Eating is believing.
Japanese Knotweed is an introduced species to our ecosystem. It is a powerful plant with a root system strong enough to buckle sidewalks. It has crept onto our farm from who-knows-where about five years ago. Rather than shake our fists, we pulled out our harvest knives and began taste testing the stuff. Celebrated in Japan - it really is quite delicious.
Here is a link to learn more about the plant and some links to recipes.