Index of Species Information

SPECIES:  Juglans major


Introductory

SPECIES: Juglans major
AUTHORSHIP AND CITATION : Pavek, Diane S. 1993. Juglans major. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ [].

ABBREVIATION : JUGMAJ SYNONYMS : Juglans rupestris Engelm. var. major Torr. [24,29] SCS PLANT CODE : JUMA COMMON NAMES : Arizona walnut Arizona black walnut nogal TAXONOMY : The currently accepted scientific name of Arizona walnut is Juglans major (Torr.) Heller. It is a member of the walnut family (Juglandaceae) [13,46]. Two varieties are currently recognized: J. m. var. major J. m. var. stewartii M. Johnst. [56]. Arizona walnut hybridizes with Juglans microcarpa Berl. in the Trans-Pecos region of Texas [56]. LIFE FORM : Tree FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


DISTRIBUTION AND OCCURRENCE

SPECIES: Juglans major
GENERAL DISTRIBUTION : The range of Arizona walnut extends from central Texas westward to southwestern New Mexico and central Arizona [13,24,29]. Its distribution continues southward into northern Mexico, where it is found from eastern Sonora to western Coahuila [30,46]. Several authors [41,44,56] reported that Arizona walnut was found in Colorado; however, Harrington [23] stated that no specimens had been found to support this range extension. ECOSYSTEMS : FRES21 Ponderosa pine FRES28 Western hardwoods FRES33 Southwestern shrubsteppe FRES34 Chaparral - mountain shrub FRES35 Pinyon - juniper STATES : AZ NM TX MEXICO BLM PHYSIOGRAPHIC REGIONS : 7 Lower Basin and Range 12 Colorado Plateau 13 Rocky Mountain Piedmont KUCHLER PLANT ASSOCIATIONS : K018 Pine - Douglas-fir forest K019 Arizona pine forest K023 Juniper - pinyon woodland K027 Mesquite bosque K031 Oak - juniper woodlands K033 Chaparral SAF COVER TYPES : 210 Interior Douglas-fir 211 White fir 217 Aspen 235 Cottonwood - willow 237 Interior ponderosa pine 239 Pinyon - juniper 240 Arizona cypress 241 Western live oak 242 Mesquite SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Arizona walnut occurs in pure or mixed stands or as scattered individuals. It is dominant or codominant in the southwestern or interior deciduous broad-leaved habitat series with Arizona sycamore (Platanus wrightii), Fremont cottonwood (Populus fremontii), velvet ash (Fraxinus velutina), and western soapberry (Sapindus saponaria var. drummondii) [27,28,31,43,53]. Arizona walnut is an indicator species in the mixed conifer series in ponderosa pine (Pinus ponderosa), white fir (Abies concolor), Douglas-fir (Pseudotsuga menziesii), and quaking aspen (Populus tremuloides) habitat types [2,3,19,21]. Additionally, in southwestern oak woodlands or chaparral, Arizona walnut is seral throughout the Emory oak (Quercus emoryi) series and is a minor component of Gambel oak (Quercus gambelii) community type [3,25,34]. Some of the publications that list Arizona walnut as a dominant or indicator species include: (1) Classification of riparian vegetation [16] (2) Classification of mixed broadleaf riparian forest in Tonto National Forest [27] (3) A forest habitat type classification of southern Arizona and its relationship to forests of the Sierra Madre Occidental of Mexico [37] (4) Classification of riparian habitat in the Southwest [39] (5) Riparian forest and scrubland community types of Arizona and New Mexico [52]. Species associated with Arizona walnut that were not previously mentioned in Distribution and Occurrence information are canyon grape (Vitis arizonica), deergrass (Muhlenbergia rigens), and common hoarhound (Marrubium vulgare) [33,52].

