Index of Species Information

SPECIES:  Pinus engelmannii


Introductory

SPECIES: Pinus engelmannii
AUTHORSHIP AND CITATION : Pavek, Diane S. 1994. Pinus engelmannii. 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 : PINENG SYNONYMS : Pinus latifolia Sarg. Pinus apacheca Lemm. [13,14,18,30,38] SCS PLANT CODE : PIEN2 COMMON NAMES : Apache pine Arizona longleaf pine pino real TAXONOMY : The currently accepted scientific name of Apache pine is Pinus engelmannii Carr. It is a member of the pine family (Pinaceae) [14,30,61,62]. In addition to the typical variety, there is one recognized variety in Mexico, P. e. var. blancoi Mart. [7,45,62]. Where their ranges overlap, interspecific hybrids occur between Apache pine, interior ponderosa pine (P. ponderosa var. scopulorum), and Arizona pine (P. p. var. arizonica) [12,43,44,49]. LIFE FORM : Tree FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


DISTRIBUTION AND OCCURRENCE

SPECIES: Pinus engelmannii
GENERAL DISTRIBUTION : Apache pine has a very limited distribution in the United States. It occurs in the Chiricahua, Huachuca, Dragoon, and Santa Rita mountains of Arizona and in one area of extreme southwestern New Mexico [13,18,34, 42,61]. The main part of its range is in Mexico. Apache pine occurs commonly in the Sierra Madre Occidental, extending southward from the United States border to Zacatecas [14,28,44,45]. ECOSYSTEMS : FRES21 Ponderosa pine FRES28 Western hardwoods FRES35 Pinyon - juniper STATES : AZ NM MEXICO BLM PHYSIOGRAPHIC REGIONS : 7 Lower Basin and Range KUCHLER PLANT ASSOCIATIONS : K019 Arizona pine forest K023 Juniper - pinyon woodland K031 Oak - juniper woodlands SAF COVER TYPES : 235 Cottonwood - willow 237 Interior ponderosa pine 239 Pinyon - juniper 240 Arizona cypress SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Apache pine primarily occurs in Madrean pine-oak and oak-pine forests and woodlands. Codominant and subdominant species that occur with Apache pine in these communities are Chihuahua pine (Pinus leiophylla var. chihuahuana), Mexican pinyon (P. cembroides), and alligator juniper (Juniperus deppeana); the understories are predominatly oak (Quercus spp.) [1,7,11,21,22,35]. The communities may extend upward into the mixed pine forests [9]. Apache pine forms open stands and is widely scattered in mixed pine forests with Arizona pine, Chihuahua pine, and southwestern white pine (P. strobiformis) [2,15,29]. Apache pine is the principal species in the Apache pine series [1,6,20,39,40]. Scattered Apache pine occur in riparian habitats. Along streamsides, Apache pine is a minor species in some stands of Chihuahua pine/pinyon ricegrass (Piptochaetium fimbriatum) habitat types and is codominant in Arizona cypress (Cupressus arizonica) types [15,39,41,48]. It is a minor species in the Arizona sycamore (Platanus wrightii) series and community types [39,56]. Apache pine is listed as a dominant or indicator species in the following publications: (1) Classification of the forest vegetation on the National Forests of Arizona and New Mexico [1] (2) Forest and woodland habitat types (plant associations) of Arizona south of the Mogollon Rim and southwestern New Mexico [6] (3) A digitized computer-compatible classification for natural and potential vegetation in the Southwest with particular reference to Arizona [11] (4) A series vegetation classification for Region 3 [39] (5) A forest habitat type classification of southern Arizona and its relationship to forests of the Sierra Madre Occidental of Mexico [40]. Species associated with Apache pine but not previously mentioned in Occurrence and Distribution include Arizona madrone (Arbutus arizonica), Apache plume (Fallugia paradoxa), western white honeysuckle (Lonicera albiflora), and slimflower scurfpea (Psoralea tenuiflora) [16,48].

