| Description |
Quercus garryana, a native deciduous tree up to 30 m tall throughout much of its range in the Pacific Northwest, has an open, rounded crown. The mature bark is brownish gray and shallowly fissured in a checker-like pattern. Leaves are oblong to obovate, 8-15 cm long, and deeply lobed (5-7 rounded lobes). The upper surfaces are shiny and dark green, but the lower
surfaces are pale green. Like all oaks, Oregon oak is
monoecious and wind-pollinated. The acorn cups are
composed of thick, tubercled scales. The one-seeded
nuts are 2-3 cm long, ovoid, and mature in one year.
Flowering takes place from March to May. Fruits
mature between August and November.
Adaptation: Oregon oak is best developed as a tree on
slopes and valleys below 1500 m where annual
rainfall exceeds 30 inches. The range in climate is
considerable, extending from the relatively cool,
moist Fraser Valley of British Columbia to the
summer-dry Coast Ranges north of San Francisco
and the foothills of the Sierra Nevada in California. It is tolerant of freezing conditions and also has a broad tolerance of substrates, which vary from rocky, thin soils of ridges to the deep loams and clays of valley bottoms.
Seed Preparation: Oak seeds do not store well and consequently seeds should be planted soon after maturity. Nuts are considered ripe when they separate freely from the acorn cap and fall from the tree. Care should be taken to collect local fruits, because they may be adapted to local environmental conditions. Viable nuts may be green to brown, and have unblemished walls. Nuts with discoloration or sticky exudates, and small holes caused by insect larvae, should be discarded.
Direct Seeding: Seeds may be planted at the
beginning of the winter. Once the site is chosen,
prepare holes that are 10 inches in diameter and 4-5
inches deep. One gram of a slow-release fertilizer
should be placed in the bottom and covered by a
small amount of soil. Place 6-10 acorns in each hole
at a depth of 1-2 inches. Rodents or birds should use
temporary enclosures to minimize herbivory. A
simple enclosure can be constructed from a one-quart
plastic dairy container with the bottom removed and
a metal screen attached. Towards the end of the first
season, seedlings should be thinned to 2 or 3 per hole
and to one seedling by the second season.
Supplemental watering may be necessary if a drought
of 6 weeks or more occurs during the spring.
Container Planting: Seeds may be planted in onegallon containers, using well-drained potting soil that
includes slow-release fertilizer. Tapered plastic
planting tubes, with a volume of 10 cubic inches,
may also be used. Seeds should be planted 1-2
inches deep and the soil kept moist and aerated.
Seedlings should be transplanted as soon as the first
leaves open and become firm, which generally occurs
in spring. Planting holes should be at least twice as
wide and deep as the container. Seedlings may
require watering every 2-3 weeks during the first
season. Care should be taken to weed and mulch
around young plants until they are 6-10 inches tall.
Citation:
USDA, NRCS. 2022. The PLANTS Database (http://plants.usda.gov, 07/23/2022). National Plant Data Team, Greensboro, NC USA.
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