Diana F. Tomback, Ph.D., Professor

Research Interests

1. Seed dispersal and ecology of five-needled white pines
2. Conservation and restoration of whitebark pine

Information on whitebark pine ecology has become particularly valuable as a consequence of major population declines in the northern Rocky Mountains of the U.S. and elsewhere throughout its range.  These losses result from a combination of past fire exclusion policies and white pine blister rust (Cronartium ribicola), a fatal fungal disease introduced from Europe to the western United States early this century.  Currently, the upsurge in mountain pine beetles (Dendroctonus ponderosae) poses an additional threat to whitebark pine.  Management strategies, based in part on our previous work, are being devised and implemented on a limited basis by a number of colleagues, such as Steve Arno (retired) and Bob Keane at the Fire Sciences Laboratory, USDA Forest Service, Rocky Mountain Research Station and Mary Francis Mahalavich, geneticist for Region I, USDA Forest Service. 

Out of concern for the future of whitebark pine, several of my colleagues and I started a 501 (c) (3) non-profit organization, the Whitebark Pine Ecosystem Foundation http://www.whitebarkfound.org/ which is dedicated to restoration of whitebark pine ecosystems and educating the public about the ecological importance of whitebark pine.  I have served as founding director of the WPEF since 2001. 

My students and I work at the plant-animal interface, studying both the behavior and ecology of the seed dispersers and the ecology and population biology of the pines that they disperse. Much of our work has focused on the coevolved mutualism between whitebark pine (Pinus albicaulis) and Clark's Nutcracker (Nucifraga columbiana). My doctoral studies documented the fundamental nutcracker-whitebark pine interaction. This led to more detailed investigations of the impact of seed dispersal by nutcrackers on the ecology and population biology of pines. Some investigations have made use of stand-replacing fires to examine patterns of forest regeneration resulting from nutcracker seed dispersal.

Examples of studies involving whitebark pine include the following:

• Effectiveness of seed dispersal by wind vs. seed dispersal by wind vs. seed dispersal by nutcrackers functional relationship between distance from seed source and density of post-fire whitebark pine regeneration; forest process model incorporating this information (with colleague Robert Keane and others) (western Montana).
• Impact of the exotic fungal disease, white pine blister rust on post-fire regeneration of whitebark pine (northern Idaho).
• Effects of delayed seed germination on patterns of post-fire whitebark pine recruitment in the Greater Yellowstone Area following the 1988 fires.
• Genetic population structure of whitebark pine in the Greater Yellowstone Area (with colleague Leo Bruederle) postfire regeneration of whitebark pine in areas with high blister rust infection levels.  

Specific examples of other research include:

• Growth form analysis of whitebark, limber and Swiss stone pine.
• Fitness comparison among growth forms in limber pine.
• Seed dispersal in a peripheral population of limber pine.
• Seed dispersal of southwestern white pine in Colorado and Arizona.

Courses Taught

• Biology 3411, Principles of Ecology
• Biology 4974/5974, Evolution
• Biology 4154/5154, Conservation Biology
• Biology 4052/5052, Advanced Ecology

Education

• Ph.D.:  University of California at Santa Barbara, Biological Sciences
• M.A.:  University of California at Los Angeles, Zoology
• B.A.:  University of California at Los Angeles, Zoology

Publications

Dr. Tomback's complete list of publications (pdf) »

1999-2007

Resler, L. M., and D. F. Tomback. 2007. Blister rust prevalence in krummholz whitebark pine: Implications for treeline dynamics. Arctic, Antarctic, and Alpine Research, in press.

McKinney, S. T., and D. F. Tomback. 2007 The influence of white pine blister rust on seed dispersal in whitebark pine. Canadian Journal of Forest Research 37:1044-1057.

Tomback, D. F. 2007 Whitebark pine: Ecological importance and future outlook. Proceedings—Whitebark Pine: A Pacific Coast Perspective, USDA Forest Service, Region 6, in press, 11 pp.

Schwandt, J.W., D.F. Tomback, R.E. Keane, W.W. McCaughey, and S. J. Holly. 2007. First Year Results of a whitebark pine seed planting trial near Baker City, OR. Proceedings—Whitebark Pine: A Pacific Coast Perspective, USDA Forest Service, Region 6, in press, 7 pp.

Tomback, D. F., A. S. Schoettle, K. E. Chevalier, and C. A. Jones. 2005. Life on the edge for limber pine: seed dispersal within a peripheral population. Écoscience 12:519-529.

Tomback, D. F. 2005. The impact of seed dispersal by Clark’s nutcracker on whitebark pine: multi-scale perspective on a high mountain mutualism. Pages 181-201in: Mountain Ecosystems: Studies in Treeline Ecology, G. Broll and B. Keplin (ed.), Springer.

Tomback, D.F., R.E. Keane, W.W. McCaughey, and C. Smith. 2004, 2005 revision. Methods for surveying and monitoring whitebark pine for blister rust damage and infection. Whitebark Pine Ecosystem Foundation, www.whitebarkfound.org . (peer reviewed)

Sniezko, R.A., D.F. Tomback, R.M. Rochefort, e. Goheen, R. Hunt, J.S. Beatty, M. Murray, and F. Betlejewski. 2004. Exotic pathogens, resistant seed and restoration of forest tree species in western North America. Pp. 21-26. In: Proceedings of the Second Conference on Klamath-Siskiyou Ecology. K. L. Mergenthaler, J.E. Williams, and E. S. Jules (eds.). Conference held May 29-31, 2003, Siskiyou Field Institute, Cave Junction, Oregon.

