Juglans Regia , Common Walnut, Black Walnut

 

Medicinal Uses

Alterative; Anodyne; Antiinflammatory; Astringent; Bach; Blood purifier; Cancer; Depurative; Detergent; Diuretic; Laxative; Lithontriptic; Pectoral; Skin; Stimulant; Vermifuge.

Dictionary:

  1. Alterative = Tending to restore to normal health
  2. Anodyne = Capable of soothing or eliminating pain
  3. Antiinflammatory = Preventing or reducing inflammation.
  4. Astringent = Tending to draw together or constrict tissues; styptic.
  5. Blood purifier = agent that rids blood of impurities; cleanse.
  6. Blood  tonic = invigorating, refreshing and restoring blood
  7. Depurative = Purifying the blood
  8. Detergent = A cleansing substance that acts similarly to soap
  9. Diuretic = Tending to increase the discharge of urine.
  10. Laxative = stimulates evacuation of the bowels
  11. Lithontriptic= Used for, dissolving or destroying stone in the bladder or kidneys
  12. Pectoral = Useful in relieving disorders of the chest or respiratory tract.
  13. Vermifuge = Anthelmintic = expelling or destroying parasitic worms especially of the intestine

 

The cotyledons are used in the treatment of cancer[218]. Walnut has a long history of folk use in the treatment of cancer, some extracts from the plant have shown anticancer activity[218].

The seeds are antilithic, diuretic and stimulant[218]. They are used internally in the treatment of low back pain, frequent urination, weakness of both legs, chronic cough, asthma, constipation due to dryness or anaemia and stones in the urinary tract[176]. Externally, they are made into a paste and applied as a poultice to areas of dermatitis and eczema[176].

The leaves are alterative, anthelmintic, antiinflamatory, astringent and depurative[9, 218]. They are used internally the treatment of constipation, chronic coughs, asthma, diarrhoea, dyspepsia etc[9]. The leaves are also used to treat skin ailments and purify the blood[9, 218]. They are considered to be specific in the treatment of strumous sores[240].

Male inflorescences are made into a broth and used in the treatment of coughs and vertigo[218].

The rind is anodyne and astringent[147]. It is used in the treatment of diarrhoea and anaemia[238].


The oil from the seed is anthelmintic[218]. It is also used in the treatment of menstrual problems and dry skin conditions[238].


The bark and rootbark are anthelmintic, astringent and detergent[218, 240].

The plant is used in Bach flower remedies - the keywords for prescribing it are 'Oversensitive to ideas and influences' and 'The link-breaker'[209].

 

Common name: Walnut Family: Juglandaceae
Known Hazards: None known
Range: E. Europe to N. Asia. More or less naturalized in S. Britain.
Habitat: Forests in the Himalayas, preferring a northerly aspect in the west but a southerly or westerly aspect in the east of the range[144].

Other Posible Synonyms: From various places across the web, may not be correct. See below.
J. duclouxiana[G] J. fallax[G] J. kamaonica[G] J. nigra[H] J. orientis[G] J. regia subsp. kamaonica[G] J. regia var. orientis[G] J. regia var. sinensis[G] J. sinensis[G]
Other Common Names: From various places around the Web, may not be correct. See below.
Black Walnut [H], Ceviz Agaci [E], Ch'Iang T'Ao [E], Common Walnut [H], English Walnut [H,P,B], Guz [E], Hei T'Ao [E], Hu T'Ao [E], Hu Tao [E], Jawiz [E], Joz [E], Nogal [E], Persian Walnut [H], Qoz [E], Walnut [H],
Epithets: From a Dictionary of Botanical Epithets
regia = royal;
Other Range Info: From the Ethnobotany Database
China; India; Iraq; Mexico; Nepal; Spain; Turkey

Physical Characteristics

A decidious tree growing to 20m by 20m at a medium rate. It is hardy to zone 5 and is frost tender. It is in flower in June, and the seeds ripen in October. The scented 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. The plant is self-fertile. We rate it 4 out of 5 for usefulness.

The plant prefers light (sandy), medium (loamy) and heavy (clay) soils and requires well-drained soil. The plant prefers acid, neutral and basic (alkaline) soils. It cannot grow in the shade. It requires moist soil.

 

Edible Uses

Oil; Sap; Seed; Sweetener; Tea.

