SNOW-ON-THE-MOUNTAIN, otherwise known as Euphorbia Marginata is a beautiful plant, but much as my husband loves prairie wildflowers, he refers to this one as a weed. We had three huge plants come up volunteer last summer and then go to seed, so this year Ken has been yanking the little sprouts as fast as they pop up. But a few managed to sneak by and I think I've persuaded him to let them stay for a few weeks as long as I promise to eradicate them before they develop pods and self-seed.