I don't know how invasive it is. I've seen this growing from Austin and south, south east and south west from there, but it's always either been in a yard or a spot that's been more or less abandoned where it has been left to do it's own thing. I've never seen it growing outside of those situations where it had originally clearly been planted and cultivated. To me an invasive plant is one that moves and spreads in all kinds of places. Honeysuckle along the banks of a stream, for instance. Or Kudzu in the south. I think for them to be considered invasive, they must be introduced plants which are not native. To me mesquite is an invasive plant, but since it's a native I don't think it's classified as invasive. Remove established trees and disturb the shrubs and grassland in my area and those plants won't return easily because mesquite will move in and take over. To me invasive has to do with the behavior of a plant. If you are finding it coming up with no discernible source, then that is probably invasive behavior. On the other hand, if you haven't been seeing it in a lot of places, then it may not be rampantly invasive. Sure looks nice when it blooms.