MANAGEMENT CONSIDERATIONS

SPECIES: Juglans major
WOOD PRODUCTS VALUE : Arizona walnut is not an important timber tree due to its limited distribution and small bole size [17]. Its durable wood is suitable for furniture, gunstocks, veneer, and fenceposts [4,29,41,56]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Arizona walnut provides habitat or food to wildlife [9]. Squirrels, birds, and other wildlife consume its fruits [17,56]. Squirrels eat the fruits immediately and do not cache them [48]. Arizona walnut communities have high species richness of breeding birds [51]. PALATABILITY : Arizona walnut is the least desirable species for cattle browsing in southeastern Arizona riparian areas [45]. NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : The branches and trunks of Arizona walnut provide cavities to acorn woodpeckers in riparian bottoms and drainages of southeastern Arizona [38]. VALUE FOR REHABILITATION OF DISTURBED SITES : NO-ENTRY OTHER USES AND VALUES : Arizona walnut is valued as a shade tree [17,29]. Throughout its range, the fruits are gathered and eaten by people [4,29,41]. OHER MANAGEMENT CONSIDERATIONS : Arizona walnut may compete with marketable timber species following the harvest of mixed conifer stands in Arizona. In an Arizona reforestation project, herbicide treatment of Arizona walnut gave limited (16 percent) control [14]. Even though Arizona walnut is sometimes a community dominant, it usually is present in low densities or frequencies [48]. Arizona walnut densities in south-central Arizona riparian areas may be as low as one tree per 1,345.5 square feet (125 sq m), with maximum basal areas of 27.8 square inches per 1,345.5 square feet (179.4 sq cm/125 sq m) [54]. Vegetative propagation of Arizona walnut by stem cuttings and tissue culture has not been successful [40]. Arizona walnut fruits were evaluated for use as a multipurpose energy producing crop in arid areas. Yields of oils and other organic compounds from the fruits were reasonable and warrant further study [12]. Arizona walnut is highly susceptible to walnut anthracnose (Gnomonia leptostyla) which defoliates trees [6]. This fungus transmits easily to commercial walnut cultivars. Arizona walnut seedlings are susceptible to root and crown rots [32].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Juglans major
GENERAL BOTANICAL CHARACTERISTICS : Arizona walnut is a native, deciduous, small to medium tree that may grow up to 65.6 feet (20 m) tall and to 4 feet (1.2 m) in diameter [4,24,44,46]. The stout branches spread widely and form a rounded crown. Pinnately compound leaves are 7 to 14 inches (17.8-35.6 cm) long [13,29]. Arizona walnut is monoecious with separate staminate and pistillate catkins [44,56]. The fruit is 1 to 1.5 inches (2.5-3.8 cm) in diameter with a husk and a thick, hard shell surrounding a single seed [29,46]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Arizona walnut reproduces sexually. It produces large amounts of fruits every 2 to 3 years [41,56]. Periodic crops are attributed to the need for above-average spring precipitation for seed production [50]. Female flower production decreases during times of stress, for example, during drought years [49]. Seedlings grow rapidly and have a well-developed taproot [56]. Beyond the seedling stage, Arizona walnut grows relatively slowly at 1 foot per year (0.3 m/yr) until it reaches maturity [12,45]. Arizona walnut is long-lived and may reach 400 years old [17]. Some seed predation occurs; moderate amounts of seed are consumed by Arizona gray squirrel [48,50]. Germination rates of Arizona walnut are usually less than 50 percent [17,56]. Seeds germinate in the shell during the year following production [9,48]. Buried seeds had higher germination rates than seeds lying on the soil surface [48]. Seed viability increases as seed size increases; however, seed weight declines as trees become larger and older [50]. Germination rate is influenced by light. Arizona walnut germination was lower under dense herb cover than under open canopy cover [48]. High densities of Arizona walnut occurred in stands with a sparse overstory canopy cover in southwestern New Mexico [33]. Arizona walnut seedlings establish over wide elevational and moisture gradients from wet streambanks to dry hillsides [50]. Seedlings are susceptible to drought. In a central Arizona study where drought occurred annually, only one seedling from a cohort of 374 was alive after 2 years [48]. Seedling recruitment is decreased by grazing and flooding [45]. SITE CHARACTERISTICS : Arizona walnut is the only walnut to occur in the desert; it is a facultative riparian species [4,50]. It occurs along ephemeral streams with subsurface flows or perennial streams in moist sites that are occasionally flooded [8,10,21,27,36]. Arizona walnut also is found scattered along river bottoms, canyons, floodplains, dry terraces and hillsides [28,35,49]. It occurs at elevations from 2,600 to 6,500 feet (800-1,981 m) and may extend up to 8,200 feet (2,500 m) in elevation [11,49,53]. The alluvial soils that Arizona walnut commonly occurs on have a wide range of textures; they are often coarse, rocky, or cobbly sandy loams [4,20,21,34]. The soils often are stratified and may be up to 28 feet (8.5 m) deep [11,33]. Two examples of epipedons that Arizona walnut can occur on in southwestern New Mexico are mollic soils on terraces and aquic soils in active channel zones [33]. The nutrient status of the soils is variable; organic matter is usually low due to the coarse textures and frequent flooding [1]. SUCCESSIONAL STATUS : Facultative Seral Species Arizona walnut occurs in various seral stages from early to climax. It is present in early seral riparian communities following periodic flooding disturances such as scouring. Arizona walnut may be seral to or climax with any of the species in the mixed broadleaf and coniferous communities [3,33]. It is relatively shade tolerant [33,48]. SEASONAL DEVELOPMENT : The flowers of Arizona walnut appear shortly before or after the leaves in the spring [4,9,44]. Fruits mature in 3 months. Depending upon elevation, fruits ripen from July to September [50].

