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Plant Focus

Quercus macdougallii
A rare oak endemic to the Sierra Juárez in Oaxaca

Diversity Within Oaks

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Kiran Bargali, Beena Joshi, S.S. Bargali and S.P. Singh

Published May 2014 in International Oaks No. 25: 57–70


In this paper an overview of the range of variations that occur in the genus Quercus (oaks) of the family Fagaceae is given. Oaks are one of the most important groups of flowering plants and dominate large regions of the Northern Hemisphere. We considered oaks from all regions of the world, while focusing on Himalayan oaks. These have not been studied as much by Western workers or by Indian botanists and foresters. With more than 600 species, Quercus is possibly the greatest natural ecosystem-forming genus of the world. Oaks are known for their great variety of growth forms, leaf shape and size, and for their nutrient-rich acorns. Many other trees might exceed the commercial value of oaks, but with regard to biodiversity, they have few parallels in the living world. Outside tropical rainforests, oaks are the greatest biodiversity-centric plants on the planet.


acorns, biodiversity, Himalayan oaks, Quercus, leaf morphology, oak ecology


Abrams, M.D. 1990. Adaptation and responses to drought in Quercus species of North America. Tree Physiology 7: 227-238. Abrams, M.D. 1992. Fire and the development of Oak forest. Bioscience 42: 346-353.

Allen, B.H., B.A. Halzman, and R.R. Evett. 1991. A Classification system for California is hardwood rangelands prepared for strategic planning program, California Dept of Forestry and fire protection unpublished report.

Bargali, K., P. Bisht, A. Khan, and Y.S. Rawat. 2013. Diversity and regeneration status of tree species at Nainital catchment, Uttarakhand,India. International Journal of Biological Conservation 5(5): 270-280.

Bargali, K., and S.S. Bargali. 2000. Nutrient utilization efficiencies of two Central Himalayan species. Journal of Tropical Forest Science 12(3): 450-458.

Bargali, K., S.S. Bargali, and S.P. Singh. 2005. Growth and Competition between Pinus roxburghii and Quercus leucotrichophora Seedlings as Affected by Nutrient and Moisture availability. Bulletin of National Institute of Ecology 15: 181-190.

Barrett, R.H. 1980. Mammals of California Oak habitats - Management implication in proceedings of the symposium on the Ecology, Management, and Utilization of California Oaks, June 26-28, 979. USD Forest Service General Technical Report PSW-44: 275-291.

Bolsinger, C.L. 1988. The hardwood of California is timber lands, woodlands, and savannas USDA. Forest Service Pacific Northwest Research station. Resource Bulletin PNW-RB-148.

Burns, R.M., and B.H. Honkala. 1990. Silvics of North America. Vol.2, Hardwood. USDA Forest Service Agriculture Handbook 654.

Doak, S.C. 1989. Modeling patterns of land use and ownership. Final report to California Department of Forestry and Fire Protection. Contract no. 8CA63967.

Elias, T.S. 1971. The genera of Fagaceae in the south-eastern United States. Journal of the Arnold Arboretum 52: 154-195. Garrison, B. 1996. Vertebrate wildlife species and habitat associations in Standiford, R.B. and P. Tinnin 1996. Guidelines for managing California’ s hardwood rangelands. U.C. Division of Agriculture and Natural Resources Publication. Holmes, T. H. 1990. Botanical Trends in Northern California Oak Woodland. Rangelands 12: 3-7.

Janzen, D.H. 1971. Seed predation by animals. Annual Review of Ecology and Systematics 2: 465-492.

Kaul, R.B. 1986. Evolution and reproduction Biology of inflorescences in Lithocarpus, Castanopsis, Castanea and Quercus (Fagaceae). Annals of Botany 73: 284-296.

Keator, G., and S. Bazell. 1998. The life of an Oak: An intimate portrait. Berkley: Heyday Books and Oakland: California Oak foundation.. 256 pp.

Koenig, W.D., R.L. Mumme, W.J. Carmen, and M.T. Stanback. 1994. Acorn production by oaks in Central Coastal California: variation in and among years. Ecology 75: 99-109.

Lawrence, G.H.M. 1951. Taxonomy of vascular plants. New York: Mac Million Co.,

Mayer, K.E., P.C. Passof, C. Bolsinger, W.W. Grenfall, and H. Slack 1985. Status of the hardwood resource of California : A report  to the Board of Forest California. Dept. of Forestry and Fire Protection, Sacramento. CA 126 pp. Munz, PA., and D.D. Keck. 1959. A California flora. Berkeley: Univ. Calif.  Press. 1681 p.

Negi, A.S., G.C.S. Negi, and S.P. Singh. 1996. Establishment and growth of Quercus floribunda seedling after a mast year. Journal of  Vegetation Science 7:559-564.

Negi, S.S., and H.B. Naithani. 1995. Oaks of India, Nepal and Bhutan. Dehradun: International Book Distributors.

Pacific Meridian Resources. 1994. California Hardwood Rangeland Monitoring. Final report prepared for strategic Planning

Program. California Dep. of Forestry and Fire Protection. unpublished report. Parker, R.N. 1939. Two natural hybrids, The Indian Forester 65: 585-586.

Singh, J.S., and S.P. Singh. 1987. Forest vegetation of the Himalaya. Botanical Review 53: 80-192.

Singh, J.S., and S.P. Singh. 1992. Forests of Himalaya: Structure, Functioning, and Impact of Man. Nainital, India: Gyanodaya Prakashan, 294.

Singh, S.P., Kiran Bargali, A Joshi, and S. Chaudhry. 2005. Nitrogen resorption in leaves of tree and shrub seedlings in response to increasing soil fertility. Current Science 89(2): 389-396.

Soepadmo, E. 1972. Florae Malesianae, I. Reinwardtia 7: 265-403.

Standiford, R.B., D. McCreary, S. Gaerture, and L. Forero. 1996. Sustainability of firewood harvesting on hardwood rangelands accepted for publication in California Agriculture.

Thadani, R. 1999. Disturbance, microclimate and the competitive dynamics of tree seedlings in banj oak (Quercus leucotrichophora) forests of the Central Himalaya, India. Ph.D. Thesis, Yale University, Yale.

Troup, R.S. 1921. The Silviculture of Indian Trees. London: Oxford University Press.

Tucker, J.M. 1974. Patterns of Parallel evolution of leaf forms in new world Oaks. Taxon 23: 129-154.

Zobel, D.B., Jeet Ram ,and S.S. Bargali. 1995. Structural and physiological changes in Quercus leucotrchophora and Pinus roxburghii associated with stand disturbance in the Kumaun Himalaya, India. International Journal of Ecology and Environmental Sciences 21: 45-66.