Index of Species Information

SPECIES:  Rhamnus purshiana


SPECIES: Rhamnus purshiana
AUTHORSHIP AND CITATION : Habeck, R. J. 1992. Rhamnus purshiana. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : RHAPUR SYNONYMS : NO-ENTRY SCS PLANT CODE : RHPU COMMON NAMES : cascara cascara buckthorn cascara sagrada bearberry chittam bark coffee-tree TAXONOMY : The currently accepted scientific name of cascara is Rhamnus purshiana DC. [12]. There are no recognized subspecies, varieties, or forms. LIFE FORM : Tree, Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Rhamnus purshiana
GENERAL DISTRIBUTION : Cascara generally occurs from British Columbia down through northern California. It is mostly distributed west of the Cascades but can also be found east to northern Idaho and northwestern Montana [1,12]. ECOSYSTEMS : FRES20 Douglas-fir FRES21 Ponderosa pine FRES23 Fir - spruce FRES24 Hemlock - Sitka spruce FRES25 Larch FRES27 Redwood FRES28 Western hardwoods FRES34 Chaparral - mountain shrub STATES : CA ID MT OR WA BLM PHYSIOGRAPHIC REGIONS : 1 Northern Pacific Border 2 Cascade Mountains 4 Sierra Mountains 5 Columbia Plateau 8 Northern Rocky Mountains KUCHLER PLANT ASSOCIATIONS : K001 Spruce - cedar - hemlock forest K002 Cedar - hemlock - Douglas-fir forest K003 Silver fir - Douglas-fir forest K005 Mixed conifer forest K010 Ponderosa shrub forest K011 Western ponderosa forest K012 Douglas-fir forest K029 California mixed evergreen forest SAF COVER TYPES : 205 Mountain hemlock 206 Engelmann spruce - subalpine fir 210 Interior Douglas-fir 211 White fir 212 Western larch 221 Red alder 224 Western hemlock 225 Western hemlock - Sitka spruce 226 Coastal true fir - hemlock 227 Western redcedar - western hemlock 228 Western hemlock 229 Pacific Douglas-fir 230 Douglas-fir - western hemlock 233 Oregon white oak 234 Douglas-fir - tanoak - Pacific madrone 237 Interior ponderosa pine SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Cascara is predominately a shrub component on forested sites in the Pacific Northwest. No information was found listing cascara as an understory dominant or site indicator. Cascara was listed, however, as a member of a prairie community occupying a floodplain in the Willamette Valley, Oregon. It was also listed as a representative species in a vine maple (Acer circinatum) plant association on a lava flow near Santiam Pass, Oregon [9]. In southern Oregon, cascara was found as a component in many plant associations in the white fir (Abies concolor), Douglas-fir (Pseudotsuga menziesii), and western hemlock (Tsuga heterophylla) series [2]. Plant associations (pas) in southern Oregon where cascara is listed as a component are as follows [2]: Constancy Min. Max. (pas) (%) % cover % cover Range Mean SD -------------------------------------------------------------------- W. Hemlock Series 2.0 1.0 2.0 1.0 1.2 0.4 TSHE/GASH/LIBO 5.0 --- --- --- 1.0 0 TSHE/PSME/GASH 8.0 --- --- --- 1.0 0 TSHE/GASH-CHUM 25.0 --- --- --- 1.5 0.7 TSHE/ACCI/RUNI 11.0 --- --- --- 1.0 0 White Fir Series 2.0 1.0 8.0 7.0 2.8 3.5 ABCO/ACGL/BENE 10.0 --- --- --- 1.0 0 ABCO/COCOC-AMAL 16.0 --- --- --- 8.0 0 ABCO-CADE3/BENE 4.0 --- --- --- 1.0 0 ABCO-PSME/BEPI 3.0 --- --- --- 1.0 0 Douglas-fir Series 3.0 3.0 3.0 0 3.0 0 PSME/RHDI/CYGR 33.0 --- --- --- 3.0 0 Scientific names for species used above are as follows: ABCO Abies concolor ACCI Acer circinatum ACGL Acer glabrum AMAL Amelanchier alnifolia BENE Berberis nervosa BEPI Berberis piperiana CADE3 Calocedrus decurrens CHUM Chimaphila umbellata COROC Corylus cornuta californica CYGR Cynoglossum grande GASH Gaultheria shallon LIBO Linnaea borealis PSME Pseudotsuga menziesii RHDI Rhus diversiloba RUNI Rubus nivalis TSHE Tsuga heterophylla