FIRE ECOLOGY

SPECIES: Juglans major
FIRE ECOLOGY OR ADAPTATIONS : Arizona walnut has few adaptations to fire. Arizona walnut occurs predominantly in montane riparian woodlands which probably burn infrequently. Although no reference to Arizona walnut seed survival following fire was found in the literature, the thick shell and tendency to germinate better when covered by soil may allow some onsite seeds to survive. A covering of moist soil may offer Arizona walnut seeds some degree of insulation from fire. POSTFIRE REGENERATION STRATEGY : Tree without adventitious-bud root crown Secondary colonizer - off-site seed

FIRE EFFECTS

SPECIES: Juglans major
IMMEDIATE FIRE EFFECT ON PLANT : Arizona walnut is probably killed by fire. Wildfire in a central Arizona riparian woodland killed mature Arizona walnut [7]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Very little is known about the response of Arizona walnut to fire. Although no report of Arizona walnut sprouting was found in the literature, other Juglans species sprout after fire. Following top-kill, surviving small or young trees or saplings of butternut (J. cinerea) and black walnut (J. nigra) may sprout from the root collar or higher on the trunk [58,59]. The age of sprouting individuals was not mentioned for southern California walnut (J. californica) which sprouts from the root collar or basal platform following top-kill [57]. No sprouting information was available for another western species, little walnut (J. microcarpa). If Arizona walnut populations do not sprout, rates of establishment will vary depending on the proximity of seed trees. Without animals facilitating seed dispersal (i.e., squirrels do not cache fruits), colonization rates of Arizona walnut may be slow. Following a 1959 wildfire that burned all of the Three Bar experimental watersheds in central Arizona, a shrub control program using herbicides was established to create perennial stream flows. Arizona walnut was not present before the treatments. Twenty-four years after burning, small amounts of Arizona walnut were found in the untreated stream channel downstream from the treatment area. It did not occur on the untreated control area which had also burned in 1959. No suggestions were made by the authors about the source of the Arizona walnut [15]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Prescribed burning is not recommended for the established southwestern riparian woodlands that Arizona walnut occurs in because fire is difficult to manage in this habitat [7].

