Q. What makes a plant invasive, and why are they considered harmful? Whenever we hear about invasive species, we usually think about pest insects or arthropods such as Argentine ants or fruit flies.

Editor’s note: This article is being republished courtesy of cascadepbs.org. Skye Pelliccia knows an invasive plant when she sees one. “[They] could be [in] a development area, roadsides, somewhere ...