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Additional Diffuse Kna weed Non -Chemical Control Information Diffuse knapweed response to treatments may be impacted by environmental conditions and the type of treatment utilized. Grazing control: Diffuse knapweed seed production can be reduced *A&% when grazed during the bolting stage for 10 days, wait 14 days then graze for an additional 10 days. Although grazing diffuse knapweed fh can reduce seed production, grazing can also cause diffuse knapweed to become a short-lived perennial. When grazing is stopped, populations often return to their former levels. Pulling or Digging: Pulling or digging requires a commitment of at least 12 years to ensure that removal of new seedlings and re -growth is done before they reestablish. Years one to three of a pulling or digging program will involve intensive removal. During year's four to six, there should be a decrease in diffuse knapweed numbers and the work will be noticeably easier. Pulling or digging of diffuse knapweed is best done in the spring during the rosette or early bud stage, before the flowers appear. Hopefully, the soils will be moist to allow for easier removal. The roots can extend a few feet into the soil. It is important to pull or dig up the entire taproot. Otherwise, the diffuse knapweed may re -grow. Keep in mind that some workers may suffer from allergic reactions while touching diffuse knapweed and inhaling pollen. M_ owing: Diffuse knapweed is persistent. Mowing leaves part of the plant untouched. This part of the plant will still produce flowers. The plant will just be shorter than the mower height and will act more like a perennial plant than a biennial plant. In some cases, diffuse knapweed densities may increase after a single mowing. Burning or Flaming: Normal fires are typically not Iong enough or hot enough to destroy diffuse knapweed seeds. A monitored controlled burn can potentially help control diffuse knapweed if the fire has adequate intensity. It is not easy to find good fuel circumstances to carry a continuous fire that will cause significant injury to the diffuse knapweed without hurting the beneficial vegetation occurring in the infestation. Diffuse knapweed is not very flammable and most areas do not contain enough fuel necessary for the fire. This results in low ' temperature fires with patchy and irregular burns. Even if the surface area of the plant is killed, diffuse knapweed can often re -grow from its root reserves. ' Apropane-fueled weed burner can be utilized to quickly burn the foliage of young diffuse knapweed rosettes. The flame sears the plant, raises the temperature of the cells, this causes the cells to rupture. The diffuse knapweed plant will then dehydrate and expire within a few hours. Flaming is done on green plants; not on dead foliage. Plants can be seared at any time before flowering. Flaming can be useful in clearing small areas.