Concolor fir, also known as white fir, is native to the mountains of western North America. The tree grows in an almost perfect pyramidal Christmas tree shape when young (and is often grown commercially as a Christmas tree). At maturity the tree develops a dome-like crown. The short, flat, soft needles are silvery blue-green both above and below, although the undersides may have a whitish bloom. Concolor fir is a fairly slow-growing, drought-resistant tree. It does best in deep, rich and well-drained soils. Avoid heavy clay and wet spots, such as near over-irrigated lawns. This fir may need some protection on very windy, exposed sites.