Jacob lloyd weed seeds


The primary focus of my program is to conduct applied research and Extension outreach in grass and legume seed crops in Oregon.

Extension Small Farms Program

  • Soil Science Education
  • Organic & Sustainable Agriculture and Food Production.
  • Service Learning
  • Student Farming

Potato Variety Development and Other Row Crops

  • Cultural Management
  • Pest and Disease Control
  • Seed Production
  • Irrigation Efficiencies

Welcome to the Department of Crop and Soil Science

As a farmer, I appreciate the deep connection between agricultural and natural systems. I enjoy sharing these perspectives and lessons learned over the years (from my involvement in production agriculture as well as research findings) with students here in Oregon and across the globe.

Seed Science and Technology

Seed quality evaluation in relation to the physiology of seed germination, vigor, dormancy, storability, post-harvest technologies, and the relationship to field performance. Accepts only self-funded graduate students.

Lane County (also serving Benton and Linn Counties)

Extension Cereal Variety Program
Columbia Basin Agricultural Research Center
48037 Tubbs Ranch Rd.
Adams, OR 97810

Climate Change science and solutions

Focus areas: Farm and food system policy, local and regional food supply chains, community food system development.

In her work Mary creates professional development opportunities for Extension faculty and staff in the College of Agricultural Sciences that provide evidence-based approaches to instructional design, active teaching strategies, and program evaluation.

Online Course Development and Delivery, facilitating professors building courses and students taking online offerings.

Commercial agriculture Extension in Jackson and Josephine counties

The processes at the interface between organic matter and mineral surfaces, including mineral surface properties, organic matter properties, bonding mechanisms, adsorption processes, mineral-microbial interactions, and organic matter turnover dynamics.

  • Plant breeding and genetics curriculum development and distance learning
  • Quantitative genetics
  • Experimental design and statistics
  • Breeding specialty crops for niche markets in Oregon (currently oats, flax, corn and meadowfoam)

Nutrient cycling in natural and human-disturbed ecosystems, including the attenuation of increased nitrogen inputs to terrestrial ecosystems by soils and vegetation, detrital controls on soil organic matter formation.

I am not accepting new graduate students at this time.

Research/Career Interests

Taught Ecampus SOIL 511 in Winter 2019/2020 and Summer 2021 terms.

Dryland Cereal Production

Agricultural watershed monitoring & alternative dryland crops

  • Breeding multi-use naked barley for organic systems
  • Barley for culinary uses
  • Exploring seed coat color in barley

I teach large-enrollment non-major courses in Soil Science and Environmental Science for the Sustainability Double-Degree program and the Crop and Soil Science Department at Oregon State University, both on the Corvallis campus and via OSU E-campus.

Students in my classes are often busy juggling home, children, work, and school. I strive for inclusiveness and accommodation. My focus is on helping students find ways to complete their class work, amidst all the turmoil and stressors that unfold daily.

I am no longer accepting graduate students due to planned retirement in 2021.

Geochemical, hydrologic, and biogeochemical processes in the critical zone
Global carbon cycle
Ecosystem nutrient sources and cycling
Radiogenic and metal isotope tracers

My general research activities are chemistry, composition, and quality of post-harvest crops, with a focus on aroma and flavor compounds identification, chemical characterization, and analysis; and soil chemistry.

Oilseed and Fiber Crops

Responsible for research and extension programming related to cropping systems in Malheur County

Ecology and management of insect vectors of plant pathogens

  • Integrated Pest Management
  • Insects-Plant Interactions
  • Biological Control
  • Insect Ecology-Insect Movement
  • Chemical Control

Research interests include crop water use, irrigation, water and chemical movement through soil, macropore flow, water quality, and alternative crop evaluation and management in a semi-arid climate.

Fundamental and applied research of cereal grain components,

Wheat- and barley-based foods,

Fermentation as a vehicle for improving cereal-foods’ nutritional profiles.

My research focuses on Potato Breeding and Germplasm Improvement using traditional, molecular, and genomic tools. My program will aim at developing new potato cultivars with increased biotic and abiotic stress tolerance, nutrient efficiency and processing quality.

Field crops extension and applied research activities in Deschutes County

Field crop production in the South Willamette Valley


field crop production in the mid-Willamette Valley; grass seed, oilseeds, mint, hops, small grains, wheat

Extension Agronomist with field crop responsibilities in Union, Baker, and Wallowa Co.

Specialty: Forage Agronomy, Cellulosic Bioenergy, Soil and Water Conservation

Collaborative Interests:

Focused on dryland cropping systems, soil, water and nutrient management, soil erosion, soil quality, and rotational crops.

Habitat and Time Are More Important Predictors of Weed Seed Predation than Space on a Diversified Vegetable Farm in Maine, USA

Postdispersal weed seed predation is a significant source of weed mortality in agroecosystems. The magnitude of seed predation, however, is variable. Understanding the relative importance of factors driving variability in seed predation rates will increase the potential utility of seed predation to farmers. We conducted landscape-scale field experiments to quantify and compare the effects of space, time of sampling, and habitat on weed seed predation. Seed predation assays, with and without vertebrate exclosures, measured seed predation rates at spatially explicit sample sites across 8.5 ha of crop and noncrop habitats on a diversified organic vegetable farm in Maine. Total and invertebrate seed predation averaged 8% and 3% d −1 , respectively. Vertebrate seed predators detected by motion-sensing cameras included small mammals and birds. A ground beetle, Harpalus rufipes , was highly dominant in pitfall traps, comprising 66% of invertebrate seed predators captured within crop fields. Seed predation was randomly distributed in space. However, time of sampling and habitat were highly significant predictors of seed predation. Variance partitioning indicated that habitat factors explained more variation than did time of sampling. Total seed predation was greater in crop and riparian forest habitats than in mowed grass, meadow, or softwood forest. Generally, invertebrate seed predation was greatest at sites with an intermediate degree of vegetative cover, whereas habitat type was the chief biotic determinant of vertebrate seed predation rates. These results suggest cover cropping and wetland conservation as practices that may bolster seed predation rates.


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Current address: Department of Plant Sciences, University of Wyoming, Laramie, WY 82071.

Associate Editor for this paper: Adam Davis, USDA-ARS.


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