Beautiful Invasions, Part II: The Generalized Invasion Curve
Reading about scotch broom as I drove away from my wedding was the first time I explicitly remember being able to identify an invasive plant, though I don’t remember wondering what the term meant, so I must have heard it somewhere before. Himalayan blackberry was the next I became intimately familiar with, after buying a few acres and more than a few blackberry patches in the summer of 2020. In King County, the most populous county in Washington state, and the one where Seattle is located, Himalayan blackberries are classified as a class C noxious weed, along with dozens of other species. Noxious weeds are
non-native plants that, once established, are highly destructive, competitive and difficult to control. They have economic and ecological impacts and are very difficult to manage once they get established. Some are toxic or a public health threat to humans and animals, others destroy native and beneficial plant communities.
To be Class C just means that they are so widespread that control is effectively impossible and therefore not required. It’s a surrender, an acknowledgement that humans are not capable of modifying a landscape in any way they see fit after all, at least not without effort or expense beyond what would be gained. Earlier in a plant’s uninvited spread…