SPECIES: Rhamnus purshiana
IMPORTANCE TO LIVESTOCK AND WILDLIFE : Cascara is a wide-spread but not abundant shrub found primarily in forested mountains [27]. It has been listed as a browse species for mule deer in Oregon [7,29] and for elk in northern Idaho [26]. Cascara was found to be a winter browse species for mule deer in northwestern Oregon. Sixty-eight percent of available cascara shrubs were browsed during the winter. In summer, however, cascara was less desirable; only 27 percent of available cascara shrubs were browsed [6]. Other mammals that browse cascara include the Olympic black bear, Oregon gray fox, racoon, and ring-tailed cat [1,29]. Cascara drupes are eaten by five species of birds including the Oregon ruffed grouse and band-tailed pigeon. Cascara is of no value as forage for livestock [30]. How the purgative characteristics of cascara bark and drupes affect wildlife are not known [29]. PALATABILITY : Although utilized by wildlife, cascara is not very palatable. Cascara is browsed very lightly by sheep and to some extent by mule deer, but for all practical purposes its forage value is negligible [27]. Palatability of cascara leaves to elk on the Selway Game Preserve, Idaho was poor [30]. The relish and degree of use shown by wildlife species for cascara in British Columbia are as follows [4]: Specie Palatability ----------------- ------------ bighorn sheep poor elk fair moose poor mule deer poor white-tailed deer poor caribou poor coast deer good NUTRITIONAL VALUE : The nutritive value of cascara is poorly understood. Cascara was found to be nitrogen-rich in one southern British Columbia study [14]. COVER VALUE : Cascara often forms brushy stands capable of providing abundant thermal and hiding cover [2]. The shrubby form may prove a more valuable cover species than the treelike northern form [29]. VALUE FOR REHABILITATION OF DISTURBED SITES : NO-ENTRY OTHER USES AND VALUES : The greatest known value of cascara is its purgative properties. In a single year, five million pounds of dried cascara bark from the Pacific Northwest was processed by pharmaceutical companies in the manufacture of laxatives [1,23]. The Kootenai and Flathead tribes of western Montana used cascara as a laxative, consuming it in the form of a tea brewed from the bark. These Indians believed that it would be a purgative when the bark was stripped downward. If stripped upward, the drug would act as an emetic. Cascara bark contains anthraquinare derivatives, tannin, resins, starch, glucose, and other compounds [11]. When the bark is chewed, it tastes extremely bitter, and may temporarily numb the taste buds [1]. The flesh of some animals which have consumed the drupes is said to retain some of the purgative properties. The juice pressed from the berries is used to prepare a 'syrup of cascara'. The bark and dried berries have been used as a source of yellow- and saffron-colored dyes. The berry juice. when combined with alum, produces a green dye once used by artists [21]. Apparently, if cascara is handled for a long time, the laxatative effects can even be transferred through the skin [1]. For maximum effectiveness, bark collection is recommended from mid-April to the end of August, and bark should be stored as long as possible before being used [11]. OTHER MANAGEMENT CONSIDERATIONS : Disease: Cascara has been found to be susceptible to laboratory exposures of crown rusts [29]. Herbicides: Garlon 4 and Tordon 101 applied during early foliar development top-killed 95 percent of cascara 3 years after treatment [19].


