Quercus Sp. - Oak

Fagaceae - Oak Family [E-flora]

± 600 species: northern hemisphere, to northern South America, India. (Latin: ancient name for oak) [Manos et al. 1999 Molec Phylogen Evol 12:333–349] Many named hybrids; those (3) treated here form widespread populations; most others occur as single individuals, and some but not all of these are mentioned here, under the first parent treated (alphabetically). Reproduction of many species declining due to habitat degradation or loss as well as disease.
Unabridged references: [Manos, P. S., Doyle, J. J., & Nixon, K. C. 1999. Phylogeny, biogeography, and processes of molecular differentiation of Quercus subgenus Quercus (Fagaceae). Molec Phylogen Evol 12: 333–349.][Jepson2012]

Local Species;

  1. Quercus garryana - Garry oak [TSFTK][PCBC][E-flora]
  2. Quercus robur - English oak [E-flora]
[E-flora] [E-flora]

 

Quercus garryana - Garry Oak

"Garry oak (Quercus garryana) ecosystems are among the most endangered in Canada. Only an estimated 1–5% of the 1850s distribution remains in a near-natural state, providing habitat for more than 100 species considered at risk either nationally or provincially. Although habitat fragmentation and isolation threaten the long-term viability of Garry oak–associated species, all habitat remnants have been degraded by exotic species of plants and animals, and many suffer from the effects of fire suppression." [Apostol RPNW]

Description

Hazards

Food Uses

Other Uses

Medicinal Uses

Nutritional

Cultivation

"Lime tolerant (188). Young plants tolerate reasonable levels of side shade(200). Tolerates moderate exposure, surviving well but being somewhat stunted(200).... A slow-growing and drought tolerant tree(188, 229), it can live for 500 years(229). Seed production is cyclic, with a year of high production being followed by 2 - 3 years of lower yields(229). The tree flowers on new growth produced in spring, the seed ripening in its first year(200, 229). Intolerant of root disturbance, trees should be planted in their permanent positions whilst young(11). Hybridizes freely with other members of the genus(200). Plants in this genus are notably resistant to honey fungus(200)." PFAF-1

"White oak communities, Franklin and Dyrness reveal, come in several varieties, each named for the most prevalent understory shrub. These communities are called white oak/hazelnut, white oak/serviceberry, and gulp white oak/poison oak, which unfortunately is all too common around here. Each community contains a dozen or more associated plants...The tree also takes a decade or more to bear acorns..." [Hemenway GG]

Fire Regime: "Kalapuya and other local Native American groups were some of the first people to shape Willamette Valley ecosystems to meet their needs. Prior to European settlement they used fire as a management tool to maintain gardens of camas (Camassia quamash), a native prairie plant whose starchy bulb was a food staple, and to foster the growth of tarweed, grasshoppers, nut and berry plants, and bracken fern rhizomes (Agee 1993; Boyd 1999). They also set fires to herd deer for hunting. Oregon white oak (Quercus garryana) is adapted to fire in ways that other species are not. Its thick bark protects the delicate cambium, and dormant buds are located low on the root collar below the soil surface so they can sprout even after fire (Tveten and Fonda 1999). The fires the Kalapuya set thinned the understory of the oak woodlands and savannas, maintaining the stands’ open structure, enhancing tree vigor and seedling regeneration, and increasing mast crops for consumption by both humans and game (Agee 1993, 1996; Boyd 1999; Peter and Harrington 2002; Van Lear and Brose 2002). The fires also limited infestations by invasive plants and acorn-boring insects (Anderson 2005). The net effect of Kalapuyan management was to create an overstory of widely spaced, large-crowned Oregon white oak trees with an understory of shrubs and perennial native grasses (Agee 1990)." [Egan HDER]

''Burning was in the fall of the year when the plants were all dried up when it was going to rain. They’d burn areas when they would see it’s in need. If the brush was too high and too brushy it gets out of control. If the shrubs got two to four feet in height it would be time to burn. They’d burn every two years. Both men and women would set the fires. The flames wouldn’t get very high. It wouldn’t burn the trees, only the shrubs. They burned around the camping grounds where they lived and around where they gathered. They also cleared pathways between camps. Burning brush helped to save water. They burned in the valleys and foothills. I never heard of the Indians setting fires in the higher mountains, but don’t take my word for it. (Rosalie Bethel, North Fork Mono, pers. comm. 1991)'' [Anderson TTW]

Propagation

The seed "...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(11). Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly." PFAF-1


Quercus robur - English Oak

Identification
English Oak is an introduced European species in North America, where it is widely cultivated. It is reported from several US states ((MA, ME, NH, NY, OH, PA, RI), and five Canadian provinces (BC, NB, NS, ON, PE) (USDA 2010). While it is widely grown, it is naturalized only in Washington, New Brunswick and Nova Scotia (Flora North America Online 2010). In British Columbia, it is also naturalized,and is frequently encountered in the southwestern corner of the province, where it persists in areas where acorns have been introduced as squirrel food, or where it has been planted. It is often encountered as seedlings or young saplings under a forest canopy in drier sites near urban areas, particularly in areas of peat soil. Wild plants have been collected by Lomer in Squamish and on Sumas Mountain and it is frequent in drier parts of the Lulu Island Bog in Richmond. [E-flora]
Taxonomically, this is a tree species of oak in the white oak group (Quercus section Quercus). It most closely resembles the eastern North America white oak (Quercus alba). In British Columbia, it resembles Garry oak (Quercus garryana), but may be separated based on leaf lobing, leaf petiole length, and acorns. It reaches heights of 30 m and has shallowly lobed leaves with leaf stalks 1-3 mm in length. Fruits (acorns) occur on long stalks. [E-flora]

