Date of Award:

5-2012

Document Type:

Thesis

Degree Name:

Master of Science (MS)

Department:

Plants, Soils, and Climate

Committee Chair(s)

Jennifer Reeve

Committee

Jennifer Reeve

Committee

Astrid Jacobson

Committee

Dan Drost

Abstract

In 2008–2011 a graduate project was undertaken by Davey Olsen under the supervision of Utah State University (USU) Plant, Soils and Climate professors, Drs. Jennifer Reeve, Dan Drost, and Astrid Jacobson. The project investigated a new way of measuring the benefits of applying compost to organically certified horticultural crops. In particular, the carryover of these benefits in the three years following a one-time application was studied. A field trial at the USU Organic Farm modeled the carryover of nitrogen and phosphorus in a corn and squash rotation, while laboratory analysis investigated aspects of nitrogen availability and compost decomposition over time. Results indicated that compost continued to provide benefits to crops four years after it was initially applied. It was concluded that the majority of these benefits were due to factors other than nitrogen nutrition. The ongoing benefits to crops from a single compost application are seldom accounted for by growers. The study showed that when these benefits are considered, compost use can become more economically viable. The study also considered the role that compost plays in a crop rotation, and highlighted the need for an additional nitrogen source, such as a legume cover crop, within organic crop rotations.

The results of this study have implications for compost use on organically certified farms by changing the way compost is viewed as a source of plant nutrients, as well as the time frames over which compost is regarded as being beneficial to crops. When compost carryover is considered, growers can more accurately determine the role of compost in their fertility program, and manage its use to optimize economic returns.

Checksum

57528e8277768da0f6073fc4126985ca

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .