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Fabaceae FAMILY

Gymnocladus dioicus

Gymnocladus dioicus

Edibility
2/5
Medicinal
2/5

Safety & Hazards

The ripe seed contains hydrocyanic acid. This toxin can be destroyed by thoroughly heating the seed for at least 3 hours at 150°c[1]. The seed contains saponins[2]. Although poisonous, saponins also have a range of medicinal applications and many saponin-rich plants are used in herbalism (particularly as emetics, expectorants and febrifuges) or as sources of raw materials for the pharmaceutical industry. Saponins are also found in a number of common foods, such as many beans. Saponins have a quite bitter flavour and are in general poorly absorbed by the human body, so most pass through without harm. They can be removed by carefully leaching in running water. Thorough cooking, and perhaps changing the cooking water once, will also normally remove most of them. However, it is not advisable to eat large quantities of raw foods that contain saponins. Saponins are much more toxic to many cold-blooded creatures, such as fish, and hunting tribes have traditionally put large quantities of them in streams, lakes etc in order to stupefy or kill the fish and make them easy to catch[PFAF].

Cultivation Details

HabitDeciduous Tree
GrowthMedium

Gymnocladus dioicus is a very cold-hardy plant, tolerating temperatures down to about -30°c when fully dormant[3]. It requires a climate with a hot summer, however, if it is to flower amd set fruit - flowers are seldom formed in areas with cooler summers[4]. Requires a sunny position[3]. Grows best in a deep rich soil[5, 3]. Tolerant of a wide range of soils, including poor soils, but dislikes heavy clays[6, 7]. Tolerates atmospheric pollution, saline soils and limestone soils[3]. Established plants are drought tolerant, and can also withstand occasional inundation of the soil[8, 6]. A very ornamental plant, it is the state tree of Kentucky[5, 7]. Often very slow growing in cultivation[4, 3], plants in the wild are somewhat faster and can reach a height of 3.5 - 4 metres in 10 years from seed[8]. Trees in the wild seldom live longer than 100 years[9]. A dioecious species - both male and female forms must be grown if fruit and seed are required. Unlike most members of the Leguminosae, his species does not form nodules of nitrogen-producing bacteria on the roots[10].

Propagation

Seed - best sown in a greenhouse as soon as it is ripe[3]. The seed can also be sown in early spring in a greenhouse[11]. Scarification and pre-soaking the seed for 24 hours in warm water, especially if it has been stored, will improve germination[3]. Make sure the seed has swollen after soaking, soak it again if it has not and, if it still does not swell, try filing away some of the seedcoat but be careful not to damage the embryo. As soon as they are large enough to handle, prick the seedlings out into fairly deep individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Consider giving them some protection against the cold for their first couple of winters outdoors Root cuttings 4cm long and 1cm thick in a greenhouse in December[3]. Plant the roots horizontally in pots[11]. Good percentage. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Gymnocladus+dioicus>

