An old Chinese idiom says "南橘北枳“, means orange is good in Southern China, but if you move orange trees to North, its fruits become hard and no taste at all. Why? Because environment changes. Kudzu is a good plant in China, maybe you have watched "One bite in China", I can't remember which season, but I remember in one place in Guangdong Province, they cook roots of Kudzu with pork, it looks like really good. However, good guy Kudzu becomes a bad boy in North America. Please see this report from a local newspaper in St. Louis: http://www.stltoday.com/news/local/metro/research-on-vine-that-ate-the-south-is-under-way/article_b99b6cbb-0f57-54e2-8ae3-c8ce869828a8.html
This is the first time I am in an English newspaper!