Quercus × macdonaldii
Quercus × macdonaldii, formerly Quercus macdonaldii, with the common names MacDonald's oak and Macdonald oak, is a rare hybrid species of oak in the family Fagaceae. Description 
The tree is between 5 to 15 meters tall, with scaly bark on the trunk. The twigs are gray and tomentose. The leaves are between 4 to 7 centimeters in length, the blades are oblong to obovate, and adaxially glabrous to sparsely hairy. The petioles are between 3 to 10 millimeters. The fruits cup is between 10 to 20 millimeters long and 6 to 10 millimeters deep. The nuts are between 20 to 35 millimeters long and conic-oblong or ovoid. The flowering time is between the months of March to May. Distribution
The tree is endemic to the California Channel Islands, on Santa Cruz Island, Santa Rosa Island, and Santa Catalina Island, in Southern California. It is found in chaparral and woodlands habitats in canyons and slopes below . Taxonomy
The plant was reclassified as Quercus × macdonaldii, a naturally occurring hybrid of Quercus lobata and Quercus pacifica, or possibly other oak species. Both parents are placed in section Quercus. It is considered a species by Greene but derived from hybrids involving Quercus pacifica, Quercus lobata, and possibly others. See also
California chaparral and woodlands ecoregion
California coastal sage and chaparral sub-ecoregion

References

External links
 Jepson eFlora treatment of Quercus × macdonaldii
 USDA Plants Profile for Quercus × macdonaldii  [berberidifolia × lobata]  (MacDonald oak)
  Calflora Database: Quercus × macdonaldii (MacDonald's oak, MacDonald oak)

macdonaldii
Endemic flora of California
Natural history of the Channel Islands of California
Natural history of the California chaparral and woodlands
Natural history of Los Angeles County, California
Trees of the Southwestern United States
Hybrid plants
Taxonomy articles created by Polbot