|Wade Bowcutt asks Jeffrey Pettingill to tell him about the differences between Russian, Spotted and Diffuse Knapweeds. Jeffrey notes that it is easy to distinguish Russian Knapweed because it typically produces a lavender colored flower and he points to a few in the field. Another unique feature of this plant is that once it gets pollinated the flower pod closes back up and the seed will stay in the pod for years until something comes by and crushes it and opens the seed up. Other Knapweed seeds blow away in the wind.
He notes another characteristic of the Russian Knapweed is that they are not individual plants like the Diffuse and Spotted. He shows the root of a Russian Knapweed and states that the plant is mostly underground and you will notice at the bottom it is all connected together through what is called rhizomes, or underground stems. He states that if you tried to control this with a disc or a plow, what you would do is shear off all these roots and you would get new plants everywhere there was a broken root.
Jeffrey also notes the Russian Knapweed has very small individual leaves up and down the stem of the plant that distinguish it from other knapweeds.
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