Californian White Oak, Valley oak
Quercus lobata

Family: Fagaceae

What it is like

Bloom Color: Brown. Main Bloom Time: Early spring, Late spring, Mid spring. Form: Oval, Rounded.

Quercus lobata is a deciduous Tree growing to 30 m (98ft 5in) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 7 and is not frost tender. The species is monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and is pollinated by Wind. Suitable for: medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil. The plant can tolerates strong winds but not maritime exposure.

Height (m): 30

Where it is found

Fertile lowlands in deep rich soils in the valleys of W. California between the Sierra Nevada and the coast.

South-western N. America - California.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 2

Seed - cooked. A staple food for several native North American Indian tribes. Quite large, it is up to 5cm long and 15mm wide. The seed of this species is sweet and low in tannin and needs little if any leeching. Any bitter tannins can be leached out by thoroughly washing the dried and ground up seed in water, though many minerals will also be lost. 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 seed can be roasted and then eaten, its taste is something like a cross between sunflower seeds and popcorn. The seed can also be ground into a powder and used in making bread etc. Roasted seed is a coffee substitute.

Seed: includes nuts, cereals, peas and beans.

Coffee: the various substitutes that can be used instead of coffee.

Medicine

Rating: 2

Any galls produced on the tree are strongly astringent and can be used in the treatment of haemorrhages, chronic diarrhoea, dysentery etc. A poultice of the ground galls and salt has been used as a treatment for burns, sores and cuts. A decoction of the bark has been used as a cough medicine and a treatment for diarrhoea. The pulverized bark has been used as a dusting powder to dry up running sores, it is particularly useful for babies with sore umbilicus.

Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.

Dysentery: Used in treating dysentery - an infection of the intestines that causes diarrhoea containing blood or mucus.

Poultice: A moist, usually warm or hot, mass of plant material applied to the skin in the treatment of burns etc.

Salve: Soothes and heals damaged skin.

Other

Rating: 2

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. The acorn meal has been used to mend cracks in clay pots. Wood - hard and fine grained but brittle and weak. Of no commercial value, it is used only for fuel.

Adhesive: Glues.

Fuel: Usually wood, plant materials that have been mentioned as being a good fuel.

Repellent: Plants that are said to deter but not necessarily kill various mammals, birds, insects etc.

Tannin: An astringent substance obtaied from plants, it is used medicinally, as a dye and mordant, stabilizer in pesticide etc.

Wood: A list of the trees and shrubs that are noted for having useful wood.

How it is grown

Landscape Uses:Aggressive surface roots possible, Specimen, Street tree. Prefers a good deep fertile loam which can be on the stiff side. 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 fairly long-lived tree in the wild, with specimens 300 - 400 years old recorded. It is very slow growing in Britain, but there is a specimen at Kew that was 27 metres tall in 1988. The tree flowers on new growth produced in spring, the seed ripening in its first year. Good crops are produced in the wild every 2 - 3 years. 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.

Propagating it: 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.

Best place to grow: Woodland Garden Canopy;

Habit: Tree

Hardiness: 7-11

Growth: Slow

Soil: Medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Synonyms

Q. hindsii.