Adams County
CO Noxious Weeds

Home > CO Noxious Weeds > Spotted Knapweed

Spotted Knapweed

Management

Cultural, Mechanical, & Biological Management

Spotted Knapweed Control

These methods of control are similar to those for diffuse and Russian knapweed.

 

Spotted knapweed bractsHerbicide Control

Some herbicides are labeled for control of spotted knapweed. Those that can be used independently or in combination with each other are: Picloram (Tordon), clopyralid (Stinger), dicamba (Banvel), 2,4-D, and a premix of clopyralid and 2,4-D (Curtail). Picloram has been found to be most effective. 2,4-D,when used alone, results in poor control.

 

 

Herbicide
Rate (per acre)
Application Time
Remarks

Tordon 22K

1 pt.

Apply in spring prior to stem elongation and/or to rosettes in the fall.

n/a

Banvel +

2,4-D Amine

1 pt. +

1 pt.

Apply in spring prior to stem elongation and/or to rosettes in the fall.

n/a

Curtail

2 qts.

Apply in spring after majority of basal leaves emerged to pre-bud stage.

Apply in enough total spray volume to ensure good coverage.

Read the label to insure the herbicide is labeled for your application site.


 

Disclaimer | EEO | Ask an Expert | Webmaster - Last updated 9-3-08

Extension Home | CSU Home

CSU Extension Home