Thank you for your question, Barbara.  This is a non-native species, which is native in China.  It is an 'aggressive' annual plant, which is considered invasive in some Southeastern states.  You can read about it here:  http://www.gardening.cornell.edu/homegardening/sceneb320.html

Its failure to appear on invasive plant lists may be just a factor of its neither being sold nor classified.  So as not to "promote" it to a "bad plant" status, I suggest you find another species to grow.  Here is a publication with some ideas:  https://www.oregonmetro.gov/native-plants-willamette-valley-yards-booklet
Good luck!