Ventura County Resource Conservation District

In June 1998, the CIWMB (now known as the Department of Resources Recycling and Recovery or CalRecycle) contracted with the Ventura County Resource Conservation District (VCRCD) to continue and enhance its Calleguas Creek Watershed Project relative to using municipal mulch. CIWMB funding, which totaled $20,000, allowed the partnership to collect additional data on the efficacy of mulch for erosion control in citrus orchards. The data is graphically presented in a CalRecycle brochure Stop Runaway Soil--Use Mulch! highlighting the advantages and disadvantages of mulch, spreading costs, and use guidelines for erosion control in citrus orchards.


  • Collect data on mulch performance with respect to erosion control.
  • Conduct at least one field day and one workshop for growers.
  • Develop a brochure on mulch specification and use guidelines for erosion control in citrus orchards of varying topography.

Partnership Organizations

  • Fiscal Agent: Ventura County Resource Conservation District
  • Contract Manager: Peggy Rose, VCRCD
  • Key Partners: VCRCD, U.C. Cooperative Extension, Los Angeles Regional Water Quality Control Board, Coastal Conservancy, and USDA/NRCS
  • Participating Growers: Numerous Ventura County growers located in Grimes and Long Canyons

Project Components

  1. Data Collection. The partnership recorded soil erosion, weed reduction, mulch depth, air temperature, tree size, analyses of soil and leaf tissue, and conservation of irrigation water associated with different applications of mulch made primarily from green material.
  2. Coordination of Field Days and Workshops. During the course of the project, the partnership team conducted two field-days for commercial growers, one end-user workshop, and published articles on project progress and results in VCRCD newsletters, local newspapers, and scientific publications. It also conducted follow-ups with workshop attendees to determine if they use mulch or cover crops for erosion control.
  3. Reporting and Publishing Results. The partnership provided periodic project status reports and developed use guidelines for citrus growers.


  • Demonstrate the value of mulch for erosion control in citrus orchards.
  • Disseminate the results of the demonstration project to citrus growers in southern California.