I have three spartium junceum (Spanish broom). One has been growing in my Vancouver Island garden for several years. There is a lot of dieback after the winter, often two-thirds or more of the plant. Last year a couple of seedlings sprouted for the first time, so I now have three bushes. The fragrance is divine. I read that in some places, this is considered a noxious plant. I want to be a good steward of the environment: should I remove all three and put them in the trash?