Washington State University

Organic Farming Systems and Nutrient Management

 Composts and Nutrient Management  


Composting stabilizes organic wastes, reducing nutrient availability, allowing their use at high application rates as a soil amendment. Composts do affect available nutrient levels in soil, often causing short term immobilization (tie-up) of nitrogen, but a long term slow release. We have evaluated effects of compost applications on nitrogen availability and soil properties.


Compost Operators Training at WSU Puyallup: Training and certification for Compost Facility Operators, Managers, and officials involved with Composting. Hands on composting, field trips, exam.

Yard Trimmings Yard trimmings are organic materials such as lawn clippings, leaves, and pruned material that is applied, without any processing, directly to soil to be amended.

Food Waste Compost Earthtub Composting Project.

Calculating Bulk Density How to calculate bulk density of composts and compost- type materials such as manures and yard waste.

Clopyralid in Compost  Facts and background about the Clopyralid contamination problem.

Compost Mixture Calculator version 2.1 The Compost Mix Calculator is a spreadsheet that calculates compost mixture C:N ratio and moisture content, based on the analysis of your feed stocks and the mixture proportions that you choose. You can use the spreadsheet to evaluate the effects of different feedstock mixtures on C:N ratio and moisture content of the initial pile. It also calculates material bulk density and free air space.



Washington State Compost Educator's Guide (request pdf e-copy). Wescott, H., A. Bary, C. Cogger, C. Sullivan, and A Mack. Washington St. Univ. The purpose of the guide is to: provide consistent, science-based information about residential composting and vermicomposting for use in Washington State, assist compost educators in creating training events such as workshops, and inspire a clear vision for home composting as a cornerstone of sustainable living.

What does compost analysis tell you about your compost? (online pdf). Bary, A., C. Cogger and D. Sullivan.  2002.  Poster at Biologically Intensive and Organic Farming Research Conference. Yakima, WA.

Comparison of a gas detection tubes test with the traditional alkaline trap method to evaluate compost stability. (request pdf e-copy) Benito, M, A. Masaguar, A. Moliner, C.G. Cogger, and A.I. Bary. 2005. Biol. Fertil. Soils 41:447-450.

Potential compost benefits for restoration of soils disturbed by urban development. (request pdf e-copy) Cogger, C.G. 2005. Compost Sci. Utiliz. 13:243-251.

Soil and redosier dogwood response to incorporated and surface-applied compost. (request pdf e-copy) Cogger, C., R. Hummel, J. Hart, and A. Bary. 2008. Hortsci. 43:2143–2150.

Backyard composting. (online pdf) Cogger, C.G. and D.M. Sullivan. 2009. EB 1784E. Washington State University Cooperative Extension.

Como hacer y usar el compost. (pdf en español, gratis) Cogger, C.G., D.M. Sullivan, and J.A. Kropf. 2001. Oregon State University Extension Service. EC-1544-S.

Nitrogen availability seven years after a high-rate food waste compost application. (request pdf e-copy) Sullivan, D.M., A.I. Bary, T.J. Nartea, E.A. Myhre, C.G. Cogger, and S.C. Fransen. 2003. Compost Sci. Util. 11:265-275.

Food waste compost effects on fertilizer nitrogen efficiency, available nitrogen, and tall fescue yield. (request pdf e-copy) Sullivan, D.M., A.I. Bary, D.R. Thomas, S.C. Fransen, and C.G. Cogger. 2002. Soil Sci. Soc. Am. J. 66:154-161.

Fertilizer nitrogen replacement value of food residuals composted with yard trimmings, paper, or wood wastes. (request pdf e-copy) Sullivan, D.M., S.C. Fransen, A.I. Bary, and C.G. Cogger. 1998. Compost Sci. 6(1):6-18.

Slow-release nitrogen from composts: The bulking agent is more than just fluff. Sullivan, D.M., S.C. Fransen, A.I. Bary, and C.G. Cogger. 1998. p. 319-325. In: S.L. Brown, J.S. Angle, and L.W. Jacobs (ed.) Beneficial co-utilization of agricultural, municipal, and industrial by-products. Kluwer Academic Publishers, Dodrecht, The Netherlands. [book chapter]