MANAGEMENT CONSIDERATIONS

SPECIES: Pinus engelmannii
WOOD PRODUCTS VALUE : The limited distribution of Apache pine restricts its commercial importance [13,18,33]. The wood of Apache pine is hard and heavy [25,61]. It is sometimes harvested with associated pines for lumber and construction timbers. Apache pine is used locally for fuel [45]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Apache pine is of limited use to wildlife [18]. Birds, rodents, and other animals consume its seeds [25,32,59]. The intensity of seed predation was not described in the literature. However, Apache pine has synchronous cone crops at irregular intervals [52]; such masting may have evolved in response to heavy seed predation. Mexican spotted owls are yearlong residents of the Madrean oak-pine forests to which Apache pine belongs [23]. PALATABILITY : NO-ENTRY NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : Apache pine provides cover for wildlife [32]. VALUE FOR REHABILITATION OF DISTURBED SITES : Apache pine was planted with 37 other pine species in trials on sandhill sites in northwestern Florida. It did not survive [10]. OTHER USES AND VALUES : NO-ENTRY OTHER MANAGEMENT CONSIDERATIONS : Apache pine was evaluated for suitability as a timber tree at the Wind River Arboretum in Wyoming. Most transplanted trees died; three trees survived for 55 years. At that time, they had poor vigor, needle disease, snow and ice damage, and no reproduction [51]. Apache pine was included in a breeding program that studied pollen production at the Eddy Arboretum in California. Apache pine produced pollen from April through June over a 6-year period [17]. Equations to estimate understory production have been developed for the oak-pine forests in which Apache pine occurs [22]. In the oak-pine forests where Apache pine is an overstory tree, the removal of large nest trees for fuelwood can reduce habitat suitability for the Mexican spotted owl [23]. Apache pine is susceptible to southwestern dwarf mistletoe (Arceuthobium vaginatum ssp. cryptopodum). Control methods are discussed in the literature [27].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Pinus engelmannii
GENERAL BOTANICAL CHARACTERISTICS : Apache pine is a native, monoecious tree. Mature individuals are 50 to 82 feet (15-25 m) tall and have trunk diameters from 14 to 32 inches (35-80 cm) [13,25,30,45]. The bark on mature trees is about 1.5 inches (3.8 cm) thick [25]. The crown is open and round with few large branches [33,45]. Evergreen needles are in bundles of three or occasionally four or five and are 8 to 15 inches (20-38 cm) long [25,32,42,45]. Cones are 4 to 7 inches (10-18 cm) long and are borne in pairs or groups of four [25,42,45]. Seeds are just over 0.25 inch (0.6 cm) long with large wings up to 1 inch (2.5 cm) long [25,61]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Apache pine reproduces by seed; no information on vegetative reproduction was found in the literature. Apache pine populations in Chihuahua, Mexico, produce synchronous seed crops at irregular intervals [52]. Apache pine begins to bear cones when 28 to 30 years old [30]. Although the intervals between large seed crops are 2 to 4 years, some seeds are produced every year in parts of its range [25,30]. Cones mature in 2 years [25]. The seeds weigh only 0.002 ounces (0.05 g) and are wind dispersed [25,57]. Animals consume some seed [25], but it was not found in the literature whether animals contribute to effective dispersal and establishment of Apache pine. Information about cone and seed collection and seed germination conditions are discussed in the literature [30]. Optimal germination occurs on broken and washed mineral soil [25]. Apache pine seedlings tolerate significantly (P<0.05) lower light than found in random microsites [4]. Seedlings and saplings have long needles, about 6 inches in length (15 cm) [33], which may increase net photosynthesis under low light conditions. Apache pine seedlings produce a relatively deep taproot and little top-growth during their first few years [46]. Near the lower elevational limit of this species, Apache pine seedlings occur in relatively moist microsites. Just below the lowest elevational limit, Apache pine seedlings die from water stress [4]. Juveniles and saplings that have trunk diameters less than 2 inches (5 cm) at the base and are less than 3.2 feet (1 m) tall have less effective root systems for withstanding drought than mature trees [5,62]. SITE CHARACTERISTICS : Apache pine grows in climates that range from semiarid with bimodal precipitation to temperate-subhumid with most precipitation falling in summer [5,60]. Apache pine grows on dry to moderately moist canyon slopes, ridges, mesas, lower slopes, valleys, and streamside terraces [6,15,39,43, 45,54]. Apache pine ranges from 5,000 to 9,100 feet (1,524-2,750 m) in elevation [5,16,18,37,43,45,60]. Apache pine occurs on soils of varying depths and textures. Soils can be 4 to 6 inches (10-15 cm) deep with textures ranging from sandy to clayey sand with gravel [5,25,60]. Parent material can be igneous, rhyolite, basalt, or schist [7,60]. SUCCESSIONAL STATUS : Facultative Seral Species Apache pine is shade tolerant during establishment [4,25]. It becomes shade intolerant after about 6 years [25]. The successional status of Apache pine depends on location and associated species. It may be seral to or climax with any of the conifer species in mixed pine forests [15]. Apache pine is a climax species in the Madrean pine-oak woodlands and forests [6]. SEASONAL DEVELOPMENT : Needles remain on Apache pine for 2 years. Seed production requires 2 years [25]. Pollination occurs mainly during May [30,50]. Cones mature from November to December of the second year [30,45]. Seeds disperse from November to February [30,50].