SPECIES: Rhamnus purshiana
GENERAL BOTANICAL CHARACTERISTICS : Cascara is a deciduous, erect, tall shrub or small tree. It can attain a height up to 33 feet (10 m) at maturity, but becomes smaller in size and bushier along its southern distribution [29]. West of the Cascades, it develops a single trunk 8 to 12 inches (20-30 cm) thick, 20 to 35 feet (6-10.7 m) tall. It has greenish-yellow flower petals approximately 0.12 to 0.16 inch (3-4 mm) long [23]. Cascara has a purplish-black drupe about 0.3 inch (7.5 mm) in diameter, containing several seeds [5,20]. Cascara is very tolerant of shade [1]. The leaves are oblong, 3 to 5 inches (7.5-12.5 cm) long, and have 10 to 12 pairs of prominent parallel veins arising directly opposite each other on the midrib. The leaf buds have no scales [12,27]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Cascara usually reproduces by seed. It can also spread by layering and can sometimes be propagated by cuttings. Cascara will coppice after being stripped of bark and cut down [11,29]. Seeds: Cascara generally produces 20 pounds (18 kg) of seeds per 100 pounds (90 kg) of fruit. Cleaned seeds range from 5,000 to 19,000 seeds per pound (4,500-17,100 kg), with an average of 12,300. Recommended sowing depth is 1 inch, with seedbed shading [13]. Birds are the predominant distributors of cascara seeds [1]. Morphological characteristics of cascara fruit from Rainbow Creek Research Natural Area, southeast Washington are as follows [24]: Mean ------ Fruit Diameter (mm) 11.60 Fruit Mass (mg) 796.80 Pulp Dry Mass (mg) 126.10 Number of Seeds per Fruit 3.00 Fresh Seed Mass per Fruit (mg) 165.20 Fresh Pulp Mass (mg) 3.80 SITE CHARACTERISTICS : Cascara generally grows on lower mountain slopes [1]. It may also inhabit moist canyons on the east slope of the Cascades. In Oregon, cascara is generally a moist-site indicator [2]. It is commonly found with red alder (Alnus rubra) on moist bottomlands but is rarely abundant [1]. Site characteristics from southern Oregon Cascade Mountain Province where cascara is found as a forest nominal component are as follows [2]: Range of Means -------------- Elevation (ft): 2,447 - 4,232 Slope (%): 13.0 - 53.0 Soil Depth (in): 34.6 - 46.7 Rooting Depth (in): 39.3 - 50.0 Mean Annual Temp. (F): 43.9 - 48.8 Max. Month Temp. (F): 77.5 - 84.7 Mean Annual ppt (in): 36.7 - 67.5 Dry Season ppt (in): 6.0 - 8.8 Litter (%): 70.7 - 98.7 Moss (%): 2.3 - 45.2 Bareground (%): 0.2 - 4.0 Gravel (%): 0.3 - 3.8 Rock (%): 0.4 - 6.1 Bedrock (%): 0.0 - 3.8 SUCCESSIONAL STATUS : Cascara has not been cited as a dominant species in any forest habitat type described for the Pacific Northwest. Being shade tolerant, it is often found in the understory of second-growth forests [1]. Therefore, its primary role seems to be that of a long-lived invader species. SEASONAL DEVELOPMENT : Major phenological activities of cascara in northern Idaho are as follows [22]: Bud Leafing Stem Fruit Leaf Color Leaf Year Swell Out Growth Blooming Growth Change Fall ------------------------------------------------------------------------ 1971 NA-4/27 5/4-5/19 5/11-7/21 5/26-6/9 6/18-NA 9/30 NA 1972 4/19/5/6 5/6-6/2 5/19-7/12 5/22-6/13 6/20-NA 10/9 NA 1973 NA-4/23 5/2-6/4 5/2-7/4 5/28-6/12 6/19-NA 10/2 NA


SPECIES: Rhamnus purshiana
FIRE ECOLOGY OR ADAPTATIONS : Cascara will sprout from the root crown following low-intensity fires [11,29]. POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving root crown or caudex secondary colonizer; off-site seed carried to site after year 2


SPECIES: Rhamnus purshiana
IMMEDIATE FIRE EFFECT ON PLANT : Cascara is usually top-killed by fire [29]. Preburn and postburn measurements of cascara in central Idaho were as follows [17]: Avg. Live Avg. Live Avg. Crown Avg. Dead No. Avg. Sprout Crown Diameter Crown Height Below 7ft. Crown Basal Height (ft) (ft) (%) (%) Sprouts (ft) ------------------------------------------------------------------------------ Preburn 4.0 8.0 95.0 95.0 1.0 1.5 Postburn 3.0 4.5 100.0 100.0 18.0 3.0 ------------------------------------------------------------------------------ 1. Preburn measurements were taken in March, 1965. Postburn measurements were taken in August, 1965. 2. Postburn measurements were taken on the part of the plant which existed before treatment. 3. All cascara's aboveground parts were completely killed by the fire. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Change in cascara measurements after prescribed burns in northern Idaho were as follows [16]: 1965 1970 1975 1966 1971 1976 ------------------------------------------- Avg. Preburn Crown Height (cm): 244 --- --- --- --- --- Avg. Preburn Crown Diameters (cm): 91 --- --- --- --- --- Avg. No. Basal Sprouts per Plant: 18 12 7 --- --- --- Avg. Sprout Height (cm): 91 76 76 --- --- --- Max. Crown Height 2 Years After Burn (cm): --- --- --- 183 137 122 Max. Crown Diameter 2 Years After Burn (cm): --- --- --- 137 107 107 DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Fire intervals on southern Oregon sites where cascara occurs range from 30 to 60 years, to longer intervals of 100 to 320 years. These understories are generally free from heavy fuels, giving rise to low-intensity fires. In some plant associations that include cascara, however, high-intensity, stand-replacing fires occur approximately every 60 to 150 years [2].


