- Compost Use in Agriculture
- On-Farm Composting
- Case Studies
- Agricultural Demos
- Compost and Mulch
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Organic Materials Management
Compost Use in Agriculture
Use of composted manures and plant materials in farming has a history almost as long as farming itself. California farmers enjoy access to a large and diverse composting infrastructure, making high-quality compost and mulch products from a variety of feedstocks available virtually everywhere in the state. California compost facilities permitted in accordance with state law and CalRecycle regulations, and inspected by our network of local enforcement agencies (LEA), meet high standards for pathogen reduction and testing of final product. Additionally, compost facilities selling to organic food producers are inspected annually by the California Department of Food and Agriculture for strict adherence to National Organic Program regulations.
Regular use of compost brings many benefits to the farmer. Some of these benefits have been studied. Other benefits are more difficult to quantify, and will vary for farmers based on frequency and amount of compost applied, soil type, crop rotations, and other factors. They include:
- Increased soil water holding capacity and reduced runoff
- Beneficial micro-organisms to improve soil health
- Addition of humus
- Addition of organic matter and carbon sequestration
- Improved soil tilth
Compost provides low levels of all primary, secondary and micronutrients. Many micronutrients become depleted from agricultural lands over time and may not be replenished with conventional fertilizers. Compiled analyses of more than 1,600 compost samples from the southwestern United States performed by Soil Control Lab found average levels of these micronutrients.
- Compost use in large-scale production of salad greens: Michael Brautovich has five watchwords when it comes to purchasing compost for Earthbound Farm, one of the nation’s largest growers of fresh salad mix and organic vegetables. “Quality, safe, consistent, mature, organic” said Brautovich, Earthbound’s senior manager for quality, food safety and organic integrity. “We are looking for compost free of chemical, physical, and biological contaminants.”
- Compost use on California rangeland: The Marin Carbon Project is performing a long-term experiment using large quantities of compost to improve forage on California rangeland. Early results suggest significant improvements in forage quality and quantity, benefits to native perennial grasses, and significant soil carbon sequestration.
- CalRecycle projects:
- Agricultural demonstrations.
- Compost Best Management Practices and Benefits. David M. Crohn, University of California Riverside. March 2011.
- Compost Demonstration Project, Placer County: Use of Compost as Primary Erosion Control Material.
A Lifecycle Model to Evaluate Carbon Sequestration Potential
and Greenhouse Gas Dynamics of Managed Grasslands,
Marcia S. DeLonge, Rebecca Ryals, and Whendee L. Silver,
University of California Berkeley, Department of
Environmental Science, Policy, and Management. Applications
of composted organic matter to grasslands can contribute to
climate change mitigation while sustaining productive lands
and reducing waste loads.
- Amending Pasture Soils Improves Forage
Quality and Economic Return: An Organic Dairy Case Study
(PDF, 468 KB), C.A. Daley, Ph.D., California State
University, Chico, College of Agriculture, Organic Dairy Program. A
long-term soil remediation field trial to study the effect
of a basic soil amendment program on forage quality and
yield, with an emphasis on the economic return that would
result from added milk production.
- Analysis of Compost Treatments to Establish Shrubs and Improve Water Quality, Brent G.Hallock, Anne Power, Steve Rein, Michael Curto, Misty Scharff, Califorinia Polytechnic State University an experiment to determine whether there is a noticeable difference in erosion control and seedling germination performance between several common types of compost applied at varying rates and methods over two subsoils.
- Basis for the Control of Soilborne Plant Pathogens With Composts, Harry A. J. Hoitink. Control of diseases through composting includes kill of plant pathogens present in wastes during and after the high-temperature process. Specific physical, chemical and biological properties of composts may have a major effect on their suppressiveness.
- Changes in Soil Properties and Carbon Content Following Compost Application: Results of On-farm Sampling (PDF, 351 KB), Sally Brown and Matt Cotton, Compost Science and Utilization (2011). Benefits associated with compost use in agricultural soils. Using a response variable to normalize across sites, improvements were seen in total carbon, reduced bulk density, increased microbial activity, total nitrogen (in comparison to control soils), water holding capacity, and water infiltration rate.
- Economic Potential of Compost Amendment as an Alternative to Irrigation in Maine Potato Production Systems, John M. Halloran, Robert P. Larkin, Sherri L. DeFauw, O. Modesto Olanya, Zhongqi He, U.S. Department of Agriculture: National Agricultural Library. This investigation demonstrates that compost is a potentially viable substitute to irrigation for potato in the northeastern U.S. however, such potential is highly dependent on suitable compost sources and application costs.
- Quantifying Benefits Associated with Land Application of Organic Residuals in Washington State. (PDF, 2.1 MB), Sally Brown, Kate Kurtz, Andy Bary, and Craig Cogger, Environmental Science & Technology. This study was conducted to quantify soil carbon storage, nitrogen concentration, available phosphorus, and water holding capacity across a range of sites in Washington State.
- Where to Buy Compost in California
- Other Tools
- Alternative Farming Systems Information Center: Specializes in library services related to aspects of alternative agriculture, such as sustainable crop and livestock farming systems, ecological pest management, and organic production, certification, and marketing.
- BioCycle article: Applying Compost in Mainstream Agriculture, Ralph Jurgens.
- California Heartland
- CalRecycle Composting Regulations
- CalRecycle's Farm and Ranch Cleanup Grants
- Leafy Greens Marketing Agreement: Industry standards for farmers growing salad greens who use manures, composts and other fertilizers.
- Planting Seeds: Food and Farming News from CDFA
- University of California Agriculture Website
- U.S. Department of Agriculture: Natural Resources Conservation Service Website
- U.S. Food and Drug Administration (FDA) Produce Safety Proposed Rule: Questions and answers on the proposed rule for produce safety. This rule is one of five proposed rules that would be foundational in the food safety system mandated by the FDA Food Safety Modernization Act.
- Woods End Laboratories
Organic Materials Management http://www.calrecycle.ca.gov/Organics/