REFERENCES

SPECIES: Juglans major
REFERENCES : 1. Alexander, Billy G., Jr.; Ronco, Frank, Jr.; Fitzhugh, E. Lee; Ludwig, John A. 1984. A classification of forest habitat types of the Lincoln National Forest, New Mexico. Gen. Tech. Rep. RM-104. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 29 p. [300] 2. Alexander, Robert R.; Ronco, Frank, Jr. 1987. Classification of the forest vegetation on the National Forests of Arizona and New Mexico. Res. Note RM-469. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 10 p. [3515] 3. Bassett, R.; Larson, M.; Moir, W. 1987. Forest and woodland habitat types (plant associations) of Arizona south of the Mogollon Rim and southwestern New Mexico. 2nd Edition. Albuquerque, NM: U.S. Department of Agriculture, Forest Service, Southwestern Region. [Pages unknown]. [20308] 4. Benson, Lyman; Darrow, Robert A. 1981. The trees and shrubs of the Southwestern deserts. Tucson, AZ: The University of Arizona Press. [18066] 5. 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] 6. Black, W. M.; Neely, Dan. 1978. Relative resistance of Junglans species and hybrids to walnut anthracnose. Plant Disease Reporter. 62(6): 497-499. [11559] 7. Bock, Carl E.; Bock, Jane H. 1990. Effects of fire on wildlife in southwestern lowland habitats. In: Krammes, J. S., technical coordinator. Effects of fire management of Southwestern natural resources: Proceedings of the symposium; 1988 November 15-17; Tucson, AZ. Gen. Tech. Rep. RM-191. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 50-64. [11273] 8. Brian, Nancy J. 1992. Historical review of water flow and riparian vegetation at Walnut Canyon National Monument, Arizona. Tech. Rep. NPS/WRUA/NRTR-92/44. Tuscon, AZ: The University of Arizona, School of Renewable Natural Resources, Cooperative National Park Resources Studies Unit. 39 p. [19870] 9. Brinkman, Kenneth A. 1974. Juglans L. walnut. In: Schopmeyer, C. S., ed. Seeds of woody plants in the United States. Agric. Handb. 450. Washington, DC: U.S. Department of Agriculture, Forest Service: 454-459. [7684] 10. Brown, David E.; Lowe, Charles H.; Hausler, Janet F. 1977. Southwestern riparian communities: their biotic importance and management in Arizona. In: Johnson, R. Roy; Jones, Dale A., tech. coords. Importance, preservation and management of riparian habitat: a symposium: Proceedings; 1977 July 9; Tucson, AZ. Gen. Tech. Rep. RM-43. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment 201-211. [5348] 11. Campbell, C. J. 1973. Pressure bomb measurements indicate water availability in a southwestern riparian community. Res. Note RM-246. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 4 p. [11155] 12. Carr, Merle E.; Mason, Charles T., Jr.; Bagby, Marvin O. 1986. Renewable resources from Arizona trees and shrubs. Forest Ecology and Management. 16: 155-167. [3053] 13. Correll, Donovan S.; Johnston, Marshall C. 1970. Manual of the vascular plants of Texas. Renner, TX: Texas Research Foundation. 1881 p. [4003] 14. Davis, E. A.; Gottfried, G. J. 1983. Picloram pellets control New Mexico locust sprouts on a cleared forest site in Arizona. Down to Earth. 39(1): 18-21. [6827] 15. DeBano, Leonard F.; Schmidt, Larry J. 1989. Improving southwestern riparian areas through watershed management. Gen. Tech. Rep. RM-182. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 33 p. 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Arizona flora. 2d ed. Berkeley, CA: University of California Press. 1085 p. [6563] 25. Knipe, O. D. 1982. Angora goats for conversion of Arizona chaparral: early results. In: Conrad, C. Eugene; Oechel, Walter C., technical coordinators. Proceedings of the symposium on dynamics and management of Mediterranean-type ecosystems; 1981 June 22-26; San Diego, CA. Gen. Tech. Rep. PSW-58. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station: 264-269. [6028] 26. 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] 27. Laurenzi, Andrew W.; Ohmart, Robert D.; Hink, Valerie C. 1983. Classification of mixed broadleaf riparian forest in Tonto National Forest. In: Moir, W. H.; Hendzel, Leonard, technical coordinators. Proceedings of the workshop on southwestern habitat types; 1983 April 6-8; Albuquerque, NM. Albuquerque, NM: U.S. Department of Agriculture, Forest Service, Southwestern Region: 72-81. [21639] 28. Layser, Earle F.; Schubert, Gilbert H. 1979. Preliminary classification for the coniferous forest and woodland series of Arizona and New Mexico. Res. Pap. RM-208. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 27 p. [1428] 29. Little, Elbert L., Jr. 1950. Southwestern trees: A guide to the native species of New Mexico and Arizona. Agriculture Handbook No. 9. Washington, DC: U.S. Department of Agriculture, Forest Service. 109 p. [20330] 30. Little, Elbert L., Jr. 1979. Checklist of United States trees (native and naturalized). Agric. Handb. 