Research Plant Ecologist
Principal Research Scientist
Phone: (530) 759-1705
Pacific Southwest Research Station
Sierra Nevada Research Center
1731 Research Park Dr.
Davis, CA 95618
Ph: (530) 759-1700
Fx: (530) 747-0241
B.A. English, 1979, Vassar College, Poughkeepsie, NY
M.F.S. Forest Ecology, 1988, Yale University, New Haven, CT
Ph.D. Forest Ecosystem Analysis, 1993, University of Washington, Seattle, WA
My research has focused on the influence of forest structure, pattern and composition on ecosystem function and wildlife habitat. I've worked on identifying the particular structural features associated with spotted owl foraging and nesting, and the abundance of truffles, the main food source for the owl's prey, in these stands. With this interest I've worked on methods for describing and quantifying forest canopy structure, and how this structure varies in forest stands at different successional stages.
My current research is focused on the effects of disturbance on the structure, composition and function of Sierra Nevada mixed-conifer ecosystems. Mixed-conifer and ponderosa pines forests have been seriously impacted by a century of fire suppression and selective logging. In many areas this has reduced the number of large, old trees and increase stem densities, particularly of shade-tolerant species such as white fir and incense cedar. Fire and in some cases thinning, will be needed to restore historic forest conditions, however, the effect of these two restoration methods on ecosystem structure and function has not been systematically compared. Disturbance alters a forest's scaffold initiating changes in vegetation pattern, composition, microclimate and edaphic conditions. These in turn affect fundamental ecosystem processes (respiration, decomposition, nutrient cycling), trophic structure (invertebrate and fungal based food chains) and wildlife habitat. While many of these processes are difficult to measure, they are often strongly linked to forest structure and composition. Establishing the linkage between ecosystem function and stand structure can provide forest managers with a surrogate measure of the impacts of their activities on ecosystem health.
North, M., J. Chen, B. Song, M. Rudnicki, and B. Oakley. In review. Forest stand structure and pattern of old-growth Douglas-fir and mixed-conifer forests. Forest Science.
North, M, B. Oakley, J. Fiegener, M. Barbour, and A. Gray. In review. Influence of canopy cover and soil moisture on mixed-conifer understory community. Journal of Vegetation Science.
North, M and B. Oakley. In review. Pattern, scale and plot replication in heterogeneous forests. Journal of Vegetation Science.
Oakley, B., M. North, B. Hedlund, J. Staley and J. Franklin. In review. The effects of fire on soil nitrogen and Frankia associated with patches of the actinorhizal shrub Ceanothus cordulatus. Plant and Soil Biology.
M. North, B. Oakley, J. Chen, H. Erickson, A. Gray, A. Izzo, D. Johnson, S. Ma, J. Marra, M. Meyer, K. Purcell, B. Roath, T. Rambo, D. Rizzo, T. Schowalter. In press. Vegetation and ecological characteristics of mixed-conifer and red fir forests at the Teakettle Experimental Forest. USFS General Technical Report, PSW-GTR-183.
North, M. 2001. Ecological zone of influence: Terrestrial considerations. Pages 48-56 in Defining Ecological Zones of Influence to Giant Sequoia Ecology from Proposed Management Activities on the Sequoia National Forest. USDA Forest Service Sequoia National Forest Report.
North, M., G. Steger, R. Denton, G. Eberlein, T. Munton, and K. Johnson. 2000. Association of weather and nest-site structure with reproductive success in California spotted owls. Journal of wildlife Management 64: 797-807.
Lyons, B., N. Nadkarni and M. North. 2000. Spatial distribution and succession of Tsuga heterophylla (western hemlock) in old-growth Douglas-fir forest. Canadian Journal of Botany 78:957-968.
Lyons, B., M. North and N. Nadkarni. 1999. The distribution of epiphytes on western hemlock trees in an old-growth temperate forest. What's Up? 5(3): 4-5.
North, M., J. Franklin, A. Carey, E. Forsman and T. Hamer. 1999. Forest structure of the northern spotted owl's foraging habitat. Forest Science 45:520-527.
Van Pelt, B. and M. North. 1999. Testing a ground-based canopy model using the Wind River Canopy Crane. Selbyana 20: 357-362.
North, M.P. and J. Greenburg. 1998. Stand conditions associated with truffle abundance in western hemlock/Douglas-fir forests. Forest Ecology and Management 112:55-66.
North, M.P., J. Trappe, and J. Franklin. 1997. Standing crop and animal consumption of fungal sporocarps in Pacific Northwest forests. Ecology 78: 1543-1554.
North, M.P. and J. Reynolds. 1996. Microhabitat analysis using radio telemetry locations and polytomous logistic regression. Journal of wildlife Management 60(3): 639-528.
North, M.P., J. Chen, G. Smith, and L. Krakowiak. 1996. Initial response of understory plant diversity and overstory tree diameter growth to a green tree retention harvest. Northwest Science 70(1): 24-35.
Van Pelt, B. and M. P. North. 1996. Measuring canopy structure in Pacific Northwest old-growth forests using a stand-level crown model. Northwest Science 70 (special issue): 15-30.
North, M.P. 1995. Virgin forests and endangered species: The northern spotted owl and the Mt. Graham red squirrel. Encyclopedia of Environmental Biology. Invited chapter. Academic Press. San Diego, CA., pp. 447-461.
North, M.P. and J.M. Trappe. 1994. Small mammal exclosures for studies of hypogeous fungi. Mycologia 86:583-585.
North, M.P. and J.F. Franklin. 1992. Stand structure of multi-age spotted owl habitat. The Northwest Environmental Journal 8: 229-230.
North, M.P. and J.F. Franklin. 1990. Post-disturbance legacies that enhance biological diversity in a Pacific Northwest old-growth forest. The Northwest Environmental Journal 6: 427-429.
North, M.P. 1990. Old-growth research areas of the Department of Natural Resources. Washington State Dept. of Natural Resources Publication 256, 59pp.