Tomback, D.F. 2003. The rapid decline of whitebark pine communities: ecological and biodiversity implications, pp. 31-42 In: Ecological and Earth Sciences in Mountain Areas. Proceedings of a symposium held in Banff, Sept. 6 to 10, 2002. (In recognition of 2002, U.N. Year of the Mountain.) L. Taylor, K. Martin, D. Hik, and A. Ryall (eds.). The Banff Centre for Mountain Culture, Banff, Alberta, Canada.

Samano, S., and D. F. Tomback. 2003. Cone opening phenology, seed dispersal, and seed predation in southwestern white pine (Pinus strobiformis) in southern Colorado. Écoscience 10:319-326.

Tomback, D. F., and K. C. Kendall. 2002. Rocky road in the Rockies: challenges to biodiversity. Pages 153-180 in: Rocky Mountain futures: an ecological perspective, J.S. Baron (ed). Island Press, Washington, D. C. Preface by Paul Ehrlich.

Tomback, D.F., A.J. Anderies, K.S. Carsey, M.L. Powell, and S. Mellman-Brown. 2001. Delayed seed germination in whitebark pine and regeneration patterns following the Yellowstone fires. Ecology 82:2587-2600.

Tomback, D.F., S. F. Arno, and R. E. Keane, editors. 2001. Whitebark Pine Communities: Ecology and Restoration. Island Press, Washington, D.C.

• Tomback, D.F., S. F. Arno, and R. E. Keane. The compelling case for management intervention, chapt. 1. Pages 3-25.

• Tomback, D.F. Clark’s nutcracker: agent of regeneration, chapt.5. Pages 89-104.

• McCaughey, W.W., and D.F. Tomback. The natural regeneration process, chapt. 6. Pges 105-120.

• Tomback, D.F., and K.C. Kendall. Biodiversity losses: the downward spiral, chapt. 12. Pages 243-262.

• Arno, S.F., D.F. Tomback, and R.E. Keane. Whitebark pine restoration: a model for wildland communities, chapt. 20. Pages 416-419.

Tomback, D.F. 2000. Amphibians, chapt. 8, pp. 265- 272. In: Sierra East, G. Smith (ed.). University of California Press, Berkeley.

Tomback, D.F. 2000. Reptiles, chapt. 9, pp. 273-289. In: Sierra East, G. Smith (ed.). University of California Press, Berkeley.

Tomback, D.F. 2000. Birds, chapt. 10, pp. 290-389. In: Sierra East, G. Smith (ed.). University of California Press, Berkeley.

Tomback, D.F. 2000. Mammals, chapt. 11, pp. 390-449. In: Sierra East, G. Smith (ed.). University of California Press, Berkeley.

Fledman, R., D.F. Tomback, and J. Koehler. 1999. Cost of mutualism: completion, tree morphology, and pollen cone production in limber pine clusters. Ecology 80:324-329

Selected Publications:

Tomback, D.F. 1998. Clark’s Nutcracker (Nucifraga columbiana). In The Birds of North America, No. 331 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists’ Union, Washington, DC, 24 pp.

Johnson, S.A., L.P. Bruederle, and D.F. Tomback. 1998. A mating system conundrum: hybridization in Apocynum (Apocynaceae). American Journal of Botany 85:1316-1323.

Bruederle, L.P., D.F. Tomback, K.K. Kelly, and R.C. Hardwick. 1998. Population genetic structure in a bird-dispersed pine, Pinus albicaulis Engelm. (Pinaceae). Canadian Journal of Botany 76:83-90.

Fleck, D.C., and D.F. Tomback. 1996. Tannin and protein in the diet of a food-hoarding granivore, the Western Scrub Jay. The Condor 98:474-482.

Tomback, D.F., J.K. Clary, J. Koehler, R.J. Hoff, and S.F. Arno. 1995. The effects of blister rust on post-fire regeneration of whitebark pine: the Sundance Burn of northern Idaho. Conservation Biology 9:654-664.

Carsey, K.S., and D.F. Tomback. 1994. Growth form distribution and genetic relationships in tree clusters of Pinus flexilis, a bird-dispersed pine. Oecologia 98:402-411.

Tomback, D.F., S.K. Sund, and L.A. Hoffmann. 1993. Post-fire regeneration of Pinus albicaulis: height-age relationships, age structure, and microsite characteristics. Canadian Journal of Forest Research 23:113-119.

Tomback, D.F., and Y.B. Linhart. 1990. The evolution of bird-dispersed pines. Evolutionary Ecology 4:185-219.

Linhart, Y.B., and D.F. Tomback. 1985. Seed dispersal by Clark’s nutcrackers causes multi-trunk growth form in pines. Oecologia 67:107-110.

Tomback, D.F. 1983. Nutcracker and pines: coevolution or coadaptation, pp. 170-223. In Coevolution, M.J. Nitecki (ed.), University of Chicago Press. Proceedings of the Fifth Annual Spring Systematics Symposium, Field Museum of Natural History, Chicago, Illinois.

Tomback, D.F. 1982. Dispersal of whitebark pine seeds by Clark’s Nutcracker: a mutualism hypothesis. Journal of Animal Ecology 51:451-467.

Tomback, D.F. and K.A. Kramer. 1980. Limber pine seed harvest by Clark's Nutcracker: timing and foraging behavior. Condor 82:467-468.

Tomback, D.F. 1980. How nutcrackers find their food stores. Condor 82:10-19.

Tomback, D.F. Pre-roosting flight of the Clark's Nutcracker. Auk 95:554-562.

Tomback, D.F. 1978. Foraging strategies of Clark’s Nutcracker. Living Bird 16:123-161.