SPECIES: Rhamnus purshiana
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Forage availability in relation to browsing of Douglas-fir seedlings by black-tailed deer. Journal of Wildlife Management. 32(3): 542-553. [16105] 7. Einarsen, Arthur S. 1946. Crude protein determination of deer food as an applied management technique. Transactions, 11th North American Wildlife Conference. 11: 309-312. [17031] 8. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905] 9. Franklin, Jerry F.; Dyrness, C. T. 1973. Natural vegetation of Oregon and Washington. Gen. Tech. Rep. PNW-8. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 417 p. [961] 10. 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] 11. Hart, J. 1976. Montana--native plants and early peoples. Helena, MT: Montana Historical Society. 75 p. [9979] 12. Hitchcock, C. Leo; Cronquist, Arthur. 1973. Flora of the Pacific Northwest. Seattle, WA: University of Washington Press. 730 p. [1168] 13. Hubbard, Richard L. 1974. Rhamnus L. Buckthorn. In: Schopmeyer, C. S., ed. Seeds of woody plants in the United States. Agriculture Handbook No. 450. Washington: U. S. Department of Agriculture, Forest Service: 704-708. [7738] 14. Klinka, K.; Wang, Q.; Carter, R. E. 1990. Relationships among humus forms, forest floor nutrient properties, and understory vegetation. Forest Science. 36(3): 564-581. [13012] 15. 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] 16. Leege, Thomas A. 1979. Effects of repeated prescribed burns on northern Idaho elk browse. Northwest Science. 53(2): 107-113. [5116] 17. Leege, Thomas A.; Hickey, William O. 1966. Lochsa elk study. Big Game Surveys and Investigations: W 85-R-17, Job No. 8. July 1, 1965 to June 30, 1966. Boise, ID: State of Idaho Fish and Game Department. 22 p. [16759] 18. 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] 19. Miller, Daniel L.; Kidd, Frank A. 1983. Shrub control in the Inland Northwest--a summary of herbicide test results. Forestry Research Note RN-83-4. Lewiston, ID: Potlatch Corporation. 49 p. [7861] 20. Morris, Melvin S.; Schmautz, Jack E.; Stickney, Peter F. 1962. Winter field key to the native shrubs of Montana. Bulletin No. 23. Missoula, MT: Montana State University, Montana Forest and Conservation Experiment Station. 70 p. [17063] 21. Mozingo, Hugh N. 1987. Shrubs of the Great Basin: A natural history. Reno, NV: University of Nevada Press. 342 p. [1702] 22. Orme, Mark L.; Leege, Thomas A. 1980. Phenology of shrubs on a north Idaho elk range. Northwest Science. 54(3): 187-198. [1800] 23. Patterson, Patricia A.; Neiman, Kenneth E.; Tonn, Jonalea. 1985. Field guide to forest plants of northern Idaho. Gen. Tech. Rep. INT-180. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 246 p. [1839] 24. Piper, Jon K. 1986. Seasonality of fruit characters and seed removal by birds. Oikos. 46: 303-310. [15348] 25. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843] 26. Trout, Lester C.; Leege, Thomas A. 1971. Are the northern Idaho elk herds doomed?. Idaho Wildlife Review. Nov-Dec: 3-6. [16731] 27. U.S. Department of Agriculture, Forest Service. 1937. Range plant handbook. Washington, DC. 532 p. [2387] 28. 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] 29. 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] 30. Young, Vernon A.; Robinette, W. Leslie. 1939. A study of the range habits of elk on the Selway Game Preserve. Bull. No. 9. Moscow, ID: University of Idaho, School of Forestry. 47 p. [6831]

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