Index of Species Information

SPECIES:  Aesculus californica


SPECIES: Aesculus californica
AUTHORSHIP AND CITATION : Howard, Janet L. 1992. Aesculus californica. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : AESCAL SYNONYMS : Calothyrsus californica SCS PLANT CODE : AECA COMMON NAMES : California buckeye buckeye horsechestnut TAXONOMY : The currently accepted scientific name of California buckeye is Aesculus californica (Spach) Nutt. [18,21]. There are no recognized subspecies, varieties, or forms. LIFE FORM : Tree, Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Aesculus californica
GENERAL DISTRIBUTION : California buckeye is emdemic to California. It occurs in the the Klamath and Coast Ranges from Siskiyou County County south to Los Angeles County. In the Cascade Range and the foothills of the Sierra Nevada, it occurs from from Shasta County south to Kern County. California buckeye is occasionally found in the Central Valley in Yolo, Colusa, and Stanislaus Counties [5]. ECOSYSTEMS : FRES20 Douglas-fir FRES21 Ponderosa pine FRES27 Redwood FRES28 Western hardwoods FRES34 Chaparral - mountain shrub STATES : CA BLM PHYSIOGRAPHIC REGIONS : 3 Southern Pacific Border 4 Sierra Mountains 7 Lower Basin and Range KUCHLER PLANT ASSOCIATIONS : K003 Silver fir - Douglas-fir forest K005 Mixed conifer forest K006 Redwood forest K009 Pine - cypress forest K010 Ponderosa shrub forest K029 California mixed evergreen forest K030 California oakwoods K033 Chaparral K034 Montane chaparral SAF COVER TYPES : 229 Pacific Douglas-fir 231 Port-Orford-cedar 232 Redwood 234 Douglas-fir - tanoak - Pacific madrone 243 Sierra Nevada mixed conifer 244 Pacific ponderosa pine - Douglas-fir 245 Pacific ponderosa pine 246 California black oak 247 Jeffrey pine 248 Knobcone pine 249 Canyon live oak 250 Blue oak - Digger pine 255 California coast live oak SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : California buckeye woodland is recognized as a distinct plant community [13]. The species may also codominate oak (Quercus spp.) woodland. Interior live oak (Q. wislizenii) and blue oak (Q. douglasii) are the most common codominants of oak woodland [1,2,3,22,23]. In chaparral, it is sometimes a dominant shrub or tree [2,4]. The following published classification schemes list California buckeye as a climax species or a dominant part of the vegetation in community types (cts) or plant associations (pas): Area Classification Authority CA: Coast Ranges mixed oak cts Allen & others 1991 w foothills Sierra Nevada foothill woodland pas Thorne 1976 Klamath Mts. northern mixed Holland 1986 chaparral pas Pinnacles National Monument Ca buckeye woodland cts Halverson & Clark 1986


SPECIES: Aesculus californica
WOOD PRODUCTS VALUE : California buckeye is occasionally used for lumber and paper pulp [25]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : California buckeye is toxic to all classes of livestock and wildlife. The bark, leaves, stems, fruits, and seeds all contain glycosidal compounds which cause haemolytic action on red blood cells and depress the central nervous system when ingested. This species has been implicated in inducing abortion in cattle [5,18]. PALATABILITY : Despite its toxicity, California buckeye flowers, leaves, and shoots are palatable to livestock and wildlife. Hedrick [14] has listed it among the 20 chaparral browse plants most preferred by cattle and black-tailed deer. The palatability of the seeds for black-tailed deer, rodents, and Stellar's jay is fair to poor [5]. NUTRITIONAL VALUE : The dry matter composition of California buckeye seeds is 80 percent carbohydrate, 5 percent protein, 1 percent fat, 2 percent ash, 3 percent fiber, and 9 percent miscellaneous [12]. Protein content of the leaves and stems varies from 31 percent in April to 5 percent in October [6]. Carbohydrate content of leaves and stems varies from 50 percent in April to 1 percent in October [20]. Since California buckeye is a systemic poison, how much of this nutrition is actually metabolized by seed-eating or browsing livestock and wildlife in unknown. (see Importance to Livestock and Wildlife). COVER VALUE : The cover value of California buckeye is poor from late spring through late winter due to early leaf fall. VALUE FOR REHABILITATION OF DISTURBED SITES : California buckeye is valuable as a soil binder on stream or river banks and on steep slopes [11,17,26]. Seed can be obtained by harvesting native plants. Seed propagation methods have been detailed [20,24]. OTHER USES AND VALUES : California buckeye is used as a landscaping ornamental [24]. The seeds of California buckeye served as a staple for California Indians, who would mash the roasted seeds and then leach them to remove the poison [5]. Native Americans also secured the seeds in streams and other waterways in order to stupefy fish for easy capture [21]. OTHER MANAGEMENT CONSIDERATIONS : Grazing: California buckeye often considered undesirable on rangeland because of its toxicity. Apian considerations: Honeybees are the chief pollinators of California buckeye, but the pollen and nectar are toxic to them [5,9,14]. Losses of adult honeybees and their larvae due to poisoning can be severe [9]. Human beings have been poisoned by eating honey made from California buckeye [18]. Control treatments: California buckeye is susceptible to spray or injection/cut surface treatments of phenoxy herbicides and picloram [7,14,27]. Hand or mechanical brush control is ineffective unless the root crown is removed [25,28].


