Aaron L. Heinrich
Faculty Research Assistant, Orchard Crops

From 2012 until 2017 I provided research support for several faculty members in the Horticulture and Crop and Soil Science Departments, as well a directed my own grant funded applied research program under the guidance of faculty. Although the focus of much of my work has been on nutrient management in vegetable crops, I worked on a variety of topics including disease and weed management. 

In 2017 I took a new position at the North Willamette Research and Extension Center providing support to the orchard crop extension specialist, Nik Wiman. In this position I will be working primarily with hazelnuts and cider apples.

The primary objective of my research is to provide the agricultural community with practical, science based information and technology necessary to be economically competitive and environmentally sustainable.

North Willamette Research and Extension Center
Department of Horticulture
North Willamette Research and Extension Center
15210 NE Miley Rd
Aurora, OR 97002
United States
(541) 740-5750


Vegetable crops

Nutrient Management

  • Evaluate the potential for enhanced efficiency fertilizers to reduce improve crop production by reducing nitrate leaching and ammonia volatilization losses.
  • Refine phosphorus fertilizer recommendations for sweet corn and snap beans.
  • Elucidate the effect of bean root rot on the ability of the crop to access soil phosphorus.
  • Provide organic farmerswith resources on how to manage their soil fertility program to minimize environmental losses.
  • Measure the N mineralization potential of conventionally and organically managed soils growing processed vegetables.
  • Evaluate theeconomics and performance of liming materials

Disease Management

  • Identify the most economical control strategies to control the disease, clubroot in brassicas. These include: 1) crop rotation, 2) soil pH management, and 3) growing resistant varieties.

Cover cropping

  • Utilize various cover cropping strategies to minimize nutrient and sediment loss, focusing on the seasonal floodplain.

Water Management

  • Explore the potential to reduce water use through deficit irrigation yet maintain yield and product quality
  • Explore the relationship between root diseases and irrigation for winter squash


SOIL 316: Nutrient Cycling in Agroecosystems (2013 and 2014 instructor; 2015 co-instructor with Dan Sullivan; 2016 lab instructor). This course addresses nutrient management principles and practices that are relevant to production of annual and perennial crops. Topics addressed include: nutrient forms, transformations, and cycling; diagnosis and correction of nutrient deficiencies, pH and salinity; impact of nutrient management practices on crop production, soil health, nutrient use efficiency, and environmental quality; and organic and inorganic fertilization.


M.S. Soil Science and Biogeochemistry, 2009, University of California
B.S Environmental Science, 2002, Oregon State University

Research and Professional Experience
2012 to Present. Faculty Research Assistant in Horticulture. Oregon State University.  Corvallis, OR. Develop and implement grant-funded research in the areas of nutrient, weed, and disease management. Develop strategies to disseminate research results through meetings, field days, and through the web.

2009-2012. Staff Research Associate II for Vegetable Crop and Weed Science Farm Adviser.  University of California Cooperative Extension, Monterey, CA. Design, implement, and present results (written, orally, and multimedia) from applied research projects involving vegetable crops in the laboratory, greenhouse, and in the field. Research was primarily focused on sustainable nutrient management strategies.

2006-2009. Graduate Student Researcher. University of California, Davis, CA.  Design and implement research projects in the field and laboratory to understand the nitrogen fertilizer value of solid, semi-solid, and liquid dairy manures stored under a range of aerobic and anaerobic conditions.


Peer Reviewed

2017. Heinrich, A.L., S. Kawai, and J. Myers. Screening brassica cultivars for resistance to western Oregon clubroot pathotypes. HortTechnology. 27: 510-516

2017. Sullivan, D., E. Peachey, A. Heinrich, and L. Brewer. Nutrient Management for Sustainable Vegetable Cropping Systems in Western Oregon. OSU Extension publication EM9165 https://catalog.extension.oregonstate.edu/em9165

2016. Heinrich, A.L., A. Stone, D. Sullivan., J. Myers, and E. Peachy. Integrated Clubroot Management for Brassicas. OSU Extension publication EM9148 https://catalog.extension.oregonstate.edu/em9148

2016. Heinrich, A.L., D. Sullivan, and E. Peachey. Snap bean nutrient management (western Oregon). OSU Extension publication EM9154 https://catalog.extension.oregonstate.edu/em9154

2016. Heinrich, A.L., J. Falen, and A. Stone. Soil phosphorus and potassium trends on a long term organic farm: Persephone Farm case study. eOrganic http://articles.extension.org/pages/74053.

2014. Heinrich, A.L., R. Smith, and M. Cahn. Winter cover cropping strategies to reduce nitrate leaching in intensive vegetable production systems. HortTechnology. 24:502-511

2013. Heinrich, A.L., R. Smith, and M. Cahn. Nutrient and water use of fresh market spinach. HortTechnology 23:325-333

2012. Heinrich, A.L. and G.S. Pettygrove. Influence of dissolved carbon and nitrogen on mineralization of dilute liquid dairy manure. Soil Science Society of America Journal. 76:700–709


2017. Integrated Clubroot Management Strategies for Brassica Crops. eOrganic webinar. Feb 15. http://articles.extension.org/pages/74054/integrated-clubroot-management-strategies-for-brassica-crops

2013. Conserving Wildlife on Willamette Valley Farms: Kenagy Family Farm. https://www.youtube.com/watch?v=e_HDuUCIXe4

2013. Conserving Wildlife on Willamette Valley Farms: Pearmine Farms. https://www.youtube.com/watch?v=e_HDuUCIXe4

2012. Alternative Cultivators for Organic Vegetable Production. http://www.youtube.com/watch?v=I4kzebMG6rE

2011. Low-residue Winter Cover Crops for Vegetable Production in the Salinas Valley, CA. http://www.youtube.com/watch?v=k0oVVJ_BA7s