541. Washington, DC: U.S. Department of Agriculture, Forest Service. 375 p. [2952] 31. Lowe, Charles H., Jr. 1961. Biotic communities in the sub-Mogollon region of the inland Southwest. Arizona Academy of Science Journal. 2: 40-49. [20379] 32. Matheron, M. E.; Mircetich, S. M. 1985. Relative resistance of different rootstocks of English walnut to six Phytophthora spp. that cause root and crown rot in orchard trees. Plant Disease. 69(12): 1039-1041. [11544] 33. Medina, Alvin L. 1986. Riparian plant communities of the Fort Bayard watershed in southwestern New Mexico. Southwestern Naturalist. 31(3): 345-359. [1629] 34. Medina, Alvin L. 1987. Woodland communities and soils of Fort Bayard, southwestern New Mexico. Journal of the Arizona-Nevada Academy of Science. 21: 99-112. [3978] 35. Minckley, W. L.; Brown, David E. 1982. Wetlands. In: Brown, David E., ed. Biotic communities of the American Southwest--United States and Mexico. Desert Plants. 4(1-4): 223-287. [8898] 36. Minckley, W. L.; Clark, Thomas O. 1981. Vegetation of the Gila River Resource Area, eastern Arizona. Desert Plants. 3(3): 124-140. [10863] 37. Muldavin, Esteban H.; DeVelice, Robert L. 1987. A forest habitat type classification of southern Arizona and its relationship to forests of the Sierra Madre Occidental of Mexico. In: Aldon, Earl F.; Gonzales Vicente, Carlos E.; Moir, William H., technical coordinators. Strategies for classification and management of native vegetation for food production in arid zones: Proceedings; 1987 October 12-16; Tucson, AZ. Gen, Tech. Rep. RM-150. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 24-31. [2728] 38. O'Brien, G. Patrick. 1983. Power pole damage by acorn woodpeckers in southeastern Arizona. In: Davis, Jerry W.; Goodwin, Gregory A.; Ockenfeis, Richard A., technical coordinators. Snag habitat management: proceedings of the symposium; 1983 June 7-9; Flagstaff, AZ. Gen. Tech. Rep. RM-99. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 14-18. [17813] 39. Pase, Charles P.; Layser, Earle F. 1977. Classification of riparian habitat in the Southwest. In: Johnson, Roy; Jones, Dale A., technical coordinators. Importance, preservation and management of riparian habitat: A symposium; 1977 July 9; Tucson, AZ. Gen. Tech. Rep. RM-43. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 5-9. Available from: NTIS, Springfield, VA 22151; PB-274 582. [5333] 40. Pope, Dennis P.; Brock, John H.; Backhaus, Ralph A. 1990. Vegetative propagation of key southwestern woody riparian species. Desert Plants. 10(2): 91-95. [11834] 41. Powell, A. Michael. 1988. Trees & shrubs of Trans-Pecos Texas including Big Bend and Guadalupe Mountains National Parks. Big Bend National Park, TX: Big Bend Natural History Association. 536 p. [6130] 42. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843] 43. Reeves, Timothy. 1976. 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Unpublished draft on file at: U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Fire Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p. [20090] 48. Stromberg, Juliet C.; Patten, Duncan T. 1990. Seed production and seedling establishment of a southwest riparian tree, Arizona walnut (Juglans major). Great Basin Naturalist. 50(1): 47-56. [11169] 49. Stromberg, Juliet C.; Patten, Duncan T. 1990. Flower production and floral ratios of a southwestern riparian tree, Arizona walnut (Juglans major). American Midland Naturalist. 124(2): 278-288. [13780] 50. Stromberg, Juliet C.; Patten, Duncan T. 1990. Variation in seed size of a southwestern riparian tree, Arizona walnut (Juglans major). American Midland Naturalist. 124(2): 269-277. [13781] 51. Szaro, Robert C. 1980. Factors influencing bird populations in southwestern riparian forests. In: DeGraaf, Richard M., technical coordinator. 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[11573] 56. Vines, Robert A. 1960. Trees, shrubs, and woody vines of the Southwest. Austin, TX: University of Texas Press. 1104 p. [7707] 57. Quinn, Ronald D. 1990. The status of walnut forests and woodlands (Juglans californica) in southern California. In: Schoenherr, Allan A., ed. Endangered plant communities of southern California: Proceedings, 15th annual symposium; 1989 October 28; Fullerton, CA. Special Publication No. 3. Claremont, CA: Southern California Botanists: 42-54. [21319] 58. Rink, George. 1990. Juglans cinera L. Butternut. In: Burns, Russell M.; Honkala, Barbara H., technical coordinators. Silvics of North America. Vol. 2. Hardwoods. Agric. Handb. 654. Washington, DC: U.S. Department of Agriculture, Forest Service: 386-390. [16727] 59. Williams, Robert D. 1990. Juglans nigra L. black walnut. In: Burns, Russell M.; Honkala, Barbara H., technical coordinators. Silvics of North America. Vol. 2. Hardwoods. Agric. Handb. 654. 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