Invasive Species

"If we want fewer house sparrows and starlings, we do not need to kill them, we need to create an urban landscape in which a richer variety of species can thrive."

Lyanda Lynn Haupt, The Urban Bestiary

I thought about the above quote while I was out harvesting some knapweed the other day. She was talking about birds in urban areas, but the same theory holds true for plants in suburbs, farmland,and the margins like areas around train tracks and roads. Most of the reason this pesky plant survives is because we give it everything it needs to thrive. We want monocultures and grazing land at our disposal, but both of these create the perfect environment for knapweed of all kinds. 

Spotted knapweed is the most common around my neighborhood.  One recommended method to get rid of it over time is to keep mowing it and never let it bloom(this is not advisable for Russian knapweed to my understanding). This stresses the plant and eventually it dies. Since the seeds can be viable for up to ten years one could hose the area with pre emergent, creating an unbalanced situation where nothing can sprout, leaving more room for the knapweed to come up later once the pre emergent has lost its efficacy. Each plant produces 1,000 seeds, there is no way to know you have sprayed each and every one. Our local lupines, when encouraged to grow do beat knapweed to the punch as their roots contain oxalic acid which discourages the knapweed seed to sprout, while local grasses are unaffected and grow right alongside the lupine. A healthy balanced environment creates a situation where the knapweed can't grow.
I do my part by hacking it down and bringing it home and putting it in my steam pot. This scarf was pretreated with steel wool and printed with Arrowleaf Balsamroot (a native wildflower) and spotted knapweed. It is kind of a picture of Eastern Washington all on one piece of fabric.

Spotted knapweed makes a lovely yellow dye on protein fibers with an alum pre-mordant. Don't boil, just simmer. If I remember right I let the plant material soak in the water overnight first.

Here are both plants in all their glory. On silk with an alum pre-mordant. Remember that safety comes first, wear gloves to collect plants in the wild and always steam the fabric bundles outside.

"Spontaneous" plants (weeds) can be a lot of fun and as long as you don't do anything to make the situation worse nobody cares if you come to take them off their hands.