FIRE ECOLOGY

SPECIES: Pinus engelmannii
FIRE ECOLOGY OR ADAPTATIONS : Mature Apache pine endure most fires and become dominant when fire susceptible species are eliminated [7,37]. Apache pine grows in oak-pine woodlands; these are probably fire-tolerant, fire-maintained communities, although the fire regime is not well understood for these associations [54]. Apache pine occurs in the Madrean oak-pine forest and adjacent conifer gallery forest in Rhyolite Canyon in the Chiricahua National Monument, Arizona. Historically, surface fires occurred episodically every 1 to 38 years [55]. Based on the fire-scars of Apache pine, the mean fire interval from 1655 to 1924 was 12.5 years in the lower canyon area [54]. Fire intervals increased with livestock grazing and the subsequent reduction in surface fuels [55]. Fire is characteristic of interior ponderosa pine forests. Fires from these communities may extend downward into mixed pine or oak-pine forests in which Apache pine occurs. In the Rincon Mountains close to the northern latitudinal limits of Apache pine, the estimated mean fire intervals from 1757 to 1983 for Arizona pine communities ranged from 1 to 13 years [3]. POSTFIRE REGENERATION STRATEGY : Tree without adventitious-bud root crown Crown residual colonizer (on-site, initial community) Secondary colonizer - off-site seed

FIRE EFFECTS

SPECIES: Pinus engelmannii
IMMEDIATE FIRE EFFECT ON PLANT : Fire effects on Apache pine are probably influenced most by tree size and fire intensity. Apache pine seedlings and saplings are probably killed by fire. With thicker bark and deeper roots, mature trees are fire resistant [7]. Once shed, the small seeds with large wings are probably killed by fire unless they are covered with an insulating layer of soil. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : The response of Apache pine to fire was not described in the literature. Since regeneration of Apache pine is exclusively through seed, rates of regeneration are probably dependent on survival of mature trees within the burn and the proximity of seed trees. Seeds will germinate in mineral soil exposed by fire as long as adequate moisture is present. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Increased grazing coupled with fire suppression has resulted in crowded, stunted Apache pine with high amounts of litter and dead fuel in the oak-pine communities [36]. This increases the fire hazard in these communities. Fire is the primary control for southwestern dwarf mistletoe infection. Prescribed understory burning has been used in interior ponderosa pine forests to control this pathogen [26]. Since Apache pine and interior ponderosa pine respond similarly to southwestern dwarf mistletoe infection [27], fire may be useful for controlling mistletoe in Apache pine.

