R. Ford Denison,
Professor Emeritus, UC DavisR. Ford Denison
From 1993 through 2002, R. FORD DENISON taught crop ecology and conducted research at the University of California, Davis, on topics ranging from agricultural sustainability to the evolution of cooperation between microbes and plants.  For most of this time, he directed "the world's youngest 100-year experiment" (LTRAS.ucdavis.edu), tracking the long-term trends that determine agricultural sustainability. His work on symbiotic nitrogen fixation, a possible alternative to nitrogen fertilizers, has led to a patent and publications in journals from Nature to Field Crops Research.  One recent paper, "Darwinian Agriculture: When Can Humans Find Solutions Beyond the Reach of Natural Selection?" points out some limitations both of agricultural biotechnology and of agriculture that mimics natural ecosystems. He has been interviewed on National Public Radio, Science Update (AAAS), and DeutschlandRadio and has been an invited speaker at international meetings and at  institutions from Japan's National Agricultural Research Center to the Scripps Institute of Oceanography. He was educated at Harvard, Evergreen, and Cornell, where he earned a Ph.D. in Crop Science, with postdoctoral and sabbatical research at UC Davis, UCLA, Queen's University (Ontario), Welsh Plant Breeding Station (Aberystwyth), and University of Minnesota. His research has been supported by NSF, USDA, and California's Agricultural Experiment Station.  This web page was last updated May 2005, when he moved to the University of Minnesota.


PLB 142. Ecology of Crop Systems (4) II. Denison. Lecture, 3 hours; discussion, 1 hour. Prerequisite: Agricultural Systems and Environment 2 or Biological Sciences 1C; Math 16A or Physics 1A, or consent of instructor. Ecological processes governing the structure and behavior of managed ecosystems. Emphasis on mechanistic and systems views of the physical environment, photosynthetic productivity, competition, adaptation, nutrient cycling, energy relations and contemporary issues such as climate change.

PBI 225.
Methods and Instrumentation for Crop and Soil Science (3) III. Denison, Hsiao, Hartz, Mitchell, Pettygrove,  Scow & van Kessel. Lecture, 1 hour; discussion, 1 hour; laboratory, 3 hours. Prerequisite: Basic knowledge of plant physiology, soil science, chemistry and physics. Theory and practice of in situ sampling and instrumentation methods for crop science and related aspects of soil science (e.g. moisture and fertility) and laboratory analysis.  Not offered every year.Bob Rousseau weather station


laser scanner for leaf area

How does evolution based on "selfish genes" maintain cooperation?  We are trying to answer this question for rhizobia, symbiotic bacteria that infect legume plants like alfalfa or soybean and (to varying extents) supply them with nitrogen.  Fixing nitrogen is costly for rhizobia, so why haven't rhizobia that supply their plant hosts with nitrogen (indirectly benefiting competing rhizobia infecting the same plant) been completely displaced by "ineffective" rhizobia?  Why are ineffective rhizobia common enough to be a problem in some soils but not others?  This research may lead to practical applications, such as legume crops that selectively enrich the soil with the most-beneficial local strains of rhizobia. This research may also be relevant to other cases where symbiosis breaks down, as in coral bleaching.  As time allows, I also hope to explore other applications of modern evolutionary theory, pursuing some of the ideas in our paper on Darwinian Agriculture.  Steve Kaffka has replaced me as Director of LTRAS, but I remain interested in scientific approaches to the problem of long-term sustainability, especially that of agriculture.  To pursue my research objectives, I have often had to develop new tools, including mechanistic computer models and noninvasive scientific instruments, such as the nodule oximeter or a laser-scanner (at right) to measure green leaf area index in the field.


Other recent grants on which I was principal investigator or co-PI include:


Nodule chambers on alfalfa


Computer Models Available to Download

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Education and Employment History

Professional Activities

New address

Ecology, Evolution and Behavior          
University of Minnesota                      
1987 Upper Buford Circle
St. Paul, MN 55108                          
E-mail:   First five letters of my last name + 036 + umn.edu (you know where to put the @)