Quercus marilandica
Common name: 
Blackjack Oak
Jack Oak
Pronunciation: 
KWER-kus mar-i-LAN-di-ka
Family: 
Fagaceae
Genus: 
Type: 
Broadleaf
Native to (or naturalized in) Oregon: 
No
  • Deciduous scrubby tree, may reach 30-40 ft (9-12 m) tall, rarely 70-90 ft (21-27 m), stout branches, often contorted, rounded or irregular outline, often a short trunk.  Bark dark brown to blackish, deeply divided into nearly square plates 2.5-7.5 cm long.  Leaves alternate, simple, thick, firm, roughly triangular, 15-17 cm long, broadly obovate, shallowy 3 or rarely 5-lobed at the very broad apex, margin entire or sparenly toothed, narrow base rounded or cordate, dark, glossy yellow-green above, brownish pubescence below; fall color brown or yellow, remain attached well into winter.  Fruit (acorn) solitary or in pairs, nut rounded at both ends, enclosed 1/3 to 2/3 its length by a turbinate, light brown cup.
  • Sun to light shade.  Often found on soil of poor quality.
  • Hardy to USDA Zone 6      Native range from New York to Iowa and south to Florida and Texas.
  • marilandica: of Maryland 
  • Oregon State Univ., North Willamette Research and Extension Center, Aurora
Click image to enlarge
  • plant habit, small tree

    plant habit, small tree

  • leaves

    leaves

  • leaf

    leaf

  • leaves

    leaves