REFERENCES

SPECIES: Pinus engelmannii
REFERENCES : 1. 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] 2. Arno, Stephen F.; Hammerly, Ramona P. 1984. Timberline: Mountain and arctic forest frontiers. Seattle, WA: The Mountaineers. 304 p. [339] 3. Baisan, Christopher H.; Swetnam, Thomas W. 1990. Fire history on a desert mountain range: Rincon Mountain Wilderness, Arizona, U.S.A. Canadian Journal of Forest Research. 20: 1559-1569. [14986] 4. Barton, Andrew M. 1992. Factors controlling lower elevational limits of plants: responses of pines to drought in the Chiricahua Mountains, Arizona. In: Ffolliott, Peter F.; Gottfried, Gerald J.; Bennett, Duane A.; [and others], technical coordinators. Ecology and management of oak and associated woodlands: perspectives in the sw United States & n Mexico: Proceedings; 1992 April 27-30; Sierra Vista, AZ. Gen. Tech. Rep. RM-218. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 191-194. [19764] 5. Barton, Andrew M.; Teeri, James A. 1993. The ecology of elevational positions in plants: drought resistance in five montane pine species in southwestern Arizona. American Journal of Botany. 80(1): 15-25. [20527] 6. 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] 7. Bennett, Peter S.; Kunzmann, Michael R. 1992. The applicability of generalized fire prescriptions to burning of Madrean evergreen forest and woodland. Journal of the Arizona-Nevada Academy of Science. 24-25: 79-84. [18324] 8. 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] 9. Bowers, Janice E.; McLaughlin, Steven P. 1987. Flora and vegetation of the Rincon Mountains, Pima County, Arizona. Desert Plants. 8(2): 50-94. [495] 10. Brendemuehl, R. H. 1981. Options for management of sandhill forest land. Southern Journal of Applied Forestry. 5: 216-222. [9305] 11. Brown, David E.; Lowe, Charles H. 1974. A digitized computer-compatible classification for natural and potential vegetation in the Southwest with particular reference to Arizona. Journal of the Arizona Academy of Science. 9: 3-11. [20374] 12. Conkle, M. Thompson; Critchfield, William B. 1988. Genetic variation and hybridization of ponderosa pine. In: Baumgartner, David M.; Lotan, James E., compilers. Ponderosa pine: The species and its management: Symposium proceedings; 1987 September 29 - October 1; Spokane, WA. Pullman, WA: Washington State University, Cooperative Extension: 27-43. [9399] 13. Correll, Donovan S.; Johnston, Marshall C. 1970. Manual of the vascular plants of Texas. Renner, TX: Texas Research Foundation. 1881 p. [4003] 14. Critchfield, William B.; Little, Elbert L., Jr. 1966. Geographic distribution of the pines of the world. Misc. Publ. 991. Washington, DC: U.S. Department of Agriculture, Forest Service. 97 p. [20314] 15. DeVelice, Robert L.; Ludwig, John A. 1983. Forest habitat types south of the Mogollon Rim, Arizona and New Mexico. Final Report. Cooperative Agreement No. 28-K2-240 between U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station and New Mexico State University. Las Cruces, NM: New Mexico State University. 47 p. [780] 16. Diem, Kenneth L.; Zeveloff, Samuel I. 1980. Ponderosa pine bird communities. In: DeGraaf, Richard M., technical coordinator. Management of western forests and grasslands for nongame birds: Workshop proceedings; 1980 February 11-14; Salt Lake City, UT. Gen. Tech. Rep. INT-86. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station: 170-197. [17905] 17. Duffield, J. W. 1953. Pine pollen collection dates--annual and geographic variation. For. Res. Notes No. 85. Berkeley, CA: U.S. Department of Agriculture, Forest Service, California Forest and Range Experiment Station. 9 p. [17970] 18. Elias, Thomas S. 1980. The complete trees of North America: field guide and natural history. New York: Times Mirror Magazines, Inc. 948 p. [21987] 19. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905] 20. Ferguson, Dennis E.; Carlson, Clinton E. 1991. Natural regeneration of interior Douglas-fir in the northern Rocky Mountains. In: Baumgartner, David M.; Lotan, James E., compilers. Interior Douglas-fir: The species and its management: Symposium proceedings; 1991 February 27 - March 1; Spokane, WA. Pullman, WA: Washington State University, Department of Natural Resource Sciences, Cooperative Extension: 239-246. [18298] 21. Floyd, Mary Elizabeth. 