Rocky Mountain White Oak
Native to (or naturalized in) Oregon:
- Broadleaf deciduous tree or shrub, height is variable, from matted shrubs to trees 50 ft (15 m) high, stoloniferous and thicket-forming, twigs at first gray-yellow pubescent, later olive brown. Leaves alternate, simple, elliptic to obovate or oblong, 7-12 cm long, with 3-6 oblique lobes, uneven, sinuses (clefts) shallow to deep (sometimes almost to the midrib), base wedge-shaped to rounded, margins entire or coarsely toothed, dull green above, light gray-green below, petiole 1-2 cm long; foliage turns yellow, orange and red in fall. Separate male and female catkins produced on the same tree on the current year's growth. The female catkins are very small and borne in the leaf axils. Fruit (acorns) solitary or paired, near sessile, egg-shaped, 1.5-2 cm long, cup encloses 1/4 to 1/2 of the nut.
- Sun. Adaptable to a wide range of soils and moisture levels. Reportedly best in coarse, well-drained and slightly alkaline soil.
- Hardy to USDA Zone 4 Native to the Southwestern USA (Arizona, Utah, Colorado, New Mexico), northwestern Mexico, above 5000 ft elevation (~1500 m) Rocky Mountains from Utah and Wyoming to Mexico. Can be grown in containers and bonsai.
- gambelii: after William Gambel, 19th century Western plant collector and Assistant Curator of the National Academy of Sciences (1823-1849). He discovered his namesake oak on the upper Rio Grande in 1840. His friend and mentor, the well known English naturalist, Thomas Nuttall, named the oak to honor him in 1848, a year before Gambel died of typhoid in the California at the age of 27.
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