire plant is hairless-distinguishing it from other groundsels
Biology and ecology
Annual, winter annual or (rarely) biennial, reproducing by seed
only
One plant can produce as many as 1,000,000 seeds during one
growing season
Groundsel is a native of Europe
Toxic primarily to cattle and horses; sheep have a much higher
tolerance
It has been known to show herbicide resistance
It can germinate in a wide range of temperatures and starts
blooming early in the season
Control
Prevention –
Do not let weeds
produce seed, do not buy contaminated feed or seed
Biological – Larvae of the cinnabar moth will eat Groundsel but
are only present in June through August, research is being done on a
rust fungus
Cultural – Cultivation kills plants and effective if done
before going to seed
Mechanical – Cutting will help if done often and before any
seed is produced
Chemical – Several effective but may require repeat treatments;
be sure to use herbicides with different mode of action every few years.
The
PNW Weed Management Handbook does not have this weed listed for
control recommendations
seedling
Where found –
No
known large infestations in Stevens County to date, but may be found
along roadsides, parking lots, gardens and waste areas.
