Quercus macrocarpa
Burr Oak
a perennial woody deciduous member of the Quercus genus in the family Fagaceae.
Taxonomy and growth
Uses
Edible uses
This section contains historical Plants For A Future notes marked noncommercial.
Seed - cooked[1][2][6][15]. Very large, the seed can be up to 5cm x 4cm[21][11], though it is somewhat variable in size and shape[13]. The seed can be ground into a powder and used in making bread, dumplings etc and as a thickener in soups[8]. The seed of this species is considered to be one of the most palatable of all the oaks[5][8]. Many trees have sweet seeds with little tannin and the seed can be eaten raw or cooked. If the seed is bitter then this is due to the presence of tannins, these can be leached out by thoroughly washing the dried and ground up seed in water, though many minerals will also be lost. 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.
- Plant part
- Seed
Medicinal uses
Historical medicinal uses. These records describe reported uses. They do not establish safety or effectiveness. Ask a qualified health professional before using any plant medicinally.
This section contains historical Plants For A Future notes marked noncommercial.
The bark is astringent and tonic[20]. An infusion has been used in the treatment of diarrhoea[15]. A decoction of the root or inner bark has been used in the treatment of cramps[15]. Any galls produced on the tree are strongly astringent and can be used in the treatment of haemorrhages, chronic diarrhoea, dysentery etc[17].
- Product or use
- Antispasmodic
- Product or use
- Astringent
- Product or use
- Tonic
Material uses
This section contains historical Plants For A Future notes marked noncommercial.
A mulch of the leaves repels slugs, grubs etc, though fresh leaves should not be used as these can inhibit plant growth[10]. 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[17]. The bark has been used as a mordant for fixing dyes[15]. Wood - hard, heavy, strong, tough, very durable, close grained. It weighs about 46lb per cubic metre[13]. Of considerable importance as a timber tree, it is used for all types of construction, in making baskets, flooring, cabinet making, ship building etc[19][20][21][4][7][13][14]. It is also a good fuel[21].
- Product or use
- Mordant
- Product or use
- Repellent
- Product or use
- Tannin
- Product or use
- Wood
Ecology and functions
- Ecosystem niche
- Canopy
Environment
- Range
- Eastern N. America - Nova Scotia to Manitoba, Wyoming, Massachusetts, Georgia, Kansas and Texas.
- Habitat
- Found in a variety of habitats from dry hillsides to moist bottomlands, rich woods and fertile slopes, mainly on limestone soils[18][14].
- Light
- full sun
- Shade tolerance
- light shade
- Water
- moderate
- Hardiness
- Zone 3+
- Soil textures
- loamy, clay, heavy clay
- Soil pH
- acid, neutral, alkaline
- Tolerances
- high wind, drought
- Wind
- Yes
- Tolerates Nutritionally Poor Soil
- No
- Drought
- tolerant
Propagation
This section contains historical Plants For A Future notes marked noncommercial.
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[3]. Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly.
Cultivation
This section contains historical Plants For A Future notes marked noncommercial.
Prefers a good deep fertile loam which can be on the stiff side[3]. Lime tolerant[9]. Succeeds in a hot dry position. Young plants tolerate reasonable levels of side shade[11]. Tolerates moderate exposure, surviving well but being somewhat stunted[11]. A slow-growing tree[9]. Established plants are drought resistant[14] and tolerant of atmospheric pollution[12]. Trees have a thick, fire-resistant bark[16]. Occasionally cultivated for its edible seed, there are some named varieties[8]. Slow growing in the wild, it takes about 30 years to start producing seed, though it then continues to crop for the next 200 - 300 years with large crops being produced every 2 - 3 years[14]. The tree flowers on new growth produced in spring, the seed ripening in its first year[11][14]. Prefers warmer summers than are usually experienced in Britain, often growing poorly in this country and failing to properly ripen its wood, resulting in frost damage overwinter[3][11]. A tree at the Hillier Arboretum in Hampshire was growing well in September 1993. It was 9 metres tall but had a lot of mildew, there was no sign of seeds[K]. There is a dwarf form of this species:- Q. macrocarpa depressa (Nutt.)Engelm. grows about 2 metres tall with corky branches and smaller seeds than the species, usually about 1cm long[13]. Hybridizes freely with other members of the genus[11]. Plants in this genus are notably resistant to honey fungus[11].
References
Turner. N. J. and Szczawinski. A. Edible Wild Fruits and Nuts of Canada. National Museum of Natural Sciences 1978-00-00
Tanaka. T. Tanaka's Cyclopaedia of Edible Plants of the World. Keigaku Publishing 1976-00-00
Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981-00-00
Vines. R. A. Trees of Central Texas. University of Texas Press 1987-00-00 ISBN 0-292-78958-3
McPherson. A. and S. Wild Food Plants of Indiana. Indiana University Press 1977-00-00 ISBN 0-253-28925-4
Yanovsky. E. Food Plants of the N. American Indians. Publication no. 237. U.S. Depf of Agriculture.
Hill. A. F. Economic Botany. The Maple Press 1952-00-00
Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990-00-00 ISBN 0-9628087-0-9
Brickell. C. The RHS Gardener's Encyclopedia of Plants and Flowers Dorling Kindersley Publishers Ltd. 1990-00-00 ISBN 0-86318-386-7
Riotte. L. Companion Planting for Successful Gardening. Garden Way, Vermont, USA. 1978-00-00 ISBN 0-88266-064-0
Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5
Lauriault. J. Identification Guide to the Trees of Canada Fitzhenry and Whiteside, Ontario. 1989-00-00 ISBN 0889025649
Vines. R.A. Trees of North Texas University of Texas Press. 1982-00-00 ISBN 0292780206
Elias. T. The Complete Trees of N. America. Field Guide and Natural History. Van Nostrand Reinhold Co. 1980-00-00 ISBN 0442238622
Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998-00-00 ISBN 0-88192-453-9
Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J Illustrated Flora of North Central Texas Botanical Research Institute, Texas. 1999-00-00 http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm
Grieve. A Modern Herbal. Penguin 1984-00-00 ISBN 0-14-046-440-9
Fernald. M. L. Gray's Manual of Botany. American Book Co. 1950-00-00
Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim 1959-00-00
Usher. G. A Dictionary of Plants Used by Man. Constable 1974-00-00 ISBN 0094579202
Sargent. C. S. Manual of the Trees of N. America. Dover Publications Inc. New York. 1965-00-00 ISBN 0-486-20278-X