General: Deciduous spreading tree up to 30 m tall; bark light grey with thick scaly ridges. [IFBC-E-flora]

Similar Species
In British Columbia, English oak is most easily confused with the native Garry oak (Quercus garryanna). The two species may be separated by characteristics of leaf lobing, leaf stalks, and acorn morphology. In English oak, leaf lobing is shallow, less than halfway to the midrib, while in Garry oak lobing often extends more than halfway to the midrib. Leaf petioles in English oak are 1-3 mm long, while in Garry oak they are 1-2 cm long. English oak acorns have relatively long stalks, while Garry oak acorns are stalkless. Identification in oaks can be challenging because of the frequency of hybridization. [E-flora]

Hazards

Edible Uses

Other Uses

Medicinal Uses

The oak tree has a long history of medicinal use. It is anti-inflammatory, antiseptic, astringent, decongestant, haemostatic and tonic[4, 7, 9, 13, 21, 165]. The German Commission E Monographs, a therapeutic guide to herbal medicine, approve Quercus robur Pedunculate Oak for coughs/bronchitis, diarrhoea, inflammation of mouth and pharynx, inflammation of the skin (see [302] for critics of commission E).[PFAF]

Medicinal Parts: The medicinal parts are the dried bark of the young branches and the lateral shoots, the dried bark of the trunk and branches, the dried leaves of various oak species and the seed kernels without the seed coats. …Oak bark is harvested from March to April. The trees fall every 10 years. The bark is dried rapidly.

Compounds
Catechin tannins: oligomeric proanthocyanidins
Ellagitannins: (including castalagin, pedunculagin, vesvalagin, 2,3-(S)-hexahydroxy diphenoyl glucose), flavano-ellagitannins (acutissimins A and B, eugenigrandin, guajavacin B, stenophyllanin C) Gallo tannins Monomeric and dimeric catechins and leucocyanidins Tannins (12 to 16%)
Effects: The drug, which contains tannins, is astringent, antiphlogistic, antiviral and anthelmintic. [PDR]

Indications and Usage
Approved by Commission E: • Cough/bronchitis • Diarrhea • Inflammation of the mouth and pharynx • Inflammation of the skin [PDR]

Unproven Uses: Oak is used internally for non-specific diarrhea. In smaller doses it is used as a stomach tonic. The drug is used externally for inflammatory skin diseases, inflammation of the mouth and throat as well as the genital and anal area, suppurating eczema, hyperhydrosis, intertrigo and as an adjuvant treatment of chilblains. Oak is also used in folk medicine internally for hemorrhagic stool, non-menstrual uterine bleeding, hemoptysis and chronic inflammation of the gastrointestinal tract. External uses include hemorrhoid bleeding, varicose veins, uterine bleeding, vaginal discharge (washes/douches), rashes, chronic, itching, scaley and suppurating eczema and eye inflammations. [PDR]

Precautions & Adverse Effects

Cultivation
Mulch: A mulch of the leaves repels slugs, grubs etc, though fresh leaves should not be used as these can inhibit plant growth[20, 201].[PFAF]
Herbal Compost: The bark is an ingredient of 'Quick Return' herbal compost activator[32]. This is a dried and powdered mixture of several herbs that can be added to a compost heap in order to speed up bacterial activity and thus shorten the time needed to make the compost[K].[PFAF]

Prefers a good deep fertile loam which can be on the stiff side[11]. Young plants tolerate reasonable levels of side shade[200]. Succeeds in heavy clay soils[13] and in wet soils so long as the ground is not water-logged for long periods[186]. Dislikes dry or shallow soils but is otherwise drought tolerant once it is established[186]. Tolerant of exposed sites though it dislikes salt-laden winds[186]. The oak is a very important timber tree in Britain, it is also a very important food plant for the caterpillars of many species of butterfly[30], there are 284 insect species associated with this tree[24]. It has often been coppiced or pollarded for its wood in the past[23], though this should not be done too frequently[186], about once every 50 years is the average. The tree flowers on new growth produced in spring, the seed ripening in its first year[200, 229]. Older trees have a thick corky bark and this can protect them from forest fires, young trees will often regenerate from the base if cut down or killed back by a fire[186]. Intolerant of root disturbance, trees should be planted in their permanent positions whilst young[11]. Hybridizes freely with other members of the genus[200]. Immune to attacks by the tortix moth[1]. This species is notably resistant to honey fungus[88, 200].[PFAF]

Propagation
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[11]. Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly.[PFAF]

Uses of Related Sp.

"All acorns are good to eat. Some are less sweet than others, that's all. But the bitterness that is prevalent in different degrees is due to tannin....The oaks may be separated into two great groups: the white oaks and the red oaks. The acorns of the former are the sweet ones....Indians leached their bitter acorns in a number of ways. Sometimes the acorns would be buried in swamp mud for a year, after which they would be ready for roasting and eating whole. Other tribes let their shelled acorns mold in baskets, then buried them in clean freshwater sand. When they had turned black, they were sweet and ready for use. " Angier FFWE "Many of the sweet acorns borne by the White Oak group are not at all unpleasant eaten raw. Gibbons SHH "Only the scrub Oaks were not generally used by the Indians, though even these were taken in times of acute shortage of other food." EUCP

Quercus Sp.
It has been said that the Oaks produce more nuts annually than all other wild and cultivated nut trees combined. Tozer UWP

References


Page last modified on Friday, April 13, 2018 12:16 PM