Botanical Name: Quercus garryana
Common Names: Garry oak, Oregon white oak or Oregon oak
Habitat : Quercus garryana is native to Western N. America – British Columbia to California. It grows on dry prairies and foothills to rocky bluffs.
Quercus garryana is a deciduous drought-tolerant tree, typically of medium height, growing slowly to around 20 m (occasionally as high as 30 m) or as a shrub to 3 to 5 metres (9.8 to 16.4 ft) tall. It has the characteristic oval profile of other oaks when solitary, but is also known to grow in groves close enough together that crowns may form a canopy. The leaves are deciduous, 5–15 cm long and 2–8 cm broad, with 3-7 deep lobes on each side. The flowers are catkins, the fruit a small acorn 2–3 cm (rarely 4 cm) long and 1.5–2 cm broad, with shallow, scaly cups.
It is not frost tender. It is in flower in May, and the seeds ripen in October. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by Wind.Suitable for: medium (loamy) and heavy (clay) soils and can grow in heavy clay soil. Suitable pH: acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil and can tolerate drought. The plant can tolerates strong winds but not maritime exposure.
The Oregon white oak is commonly found in the Willamette Valley hosting the mistletoe Phoradendron flavescens. It is also commonly found hosting galls created by wasps in the family Cynipidae. ‘Oak apples’, green or yellow ball of up to 5 cm in size, are the most spectacular. They are attached to the undersides of leaves. One common species responsible for these galls is Cynips maculipennis. Other species create galls on stems and leaves. Shapes vary from spheres to mushroom-shaped to pencil-shaped.
There are three varieties:
*Quercus garryana var. garryana – tree to 20 (30) m. British Columbia south along the Cascades to the California Coast Ranges.
*Quercus garryana var. breweri – shrub to 5 m; leaves velvety underneath. Siskiyou Mountains.
*Quercus garryana var. semota – shrub to 5 m; leaves not velvety underneath. Sierra Nevada
Landscape Uses:Aggressive surface roots possible, Specimen, Street tree. Prefers a good deep fertile loam which can be on the stiff side. Lime tolerant. Young plants tolerate reasonable levels of side shade. Tolerates moderate exposure, surviving well but being somewhat stunted. Prefers warmer summers than are usually experienced in Britain, trees often grow poorly in this country and fail to properly ripen their wood resulting in frost damage overwinter. A slow-growing and drought tolerant tree, it can live for 500 years. Seed production is cyclic, with a year of high production being followed by 2 – 3 years of lower yields. The tree flowers on new growth produced in spring, the seed ripening in its first year. Intolerant of root disturbance, trees should be planted in their permanent positions whilst young. Hybridizes freely with other members of the genus. Plants in this genus are notably resistant to honey fungus. Special Features: North American native, Inconspicuous flowers or blooms.
Seed – it quickly loses viability if it is allowed to dry out. It can be stored moist and cool overwinter but is best sown as soon as it is ripe in an outdoor seed bed, though it must be protected from mice, squirrels etc. Small quantities of seed can be sown in deep pots in a cold frame. Plants produce a deep taproot and need to be planted out into their permanent positions as soon as possible, in fact seed sown in situ will produce the best trees. Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly.
Edible Parts: Seed.
Edible Uses: Coffee.
Seed – raw or cooked. Up to 25mm long. Up to 32mm long and 25mm wide according to other reports, which also said that it has a sweet taste. The seed is ground into a powder and used in making bread etc, it is a good thickener for soups and stews. The seed has a high content of bitter tannins, these can be leached out by thoroughly washing the dried and ground up seed in water, though many minerals will also be lost. Either the whole seed can be used or the seed can be dried and ground it into a powder. It can take several days or even weeks to properly leach whole seeds, one method was to wrap them in a cloth bag and place them in a stream. Leaching the powder is quicker. A simple taste test can tell when the tannin has been leached. The traditional method of preparing the seed was to bury it in boggy ground overwinter. The germinating seed was dug up in the spring when it would have lost most of its astringency. The roasted seed is a coffee substitute.
Any galls produced on the tree are strongly astringent and can be used in the treatment of haemorrhages, chronic diarrhoea, dysentery etc. A decoction of the bark has been used in the treatment of tuberculosis. An infusion of the plant has been drunk by a mother before her first baby comes. The pounded bark has been rubbed on the abdomen and sides of the mother before her first delivery.
Repellent; Tannin; Wood.
A mulch of the leaves repels slugs, grubs etc, though fresh leaves should not be used as these can inhibit plant growth. Oak galls are excrescences that are sometimes produced in great numbers on the tree and are caused by the activity of the larvae of different insects. The insects live inside these galls, obtaining their nutrient therein. When the insect pupates and leaves, the gall can be used as a rich source of tannin, that can also be used as a dyestuff. Wood – hard, heavy, strong, tough, close grained, durable, easy to split. Used for furniture, cabinet making, general construction etc and also for fence posts and fuel. When used as firewood, garry oak produces 28 million BTUs per cord burned.
Recently the wood, which is similar to that of other white oaks, has been used experimentally in Oregon for creating casks in which to age wine.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.