This is really a plant called Desert Broom when it has gone to seed. The seeds are like cattails and cover the ground just like snow. If you happen to bump into the bush, the seeds will swirl around like dust or, if you use your imagination, like snow. The plant is a rather invasive weed and will grow anywhere there is enough water. We are always pulling out the smaller versions of this plant from flower beds and gardens. Despite its shortcomings it is a pretty plant.