Native to a huge expanse of the cool northern woodlands of North America, the white paper birch (Betula papyrifera) grows best in moist, sandy or silty soils. A landscape staple in USDA hardiness zones 2 through 6, golden yellow fall leaves drop away to reveal unimpeded views to the stark white bark that looks most picturesque with any evergreen tree background.
Although botanists agree that the white paper birch is known universally as Betula papyrifera, some literature mentions six naturally occuring variations of this species across its expansive native range in North America. The physical characteristics distinguishing these natural varieties remain minute if not impossible for the untrained eye, but the Flora of North American taxonomic database suggest the differences may be caused by environmental growing conditions. Different climates, soil fertility and genetic isolation of a small population act to intensify any small-scale differences. As such, rarely do you see mention of the natural varieties in discussions of white paper birches for ornamental garden selection and use.
White paper birch hybridizes naturally with many other native North American birch species, leading to many trees with ornamental features similar to white paper birch. According to the U.S. Forest Service, hybrid crosses with yellow (Betula alleghaniensis), sweet (Betula lenta), and river (Betula nigra) birch have not been named. Blue birch (Betula x caerulea) is thought to be a hybrid between gray birch and white paper birch. The variety cordifolia is perhaps the hybrid of paper and yellow birch. Named hybrids resulting from crosses between paper birch and shrub or small tree species include Yukon birch, horne birch, Sandberg birch and Andrews birch.
Two man-selected cultivated varieties, cultivars, of white paper birch exist. 'Chickadee' attains a narrower canopy than the wild species while 'Snowy' grows quickly as a sapling and demonstrates improved resistance to birch borer insect pests. Patented selection 'Rensi', sold under the trademark name of Renaissance Reflection®, shows excellent resistance to summertime heat and borer insects, too. 'Uensi', sold as Renaissance Upright®, is similar to 'Rensi' but becomes narrower in habit at maturity. 'Varen', sold as Prairie Dream®, develops very dark green leaves and immaculate white bark with exceptional resistance to bronze birch borer and leaf miner pests.