1981. The reproductive biology of two species of pinyon pine in the southwestern United States. Boulder, CO: University of Colorado. 269 p. Ph.D. dissertation. [1676] 22. Gallina, Sonia; Ffolliott, Peter F. 1983. Overstory-understory relationships: oak-pine forests of Sierra Madre Occidental, Mexico. In: Bartlett, E. T.; Betters, David R., eds. Overstory-understory relationships in western forests. Western Regional Res. Publ. No. 1. Fort Collins, CO: Colorado State University Experiment Station: 19-20. [3312] 23. Ganey, Joseph L.; Duncan, Russell B.; Block, William M. 1992. Use of oak and associated woodlands by Mexican spotted owls in Arizona. In: Ffolliott, Peter F.; Gottfried, Gerald J.; Bennett, Duane A.; [and others], technical coordinators. Ecology and managememt of oaks and associated woodlands: perspectives in the sw United States & n Mexico: Proceedings; 1992 April 27-30; Sierra Vista, AZ. Gen. Tech. Rep. RM-218. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 125-128. [19751] 24. 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] 25. Graves, Henry S. 1917. The pine trees of the Rocky Mountain region. Bulletin No. 460. Washington, DC: U.S. Department of Agriculture, Forest Service. 48 p. [20321] 26. Harrington, Michael G.; Hawksworth, Frank G. 1990. Interactions of fire and dwarf mistletoe on mortality of Southwestern ponderosa pine. 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: 234-240. [11296] 27. Hawksworth, Frank G.; Shaw, Charles G., III; Tkacz, Borys. 1989. Damage and control of diseases of Southwest ponderosa pine. In: Tecle, Aregai; Covington, W. Wallace; Hamre, R. H., technical coordinators. Multiresource management of ponderosa pine forests: Proceedings of the symposium; 1989 November 14-16; Flagstaff, AZ. Gen. Tech. Rep. RM-185. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 116-129. [11311] 28. Hernandez C., Victor Manuel; Hernandez, Francisco Javier; Gonzales, Santiago Solis. 1992. Ecology of oak woodlands in the Sierra Madre Occidental of Mexico. In: Ffolliott, Peter F.; Gottfried, Gerald J.; Bennett, Duane A.; [and others], technical coordinators. Ecology and management of oak and associated woodlands: perspectives in the sw United States & n Mexico: Proceedings; 1992 April 27-30; Sierra Vista, AZ. Gen. Tech. Rep. RM-218. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 39-40. [19739] 29. Jones, John R. 1974. Silviculture of southwestern mixed conifers and aspen: The status of our knowledge. Res. Pap. RM-122. Fort Collins, CO: U.S. Department of Agricutlure, Forest Service, Rocky Mountain Forest and Range Experiment Station. 44 p. [16081] 30. Krugman, Stanley L.; Jenkinson, James L. 1974. Pinaceae--pine family. 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: 598-637. [1380] 31. 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] 32. Lamb, S. H. 1971. Woody plants of New Mexico and their value to wildlife. Bull. 14. Albuquerque, NM: New Mexico Department of Game and Fish. 80 p. [9818] 33. 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] 34. Little, Elbert L., Jr. 1975. Rare and local conifers in the United States. Conservation Research Rep. No. 19. Washington, DC: U.S. Department of Agriculture, Forest Service. 25 p. [15691] 35. 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] 36. Marshall, Joe T., Jr. 1963. Fire and birds in the mountains of southern Arizona. In: Proceedings, 2nd annual Tall Timbers fire ecology conference; 1963 March 14-15; Tallahassee, FL. Tallahassee, FL: Tall Timbers Research Station: 135-141. [18998] 37. McPherson, Guy R. 1992. Ecology of oak woodlands in Arizona. In: Ffolliott, Peter F.; Gottfried, Gerald J.; Bennett, Duane A.; [and others], technical coordinators. Ecology and management of oak and associated woodlands: perspectives in the sw United States & n Mexico: Proceedings; 1992 April 27-30; Sierra Vista, AZ. Gen. Tech. Rep. RM-218. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 24-33. [19737] 38. Mirov, N. T. 1961. Composition of gum turpentines of pines. Tech. Bull. No. 1239. