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Quercus ilex ballota - (Desf.)A.DC.

Holm Oak

Author	(Desf.)A.DC.	Botanical references	11, 89, 200
Family	Fagaceae	Genus	Quercus
Synonyms	Quercus ballota - Desf. Quercus rotundifolia - Lam.
Known Hazards	None known
Range	Europe - Mediterranean.
Habitat	Arid places, maquis, woods and hills on limestone[89].
Edibility Rating	5 (1-5)	Medicinal Rating	2 (1-5)

Physical Characteristics

An evergreen Tree growing to 25m by 20m at a slow rate.

The plant prefers light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay soil. The plant prefers acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It requires moist soil. The plant can tolerate maritime exposure.

Habitats

Woodland Garden; Canopy; Hedge;

Edible Uses

Edible Parts: Seed.

Edible Uses: Coffee; Oil.

Seed - raw or cooked[1, 2, 46, 63, 200]. The seed of this variety is normally sweet. The seed is up to 3cm long[200], it can be dried, ground into a powder and used as a thickening in stews etc or mixed with cereals for making bread. The seed from some trees contains bitter tannins, these can be leached out by thoroughly washing the seed in running 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. An edible oil is obtained from the seed[183].

Medicinal Uses

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

Astringent.

Any galls produced on the tree are strongly astringent and can be used in the treatment of haemorrhages, chronic diarrhoea, dysentery etc[4].

Other Uses

Fuel; Hedge; Repellent; Shelterbelt; Tannin; Wood.

A mulch of the leaves repels slugs, grubs etc, though fresh leaves should not be used as these can inhibit plant growth[20]. 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[4]. Very tolerant of maritime exposure and of trimming, it can be grown as a shelterbelt tree or hedge in maritime areas[11, 29, 49, 75]. Wood - strong, hard, durable. Used for furniture[46, 61, 89]. It makes a good charcoal[89] and a good fuel, burning well even if green[146]. The bark is a source of tannin[146].

Cultivation details

Prefers a good deep fertile loam which can be on the stiff side[11]. Thrives on shallow chalky soils[188]. Succeeds in all soils except those that are cold and poorly drained[98]. Grows well in sandy soils[188]. Young plants tolerate reasonable levels of side shade[200]. Very resistant to maritime exposure[11, 49, 75]. A very ornamental[1] though quite slow-growing tree[75]. Transplants badly unless moved regularly and this should be done as growth commences in late May or in September[11]. This plant is treated as a distinct species, Q. rotundifolia. Lam. by some botanists[50]. Cultivated for its edible seed in Spain[11, 63]. The tree grows well in Britain but is said to fruit poorly here[11], however a tree at Kew was bearing a very good crop at the end of the hot summer of 1989 and again in 1991[K]. The seed ripens in its first year[200]. Hybridizes freely with other members of the genus[200]. This species is notably resistant to honey fungus[88, 200].

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.

Links

This plant is also mentioned in the following PFAF articles: Staple seed crops from perennials..

References

[K] Ken Fern
Notes from observations, tasting etc at Plants For A Future and on field trips.

[1] F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaces in 1992 by a new dictionary (see [200]).

[2] Hedrick. U. P. Sturtevant's Edible Plants of the World. Dover Publications 1972 ISBN 0-486-20459-6
Lots of entries, quite a lot of information in most entries and references.

[4] Grieve. A Modern Herbal. Penguin 1984 ISBN 0-14-046-440-9
Not so modern (1930's?) but lots of information, mainly temperate plants.

[11] Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981
A classic with a wealth of information on the plants, but poor on pictures.

[20] Riotte. L. Companion Planting for Successful Gardening. Garden Way, Vermont, USA. 1978 ISBN 0-88266-064-0
Fairly good.

[29] Shepherd. F.W. Hedges and Screens. Royal Horticultural Society. 1974 ISBN 0900629649
A small but informative booklet giving details of all the hedging plants being grown in the R.H.S. gardens at Wisley in Surrey.

[46] Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim 1959
An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.

[49] Arnold-Forster. Shrubs for the Milder Counties. 0
Trees and shrubs that grow well in Cornwall and other mild areas of Britain. Fairly good, a standard reference book.

[50] ? Flora Europaea Cambridge University Press 1964
An immense work in 6 volumes (including the index). The standard reference flora for europe, it is very terse though and with very little extra information. Not for the casual reader.

[61] Usher. G. A Dictionary of Plants Used by Man. Constable 1974 ISBN 0094579202
Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.

[63] Howes. F. N. Nuts. Faber 1948
Rather old but still a masterpiece. Has sections on tropical and temperate plants with edible nuts plus a section on nut plants in Britain. Very readable.

[75] Rosewarne experimental horticultural station. Shelter Trees and Hedges. Ministry of Agriculture, Fisheries and Food 1984
A small booklet packed with information on trees and shrubs for hedging and shelterbelts in exposed maritime areas.

[88] RHS. The Garden. Volume 112. Royal Horticultural Society 1987
Snippets of information from the magazine of the RHS. In particular, there are articles on plants that are resistant to honey fungus, oriental vegetables, Cimicifuga spp, Passiflora species and Cucurbits.

[89] Polunin. O. and Huxley. A. Flowers of the Mediterranean. Hogarth Press 1987 ISBN 0-7012-0784-1
A very readable pocket flora that is well illustrated. Gives some information on plant uses.

[98] Gordon. A. G. and Rowe. D. C. f. Seed Manual for Ornamental Trees and Shrubs. 0
Very comprehensive guide to growing trees and shrubs from seed. Not for the casual reader.

[146] Gamble. J. S. A Manual of Indian Timbers. Bishen Singh Mahendra Pal Singh 1972
Written last century, but still a classic, giving a lot of information on the uses and habitats of Indian trees. Not for the casual reader.

[183] Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990 ISBN 0-9628087-0-9
Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.

[188] Brickell. C. The RHS Gardener's Encyclopedia of Plants and Flowers Dorling Kindersley Publishers Ltd. 1990 ISBN 0-86318-386-7
Excellent range of photographs, some cultivation details but very little information on plant uses.

[200] Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992 ISBN 0-333-47494-5
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.

Readers Comments

Plants for a Future does not verify the accuracy of reader comments, use at your own risk. In particular Plants For A Future can not take any responsibility for any adverse effects from the use of plants. You should always consult a professional before using plants medicinally.

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