This topic has been brought up in the past on more than one occasion. The term native opens up a can of worms that Dave did not want to get into, but I think he said that it was ok to make note of a plants nativity in the comments. If you are looking for a place to find if a plant is native, I would recommend Biota of North America (BONAP)
http://bonap.net/NAPA/Genus/Tr...