SPECIES: Aesculus californica
GENERAL BOTANICAL CHARACTERISTICS : California buckeye is a large shrub or tree up to 23 feet (7 m) tall. The 2-to 6-inch-long (5-15 cm) leaves are deciduous and palmately compound [21]. Flowers are borne on a terminal panicle 4 to 8 inches (10-20 cm) long. The pear-shaped, light brown fruit contains one to six glossy brown seeds 0.8 to 1.2 inches (2-3 cm) in diameter [5,21]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Sexual: California buckeye reproduces by seed [5]. The average tree produces approximately 100 seeds per year. Seed dispersal is poor and is accomplished mainly by gravity or water; dispersal by animals is rare [13]. Seeds are viable for only 1 year and are shed from November to mid-February [24]. Germination occurs within several weeks of shedding if the soil temperature is above 40 degrees Fahrenheit (4 degrees C). If the temperature persists below 40 degrees for 2 months or more the seeds are susceptible to fungal infections or desiccation [12]. Germination success rates of 75 percent have been reported under laboratory conditions [19]. Asexual: California buckeye can sprout from the stump or root crown [3,28]. SITE CHARACTERISTICS : California buckeye grows on dry slopes, in canyons, and along waterways [5,21]. In the Central Valley it occurs along stream and river banks [5,19]. It is associated with poison-oak (Toxicodendron diversilobum) in most communities in which it occurs [5,17]. Soil: California buckeye grows in sandy, sandy-loam, or gravelly-loam soils [5]. Climate: California buckeye occurs in a Mediterranean climate with cool moist winters and hot dry summers [5,15,18]. The mean annual rainfall is less than 14 inches, and temperatures are in excess of 100 degrees Fahrenheit (38 degrees C) for several successive days every summer [14]. Elevation: California buckeye occurs below 4,000 feet (1,219 m) [21]. SUCCESSIONAL STATUS : California buckeye exhibits both tolerant and intolerant characteristics. It occurs as a widely scattered individuals in open grasslands. It also occurs as an understory shrub in mixed evergreen forest [3]. It is a climax indicator in chaparral and mixed oak communities [1] and in California buckeye woodlands [8]. SEASONAL DEVELOPMENT : California buckeye flowers from April to September [24]. New leaves emerge from March to June while soil moisture is abundant [20]. The leaves dry up and are shed in late spring or early summer in Sierra Nevada foothill populations but may be retained through fall in coastal populations when soil moisture remains available [5]. Fruits ripen from September to October and are dropped from November to December [24].


