Selected Publications

Seed systems have an important role in the distribution of high quality seed and improved varieties. The structure of seed networks also helps to determine the epidemiological risk for seedborne disease. We present a new method for evaluating the epidemiological role of nodes in seed networks, and apply it to a regional potato farmer consortium (CONPAPA) in Ecuador. We surveyed farmers to estimate the structure of networks of farmer seed tuber and ware potato transactions, and farmer information sources about pest and disease management. Then we simulated pathogen spread through seed transaction networks to identify priority nodes for disease detection. The likelihood of pathogen establishment was weighted based on the quality and/or quantity of information sources about disease management. CONPAPA staff and facilities, a market, and certain farms are priorities for disease management interventions, such as training, monitoring and variety dissemination. Advice from agrochemical store staff was common but assessed as significantly less reliable. Farmer access to information (reported number and quality of sources) was similar for both genders. Women had a smaller amount of the market share for seed-tubers and ware potato, however. Understanding seed system networks provides input for scenario analyses to evaluate potential system improvements.
Phytopathology, Special Epidemiology Issue:In press

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Seed systems analysis

Tracking the spread of diseases, varieties, and ideas in farmer seed systems

Angiosperm and sedge systematics

Studying the evolutionary history of angiosperms - particularly sedges

Invasive species risk assessments

Trying to impact policy with better information about risks related to invasive species


I have taught:

  • Plant Ecology
  • Plant lab
  • Biology lab II for non-majors
  • Evolution

If I have the chance I would like to develop courses about:

  • plant epidemiology
  • comparative phylogenetics (in R)
  • bioinformatic pipelines
  • evolution
  • forest/plant ecology
  • quantitative methods field based and in R
  • scientific collections based research
  • network analyses (borrowing from social sciences)
  • data science using R
  • citizen science
  • conservation policy analysis
  • biosecurity