Scientists, growers assess trade-offs in use of tillage, cover crops and compost
AuthorsLouise E Jackson
Steven A Fennimore
Steven T Koike
Diane M Henderson
William E Chaney
Karen M Klonsky
Authors AffiliationsL.E. Jackson is Professor/Specialist and Postgraduate Researcher, Department of Vegetable Crops, UC Davis; I. Ramirez is Professor/Specialist and Postgraduate Researcher, Department of Vegetable Crops, UC Davis; R. Yokota is Ranch Manager, Tanimura and Antle, Inc., Salinas; S. A. Fennimore is Weed Specialist, Department of Vegetable Crops, UC Davis; S. T. Koike is Farm Advisor and Staff Research Associate, UC Cooperative Extension, Salinas, CA; D.M. Henderson is Farm Advisor and Staff Research Associate, UC Cooperative Extension, Salinas, CA; W.E. Chaney is Farm Advisor, UC Cooperative Extension, Monterey County; K. M. Klonsky is Farm Management Specialist, Department of Agricultural and Resource Economics, UC Davis.
Hilgardia 57(2):48-54. DOI:10.3733/ca.v057n02p48. April 2003.
Use of cover crops and compost increased soil quality in irrigated, intensive production of lettuce and broccoli in the Salinas Valley. These methods had the beneficial impacts of increasing soil microbial biomass, increasing total soil carbon and nitrogen, reducing surface bulk density and decreasing the potential for groundwater pollution as a result of nitrate leaching below the root zone. These soil benefits did not lead to lower yields and occasionally resulted in fewer weeds and lower lettuce corky root disease. Although surface minimum tillage reduced yields, it led to reduced potential for nitrate leaching below the root zone. Use of conventional tillage, cover crops, and compost produced high vegetable yields and acceptable net economic returns over a 2-year period, but broccoli was more profitable than lettuce under this regime. Understanding the trade-offs of various costs and benefits will help growers choose management practices that optimize economic and environmental benefits.
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Also in this issue:Prevalence, Habitat Selection, and Biology of Protocalliphora (Diptera: Calliphoridae) Found in Nests of Mountain and Chestnut-backed Chickadees in California
How to manage “soil quality” key question for farmers and scientists
Letters: April-June 2003
Science briefs: April-June 2003
Looking back 60 years, California soils maintain overall chemical quality
Blue oak enhance soil quality in California oak woodlands
Incorporating straw may induce sulfide toxicity in paddy rice
Stubble height standards for Sierra Nevada meadows can be difficult to meet