Pollinators

Data unavailable

References

  1. [1]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · 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.
  2. [2]A Field Guide to Medicinal Plants. Eastern and Central N. America. — Foster. S. & Duke. J. A. · Houghton Mifflin Co. · 1990 · ISBN 0395467225 ↩︎A concise book dealing with almost 500 species. A line drawing of each plant is included plus colour photographs of about 100 species. Very good as a field guide, it only gives brief details about the plants medicinal properties.
  3. [3]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · 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.
  4. [4]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
  5. [5]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
  6. [6]KemperCentreForHomeGardeningPlantFinder — Missouri Botanical Garden · http://www.mobot.org/gardeninghelp/plantfinder/ ↩︎Basic cultivation details, plant uses, habitat etc for several thousand species of plants, mainly from the temperate zone.
  7. [7]Southern Trees Fact Sheets — Gilman E.F. · University of Florida, IFAS Extension · http://edis.ifas.ufl.edu/department_envhort-trees ↩︎A series of fact sheets on trees that can be grown in Florida. They can be downloaded from the Internet
  8. [8]Plants Database — United States Department of Agriculture · http://plants.usda.gov/java/factSheet ↩︎An online database with an excellent collection of fact sheets about native N. American plants.
  9. [9]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.
  10. [10]Illustrated Flora of North Central Texas — Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J · Botanical Research Institute, Texas. · 1999 · http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm · ISBN 1-889878-01-4 ↩︎An excellent flora, which is also available on-line.
  11. [11]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
  12. [12]The anomalous Kentucky coVeetree: megafaunal fruit sinking to extinction? — Zaya D.N.; Howe H.F. · 2009 · http://doi.org/10.1007/s00442-009-1372-3 ↩︎
  13. [13]Sturtevant's Edible Plants of the World. — Hedrick. U. P. · Dover Publications · 1972 · ISBN 0-486-20459-6 ↩︎Lots of entries, quite a lot of information in most entries and references.
  14. [14]Manual of the Trees of N. America. — Sargent. C. S. · Dover Publications Inc. New York. · 1965 · http://www.biodiversitylibrary.org/ · ISBN 0-486-20278-X ↩︎Two volumes, a comprehensive listing of N. American trees though a bit out of date now. Good details on habitats, some details on plant uses. Not really for the casual reader. It can be downloaded from the internet.
  15. [15]Poisonous Plants of North Carolina — http://www.ces.ncsu.edu/depts/hort/consumer/poison/poison.htm ↩︎An excellent concise but comprehensive guide to toxic plants that grow in N. Carolina. It lists even those plants that are of very low toxicity, including several well-known food plants such as carrots and potatoes.
  16. [16]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎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.
  17. [17]Edible and Useful Wild Plants of the United States and Canada. — Saunders. C. F. · Dover Publications · 1976 · ISBN 0-486-23310-3 ↩︎Useful wild plants of America. A pocket guide.
  18. [18]Earth Medicine, Earth Food. — Weiner. M. A. · Ballantine Books · 1980 · ISBN 0-449-90589-6 ↩︎A nice book to read though it is difficult to look up individual plants since the book is divided into separate sections dealing with the different medicinal uses plus a section on edible plants. Common names are used instead of botanical.
  19. [19]Identification Guide to the Trees of Canada — Lauriault. J. · Fitzhenry and Whiteside, Ontario. · 1989 · ISBN 0889025649 ↩︎Very good on identification for non-experts, the book also has a lot of information on plant uses.
  20. [20]Food Plants of the N. American Indians. — Yanovsky. E. · U.S. Depf of Agriculture. · ISBN - ↩︎A comprehensive but very terse guide. Not for the casual reader.
  21. [21]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
  22. [22]Plants of Possible Insecticidal Value - A Review of the Literature up to 1941 — McIndoo N.E. · USDA; Bureau of Entomology and Plant Quarantine · 1945 ↩︎Information on the insecticidal properties (or not) of almost 1,200 species of plant. Rather dated but still with information hard to obtain elsewhere. It can be downloaded from the Intenet
  23. [23]Botanical Beads — Smith R.J. · http://www.botanicalbeads.com/ ↩︎A website looking at seeds that are used for ornament. It is based on a book that the author had written.
  24. [24]A Dictionary of Plants Used by Man. — Usher. G. · 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.
  25. [25]Economic Botany. — Hill. A. F. · The Maple Press · 1952 · ISBN - ↩︎Not very comprehensive, but it is quite readable and goes into some detail about the plants it does cover.
  26. [26]An Illustrated Flora of the Northern United States and Canada — Britton. N. L. Brown. A. · Dover Publications. New York. · 1970 · ISBN 0-486-22642-5 ↩︎Reprint of a 1913 Flora, but still a very useful book.
  27. [27]The American Woods (in 14 volumes) — Hough R.B. · Romeyn B. Hough Co.; New York · 1888 - 1928 · http://www.biodiversitylibrary.org ↩︎Detailed information, with photographs, of the woods of almost 400 species of American trees. It can be downloaded from the Internet.
  28. [PFAF]Plants for a Future — pfaf.org ↩︎