Seed - eaten raw or used in confections, cakes, ice cream etc[2, 5, 12, 34, 183]. A delicious flavour. The seed can also be ground into a meal and used as a flavouring in sweet and savoury dishes[183]. The unripe fruits are pickled in vinegar[183].

An edible oil is obtained from the seed[4, 7, 57, 183], it should not be stored for any length of time since it tends to go rancid quickly[7, 132]. The oil has a pleasant flavour and is used in salads or for cooking[183].

The sap is tapped in spring and used to make a sugar[117].

The finely ground shells are used in the stuffing of 'agnolotti' pasta[183].

The leaves are used as a tea[183].

Other Uses

Dye; Herbicide; Oil; Paint; Polish; Repellent; Tannin; Teeth; Wood.

A yellow dye is obtained from the green husks[4, 7, 100, 117]. It is green[148]. The green nuts (is this the same as the green husks?) and the leaves are also used[148]. The rind of unripe fruits is a good source of tannin[158].

A brown dye is obtained from the leaves and mature husks[4, 7, 48, 117, 168]. It does not require a mordant and turns black if prepared in an iron pot[168]. The dye is often used as a colouring and tonic for dark hair[238]. The leaves and the husks can be dried for later use[169].

A golden-brown dye is obtained from the catkins in early summer. It does not require a mordant[168].

A drying oil is obtained from the seed. It is used in soapmaking, paints, etc. It is not very stabe and quickly goes rancid[7, 21, 34, 46].

The nuts can be used as a wood polish. Simply crack open the shell and rub the kernel into the wood to release the oils. Wipe off with a clean cloth[4, 6, K].

The dried fruit rind is used to paint doors, window frames etc[145] (it probably protects the wood due to its tannin content).

The leaves contain juglone, this has been shown to have pestcidal and herbicidal properties[218]. The crushed leaves are an insect repellent[46, 61].

Juglone is also secreted from the roots of the tree, it has an inhibitory effect on the growth of many other plants[201].

Bark of the tree and the fruit rind are dried and used as a tooth cleaner. They can also be used fresh[145, 158].

Wood - heavy, hard, durable, close grained, seasons and polishes well. A very valuable timber tree, it is used for furniture making, veneer etc[1, 4, 7, 46, 61, 158].

Cultivation details

Requires a deep well-drained loam[11] and a sunny position sheltered from strong winds. Prefers a slightly alkaline heavy loam but succeeds in most soils[1, 63].

The dormant plant is very cold tolerant, but the young growth in spring can be damaged by late frosts. Some late-leafing cultivars have been developed, these often avoid damage from spring frosts and can produce a better quality timber tree.

The walnut tree is frequently cultivated for its edible seed in temperate zones of the world, there are many named varieties[63, 183]. Trees grow well in most areas of Britain but they often fail to fully ripen their fruits or their wood in our cooler and damper climate[63, 200], they prefer a more continental climate. There are some very fine trees in Cornwall[59]. Walnuts can produce large healthy trees in many parts of Britain, but seedling trees often do not fruit reliably. Some European varieties have been developed that succeed in colder areas[200]. Seedling trees are said to take from 6 to 15 years to come into fruit from seed[200], but these cultivars usually start cropping within 5 years.

Plants produce a deep taproot and they are intolerant of root disturbance. Seedlings should be planted out into their permanent positions as soon as possible and given some protection for their first winter or two since they are somewhat tender when young.

Flower initiation depends upon suitable conditions in the previous summer. The flowers and young growths can be destroyed by even short periods down to -2°c[63], but fortunately plants are usually late coming into leaf. Some cultivars are self-fertile, though it is generally best to grow at least two different cultivars to assist in cross-pollination.

Any pruning should only be carried out in late summer to early autumn or when the plant is fully dormant otherwise wounds will bleed profusely and this will severely weaken the tree.

Plants produce chemicals which can inhibit the growth of other plants. These chemicals are dissolved out of the leaves when it rains and are washed down to the ground below, reducing the growth of plants under the tree[18, 20, 159]. The roots also produce substances that are toxic to many plant species, especially apples (Malus species), members of the Ericaceae, Potentilla spp and the white pines (certain Pinus spp.)[200]. Trees have a dense canopy which tends to reduce plant growth below them[20]. All in all, not the best of companion trees, it is also suggested that the trees do not like growing together in clumps[37]. Trees are said to inhibit the growth of potatoes and tomatoes[18].

Hybridizes with J. nigra[149].

