By The Blaine Bug Crew
When looking out your kitchen window in the early morning hours you may notice a pink spiny flower that you don’t recall planting. As the Blaine County Bug Crew, we are here to enlighten you about this mysterious plant. This flower-bearing plant is known as spotted knapweed and is commonly found in our valley during this time of year.
Spotted knapweed is a short-lived perennial noxious weed. This weed can produce up to 25,000 seeds, which are brown or black. The seeds can live in the soil for up to eight years. Spotted knapweed is easily recognizable by the pinkish-purple flowers that bloom from July to October. The flower head bracts are black-tipped, giving the plant its characteristic spotted appearance. Stems are typically 2-4 feet tall with lower leaves that are deeply lobed and upper leaves that are more linear. Spotted knapweed ranges from moist rangeland habitats to abandoned areas.
As an attempt to decrease the frequency of the presence of this noxious weed, we, The Blaine County Bug Crew, use the insect Cyphocleonus achates as a predator to target populations. This root-burrowing weevil lays its eggs in the roots of the knapweed. The larvae then feed on the vascular tissue to reduce the plant’s density and vitality. The adults emerge from the roots between June and September to feed on the leaves and lay eggs of their own.
If you notice your gardens, fields, or favorite natural habitat being threatened by this plant, please contact the Blaine County Weed Department at (208) 788-5543.