SPECIES: Aesculus californica
FIRE ECOLOGY OR ADAPTATIONS : Plant adaptations: California buckeye sprouts from the root crown after aboveground portions of the plant have been damaged [5,28]. Seeds would probably not survive fire because they are highly susceptible to desiccation by heat [8]. Seed is often transported by water and could be carried to a burn site in that manner [13]. Fire ecology: Early leaf fall results in accumulation of dry litter around the plant early in the fire season. POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving root crown or caudex off-site colonizer; seed carried by animals or water; postfire yr 1&2 secondary colonizer; off-site seed carried to site after year 2


SPECIES: Aesculus californica
IMMEDIATE FIRE EFFECT ON PLANT : Fire top-kills California buckeye [25]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Information regarding California buckeye's response to fire is limited. Sampson [25] has said that sprouting chaparral brush species, including California buckeye, recover rapidly following a fire, sending out new shoots during the first growing season. Growth in subsequent seasons is also rapid, with the plant sometimes exceeding its prefire mass within a few years. Sprouting can occur within a few weeks following fire, even in the summer months. Growth is supported by drawing on food and water reserves in the fully developed root system [20]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Grazing considerations: California buckeye cannot be successfully eliminated by prescribed burning. Fire will bring it under control if the area is reburned every 7 to 8 years and immediately reseeded with herbaceous vegetation [14]. Otherwise, California buckeye will recover at the expense of more desirable herbaceous plants [14,25].