This species is notably susceptible to honey fungus[200].

The bruised leaves have a pleasant sweet though resinous smell[245].

Propagation

The seed is best sown as soon as it is ripe in individual deep pots in a cold frame[80]. You need to protect it from mice, birds, squirrels etc. The seed usually germinates in late winter or the spring. Plant out the seedlings into their permanent positions in early summer and give some protection from the cold for their first winter or two.

The seed can also be stored in cool moist conditions (such s the salad compartment of a fridge) over the winter and sown in early spring but it may then require a period of cold stratification before it will germinate[78, 80, 113].

Named varieties are propagated by budding.

Scent

Leaves: Crushed
The bruised leaves have a pleasant sweet though resinous smell.

Cultivars

'Rita'
A small growing tree, it flowers earlier than most other varieties. Cropping prolifically, it is very hardy and self-fertile.
'Proslavski'
Stronger growing than 'Plovdivski', it produces large nuts of excellent flavour. At least partially self-sterile, the cultivar 'Buccaneer' is a good pollinator.
'Plovdivski'
The tree forms a broad crown and produces large nuts of excellent flavour. At least partially self-sterile, the cultivars 'Buccaneer', 'Coenen' and 'Rita' are good pollinators.
'Number 16'
Very similar to 'Rita, but rather more vigorous, it flowers earlier than most other varieties. Cropping prolifically, it is very hardy and self-fertile.
'Franquette'
A medium to large nut with a well-sealed thin shell, it has a very good flavour[183]. A large tree, it is partially self-fertile but has relatively low yields and lacks lateral-bud fruitfulness[183]. The cultivar 'Buccaneer' is a good pollinator. Very late coming into leaf, it is not susceptible to spirng frost damage[183]. It is slow to come into bearing, but is long-lived[183]. This cultivar is not as well suited to the British climate as some of the newer cultivars.
'Coenen'
A prolific cropper with large nuts. At least partially self-sterile, the cultivar 'Buccaneer' is a good pollinator. A strong growing tree.
'Buccaneer'
Produces an abundant crop of seeds. A self-fertile cultivar, it produces pollen over a long period and is thus a valuable pollinator for other cultivars. The tree is about the same size as a seedling walnut, it comes into leaf very late and so usually avoids damage by late frosts.
'Broadview'
A medium to large nut with a soft, well-sealed shell of good cracking quality[183]. It ripens slightly earlier than the cultivar 'Franquette', beginning in September, and keeps well[183]. The tree is late coming into leaf and very hardy. It is probably also apomictic, forming nuts without pollination. A very productive, lateral-bearing tree, it is very hardy[183]. The tree is somewhat smaller than seed-grown walnuts.

PFAF Web Pages

This plant is mentioned in the following web pages

Web References

See the PFAF Links Pages for other sources or the The Gatherer where you can search many other sources all in one go.

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.

[5] Mabey. R. Food for Free. Collins 1974 ISBN 0-00-219060-5
Edible wild plants found in Britain. Fairly comprehensive, very few pictures and rather optimistic on the desirability of some of the plants.

[6] Mabey. R. Plants with a Purpose. Fontana 1979 ISBN 0-00-635555-2
Details on some of the useful wild plants of Britain. Poor on pictures but otherwise very good.

[7] Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald 1984 ISBN 0-356-10541-5
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.

[9] Launert. E. Edible and Medicinal Plants. Hamlyn 1981 ISBN 0-600-37216-2
Covers plants in Europe. a drawing of each plant, quite a bit of interesting information.

[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.

[12] Loewenfeld. C. and Back. P. Britain's Wild Larder. David and Charles ISBN 0-7153-7971-2
A handy pocket guide.

[18] Philbrick H. and Gregg R. B. Companion Plants. Watkins 1979
Details of beneficial and antagonistic relationships between neighbouring plants.

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

[21] Lust. J. The Herb Book. Bantam books 1983 ISBN 0-553-23827-2
Lots of information tightly crammed into a fairly small book.

[34] Harrison. S. Wallis. M. Masefield. G. The Oxford Book of Food Plants. Oxford University Press 1975
Good drawings of some of the more common food plants from around the world. Not much information though.

[37] Thompson. B. The Gardener's Assistant. Blackie and Son. 1878
Excellent general but extensive guide to gardening practices in the 19th century. A very good section on fruits and vegetables with many little known species.

[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.

[48] Boullemier. L. The Checklist of Species, Hybrids and Cultivars of the Genus Fuschia. Blandford Press 1985 ISBN 0-7137-1781-5
Merely a list of names and the occasional elaboration.

[57] Schery. R. W. Plants for Man.
Fairly readable but not very comprehensive. Deals with plants from around the world.

[59] Thurston. Trees and Shrubs in Cornwall.
Trees and shrubs that succeed in Cornwall based on the authors own observations. Good but rather dated.

[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.

[78] Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948
A bit dated but a good book on propagation techniques with specific details for a wide range of plants.

[80] McMillan-Browse. P. Hardy Woody Plants from Seed. Grower Books 1985 ISBN 0-901361-21-6
Does not deal with many species but it is very comprehensive on those that it does cover. Not for casual reading.

[100] Polunin. O. Flowers of Europe - A Field Guide. Oxford University Press 1969 ISBN 0192176218
An excellent and well illustrated pocket guide for those with very large pockets. Also gives some details on plant uses.

[113] Dirr. M. A. and Heuser. M. W. The Reference Manual of Woody Plant Propagation. Athens Ga. Varsity Press 1987 ISBN 0942375009
A very detailed book on propagating trees. Not for the casual reader.

[117] Rosengarten. jnr. F. The Book of Edible Nuts. Walker & Co. 1984 ISBN 0802707699
A very readable and comprehensive guide. Well illustrated.

[132] Bianchini. F., Corbetta. F. and Pistoia. M. Fruits of the Earth.
Lovely pictures, a very readable book.

[144] Cribb. A. B. and J. W. Wild Food in Australia. Fontana 1976 ISBN 0-00-634436-4
A very good pocket guide.

[145] Singh. Dr. G. and Kachroo. Prof. Dr. P. Forest Flora of Srinagar. Bishen Singh Mahendra Pal Singh 1976
A good flora of the western Himalayas but poorly illustrated. Some information on plant uses.

[147] ? A Barefoot Doctors Manual. Running Press ISBN 0-914294-92-X
A very readable herbal from China, combining some modern methods with traditional chinese methods.

[148] Niebuhr. A. D. Herbs of Greece. Herb Society of America. 1970
A pleasant little book about Greek herbs.

[149] Vines. R. A. Trees of Central Texas. University of Texas Press 1987 ISBN 0-292-78958-3
Fairly readable, it gives details of habitats and some of the uses of trees growing in Texas.

[158] Gupta. B. L. Forest Flora of Chakrata, Dehra Dun and Saharanpur. Forest Research Institute Press 1945
A good flora for the middle Himalayan forests, sparsly illustrated. Not really for the casual reader.

[159] McPherson. A. and S. Wild Food Plants of Indiana. Indiana University Press 1977 ISBN 0-253-28925-4
A nice pocket guide to this region of America.

[168] Grae. I. Nature's Colors - Dyes from Plants. MacMillan Publishing Co. New York. 1974 ISBN 0-02-544950-8
A very good and readable book on dyeing.

[169] Buchanan. R. A Weavers Garden.
Covers all aspects of growing your own clothes, from fibre plants to dyes.

[176] Yeung. Him-Che. Handbook of Chinese Herbs and Formulas. Institute of Chinese Medicine, Los Angeles 1985
A very good Chinese herbal.

[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.

[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.

[201] Allardice.P. A - Z of Companion Planting. Cassell Publishers Ltd. 1993 ISBN 0-304-34324-2
A well produced and very readable book.

[209] Chancellor. P. M. Handbook of the Bach Flower Remedies C. W. Daniel Co. Ltd. 1985 ISBN 85207 002 0
Details the 38 remedies plus how and where to prescribe them.

[218] Duke. J. A. and Ayensu. E. S. Medicinal Plants of China Reference Publications, Inc. 1985 ISBN 0-917256-20-4
Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.

[238] Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. 1995 ISBN 0-7513-020-31
A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.

[240] Chopra. R. N., Nayar. S. L. and Chopra. I. C. Glossary of Indian Medicinal Plants (Including the Supplement). Council of Scientific and Industrial Research, New Delhi. 1986
Very terse details of medicinal uses of plants with a wide range of references and details of research into the plants chemistry. Not for the casual reader.

[245] Genders. R. Scented Flora of the World. Robert Hale. London. 1994 ISBN 0-7090-5440-8
An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.