garryana – refers to Nicholas Garry, Deputy Governor of the Hudson’s Bay Company, who helped botanist and explorer David Douglas during his travels in the PNW

Native range: West Coast of US

Leaves:

• alternate
• simple
• pinnately lobed with 5 to 9 irregular rounded lobes
• darker green above
• lighter green and pubescent below

Flowers:

• monoecious
• male flowers borne in hanging catkins
• female flowers borne in small clusters, appearing with the leaves

Fruit:

• acorn, 2–3 cm. long
• ovoid to sub-globose (nearly spherical)
• solitary or paired acorns on current year’s growth
• involucre hardens into a shallow cup, up to 2 cm broad and 1 cm deep, with rough surface that covers 1/3 the acorn

Other characteristics:

• deciduous tree
• up to 75 ft. but often short and crooked in rocky habitats
• bark light gray with thick furrows and ridge
• branches somewhat twisted and gnarled

Relevant info:

• acorns eaten by Salish peoples of Puget Sound region after soaking to leach out the bitter tannins
• losses of Garry oak woodlands range from 85–95% in the Pacific NW
  • primarily a result of European settlers that suppressed fires, altered land use, and introduced non-native species and heavy grazing

Ecology & Adaptations:

• west of the Cascades, Vancouver Island to California
• eastern foothills of the Cascades from Kittitas County south to the Columbia River
• found in dry prairies and foothills to rocky bluffs
• wooded slopes and montane coniferous forests
• sometimes on deep, well-drained soil
• low elevations (0–800 m.)
• pollinated by wind
• seed dispersal:
  • Douglas’s squirrels carry acorns ~30 ft. before burying them
  • Steller’s jays typically carried acorns 1,000–1,300 ft. (300–400 m.) into conifer-dominated sites before dropping or consuming then
  • Lewis’s woodpeckers often transported acorns 100–200 ft. (30–50 m.) into Oregon white oak- or western juniper (Juniperus occidentalis)-dominated habitats before dropping or consuming them
• vegetative regeneration & reproduction:
  • re-sprouts from roots, root crown and epicormic buds beneath bark
  • root and/or root crown sprouts are common following fire or cutting
  • epicormic sprouts occur following disturbance and canopy release from shading
• fire adaptation:
  • persistence of Oregon white oak communities is dependent on periodic fire
  • Native Americans maintained open Oregon white oak stands through frequent fall burning
• succession:
  • both a pioneer and a disturbance “climax” species
  • often the first tree “invader” on prairies, but without periodic disturbance (fire) it is replaced by conifers
• herbivory defense – tannins in leaves and acorns inhibit digestion in herbivores by interfering with the actions of enzymes involved with breaking down proteins