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 158 p. [22164] 39. Moir, W. H. 1983. A series vegetation classification for Region 3. In: Moir, W. H.; Hendzel, Leonard, tech. coords. 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: 91-95. [1672] 40. 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] 41. Parker, Albert J. 1980. Site preferences and community characteristics of Cupressus arizonica Greene (Cupressaceae) in southeastern Arizona. Southwestern Naturalist. 25(1): 9-22. [20418] 42. Peattie, D. C. 1953. A natural history of western trees. Boston, MA: Houghton Mifflin Co. 751 p. [19269] 43. Peloquin, R. L. 1971. Variation and hybridization patterns in Pinus ponderosa and Pinus engelmannii. Santa Barbara, CA: University of California at Santa Barbara. 196 p. Dissertation. [20319] 44. Peloquin, R. L. 1984. The identification of three-species hybrids in the ponderosa pine complex. Southwestern Naturalist. 29(1): 115-122. [20320] 45. Perry, Jesse P., Jr. 1991. The pines of Mexico and Central America. Portland, OR: Timber Press. 231 p. [20328] 46. Preston, Richard J., Jr. 1948. North American trees. Ames, IA: The Iowa State College Press. 371 p. [1913] 47. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843] 48. Reeves, Timothy. 1976. Vegetation and flora of Chiricahua National Monument, Cochise County, Arizona. Tempe, AZ: Arizona State University. 180 p. Thesis. [20385] 49. Rehfeldt, Gerald E. 1993. Genetic variation in the Ponderosae of the Southwest. American Journal of Botany. 80(3): 330-343. [20877] 50. Schopmeyer, C. S., tech. coord. 1974. Seeds of woody plants in the United States. Agriculture Handbook No. 450. Washington, DC: U.S. Department of Agriculture, Forest Service. 883 p. [2088] 51. Silen, Roy R.; Olson, Donald L. 1992. A pioneer exotic tree search for the Douglas-fir region. Gen. Tech. Rep. PNW-GTR-298. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 44 p. [21668] 52. Silvertown, Jonathan W. 1980. The evolutionary ecology of mast seeding in trees. Biological Journal of the Linnean Society. 14: 235-250. [10729] 53. Stickney, Peter F. 1989. Seral origin of species originating in northern Rocky Mountain forests. 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] 54. Swetnam, Thomas W.; Baisan, Christopher H.; Brown, Peter M.; Caprio, Anthony C. 1989. Fire history of Rhyolite Canyon, Chiricahua National Monument. Tech. Rep. No. 32. Tucson, AZ: University of Arizona, School of Renewable Natural Resources, Cooperative National Park Resources Studies Unit. 47 p. [10573] 55. Swetnam, Thomas W.; Baisan, Christopher H.; Caprio, Anthony C.; Brown, Peter M. 1992. Fire history in a Mexian oak-pine woodland and adjacent montane conifer gallery forest in southeastern Arizona. In: Ffolliott, Peter F.; Gottfried, Gerald J.; Bennett, Duane A.; [and others], technical coordinators. Ecology and management of oak and associated woodlands: perspectives in the sw United States & n Mexico: Proceedings; 1992 April 27-30; Sierra Vista, AZ. Gen. Tech. Rep. RM-218. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 165-173. [19759] 56. Szaro, Robert C. 1989. Riparian forest and scrubland community types of Arizona and New Mexico. Desert Plants. 9(3-4): 70-138. [604] 57. Tomback, Diana F.; Linhart, Yan B. 1990. The evolution of bird-dispersed pines. Evolutionary Ecology. 4: 185-219. [17534] 58. 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] 59. 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] 60. Villa-Salas, Avelino B.; Manon-Garibay, A. Cecilia. 1980. Multiresource management research in northern Sonora. In: IUFRO/MAB conference: research on multiple use of forest resources: Proceedings; 1980 May 18-23; Flagstaff, AZ. Gen. Tech. Rep. WO-25. Washington, DC: U.S. Department of Agriculture, Forest Service: 20-25. [15925] 61. Vines, Robert A. 1960. Trees, shrubs, and woody vines of the Southwest. Austin, TX: University of Texas Press. 1104 p. [7707] 62. Yeaton, Richard I.; Yeaton, Robin, W.; Waggoner, John P., III. 1983. Changes in morphological characteristics of Pinus engelmannii over an elevational gradient in Durango, Mexico. Madrono. 30(3): 168-175. [22560]


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