SPECIES: Aesculus californica
REFERENCES : REFERENCES : 1. Allen, Barbara H.; Holzman, Barbara A.; Evett, Rand R. 1991. A classification system for California's hardwood rangelands. Hilgardia. 59(2): 1-45. [17371] 2. Baker, Gail A.; Rundel, Philip W.; Parsons, David J. 1981. Ecological relationships of Quercus douglasii (Fagaceae) in the foothill zone of Sequoia National Park, California. Madrono. 28(1): 1-12. [6477] 3. Baker, G. A.; Rundel, P. W.; Parsons, D. J. 1982. Comparative phenology and growth in three chaparral shrubs. Botanical Gazette. 143(1): 94-100. [6533] 4. Barbour, Michael G. 1987. Community ecology and distribution of California hardwood forests and woodlands. In: Plumb, Timothy R.; Pillsbury, Norman H., technical coordinators. Proceedings of the symposium on multiple-use management of California's hardwood resources; 1986 November 12-14; San Luis Obispo, CA. Gen. Tech. Rep. PSW-100. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station: 18-25. [5356] 5. Holmer, L.; Nitare, L.; Stenlid, J. 1994. Population structure and decay pattern of Phellinus tremulae in Populus tremula as determined by somatic incompatibility. Canadian Journal of Botany. 72: 1391-1396. [24510] 6. Bissell, Harold D.; Strong, Helen. 1955. The crude protein variations in the browse diet of California deer. California Fish and Game. 41(2): 145-155. [10524] 7. Bovey, Rodney W. 1977. Response of selected woody plants in the United States to herbicides. Agric. Handb. 493. Washington, DC: U.S. Department of Agriculture, Agricultural Research Service. 101 p. [8899] 8. Buckman, Robert E. 1964. Effects of prescribed burning on hazel in Minnesota. Ecology. 45(3): 626-629. [12204] 9. Clark, Harold W. 1937. Association types in the North Coast Ranges of California. Ecology. 18: 214-230. [11187] 10. Dayton, William A. 1931. Important western browse plants. Misc. Publ. 101. Washington, DC: U.S. Department of Agriculture. 214 p. [768] 11. Goldner, Bernard H. 1984. Riparian restoration efforts associated with structurally modified flood control channels. In: Warner, Richard E.; Hendrix, Kathleen M., eds. California riparian systems: Ecology, conservation, and productive management: Proceedings of the conference; 1981 September 17-19; Davis, CA. Berkeley, CA: University of California Press: 445-451. [5852] 12. Gordon, Aaron; Sampson, Arthur W. 1939. Composition of common California foothill plants as a factor in range management. Bull. 627. Berkeley, CA: University of California, College of Agriculture, Agricultural Experiment Station. 95 p. [3864] 13. Halvorson, William L.; Clark, Ronilee A. 1989. Vegetation and floristics of Pinnacles National Monument. Tech. Rep. No. 34. Davis, CA: University of California at Davis, Institute of Ecology, Cooperative National Park Resources Study Unit. 113 p. [11883] 14. Hedrick, Donald W. 1951. Studies on the succession and manipulation of chamise brushlands in California. College Station, TX: Texas Agricultural and Mechanical College. 113 p. Dissertation. [8525] 15. Holland, Robert F. 1986. Preliminary descriptions of the terrestrial natural communities of California. Sacramento, CA: California Department of Fish and Game. 156 p. [12756] 16. Holmes, Tyson H. 1990. Botanical trends in northern California oak woodland. Rangelands. 12(1): 3-7. [10939] 17. Katibah, Edwin F.; Nedeff, Nicole E.; Dummer, Kevin J. 1984. Summary of riparian vegetation aerial and linear extent measurements from the Central Valley Riparian Mapping Project. In: Warner, Richard E.; Hendrix, Kathleen M., eds. California riparian systems: Ecology, conservation, and productive management: Proceedings of the conference; 1981 September 17-19; Davis, CA. Berkeley, CA: University of California Press: 46-50. [5824] 18. Little, Elbert L., Jr. 1976. Atlas of United States trees. Volume 3. Minor western hardwoods. Misc. Publ. 1314. Washington, DC: U.S. Department of Agriculture, Forest Service. 13 p. 290 maps. [10430] 19. Mirov, N. T.; Kraebel, C. J. 1937. Collecting and propagating the seeds of California wild plants. Res. Note No. 18. Berkeley, CA: U.S. Department of Agriculture, Forest Service, California Forest and Range Experiment Station. 27 p. [9787] 20. Mooney, H. A.; Hayes, R. I. 1973. Carbohydrate storage cycles in two Californian Mediterranean-climate trees. Flora. 162: 295-304. [10525] 21. Munz, Philip A. 1973. A California flora and supplement. Berkeley, CA: University of California Press. 1905 p. [6155] 22. Parsons, David J. 1981. The historical role of fire in the foothill communities of Sequoia National Park. Madrono. 28(3): 111-120. [13586] 23. Ratliff, Raymond D.; Duncan, Don A.; Westfall, Stanley E. 1991. California oak-woodland overstory species affect herbage understory: management implications. Journal of Range Management. 44(4): 306-310. [16118] 24. Rudolf, Paul O. 1974. Aesculus L. buckeye, horsechestnut. In: Schopmeyer, C. S., technical coordinator. Seeds of woody plants in the United States. Agric. Handb. 450. Washington, DC: U.S. Department of Agriculture, Forest Service: 195-200. [7475] 25. Sampson, Arthur W. 1944. Plant succession on burned chaparral lands in northern California. Bull. 65. Berkeley, CA: University of California, College of Agriculture, Agricultural Experiment Station. 144 p. [2050] 26. Stromberg, Laurence P.; Katibah, Edwin F. 1984. An application of the spatial-aggregation method to the description of riparian vegetation. In: Warner, Richard E.; Hendrix, Kathleen M., eds. California riparian systems: Ecology, conservation, and productive management: Proceedings of a conference; 1981 September 17-19; Davis, CA. Berkeley, CA: University of California Press: 347-355. [5839] 27. U.S. Department of Agriculture, Forest Service, Northern Region.. 1973. U.S. Department of Agriculture, Forest Service, environmental statement, final: the use of herbicides in vegetation management. Unpublished draft supplied by Steve Yurich, Regional Forester, U.S. Department of Agriculture, Forest Service, Region 1. [2380] 28. Van Dersal, William R. 1938. Native woody plants of the United States, their erosion-control and wildlife values. Washington, DC: U.S. Department of Agriculture. 362 p. [4240] 29. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434] 30. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905] 31. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998] 32. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation of the conterminous United States. Special Publication No. 36. New York: American Geographical Society. 77 p. [1384] 33. Lyon, L. Jack; Stickney, Peter F. 1976. Early vegetal succession following large northern Rocky Mountain wildfires. In: Proceedings, Tall Timbers fire ecology conference and Intermountain Fire Research Council fire and land management symposium; 1974 October 8-10; Missoula, MT. No. 14. Tallahassee, FL: Tall Timbers Research Station: 355-373. [1496] 34. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843] 35. U.S. Department of Agriculture, Soil Conservation Service. 1982. National list of scientific plant names. Vol. 1. List of plant names. SCS-TP-159. Washington, DC. 416 p. [11573]

FEIS Home Page