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Abstract: Alfalfa is California''s single largest agricultural water user due to its large acreage and long growing season, using 490,000 to 677,000ha-m of water each year. Because of the high water usage, interest exists in midsummer deficit irrigation (no irrigation in July, August, and September) of alfalfa to provide water for transfer from water-rich areas such as the Sacramento Valley to water-short areas such as the San Joaquin Valley and southern California with the amount of transferred water equal to the difference in the evapotranspiration (ET) between fully irrigated and deficit irrigated alfalfa. This project investigated the effect of deficit irrigation of alfalfa on yield and ET. Yield and evapotranspiration were measured in fully and deficit irrigated areas of commercial alfalfa fields using the eddy covariance energy balance method in the fully irrigated part and the surface renewal energy balance method in the deficit irrigated part. Alfalfa yield, applied water, canopy coverage and plant height were measured in both areas of the field. Deficit irrigation in July and August reduced alfalfa yields by 4.68–6.47Mgha−1. Seasonal ET ranged from 1249 to 1381mm. Differences in ET between fully irrigated and deficit irrigated alfalfa ranged from 224 to 239mm. Yields of the deficit irrigated area recovered during the subsequent crop. [Copyright &y& Elsevier]

Agronomic crops, including grains, forages, and fiber, are central to California agriculture, yet face many challenges. To ensure resilience, a statewide survey was conducted by the University of California Cooperative Extension service (UCCE) to identify high-priority needs and inform extension programming based on grower, consultant, and allied industry input. The goal was to compare the importance of different topics with the level of satisfaction regarding UCCE's delivery of information on these topics. Survey respondents identified integrated pest management, nutrient and irrigation management, and variety testing as high-priority needs, with overall high satisfaction regarding UCCE's program delivery on these topics. Topics needing more focus (high priority but below-average level of satisfaction) included testing new products, soil health management, and water conservation and storage. Areas of low priority and low satisfaction included niche marketing, emerging crops, organic production, harvest/ post-harvest technology, salinity management, compost and manure management, and greenhouse gas emission reductions. To address stakeholder challenges, results from this study suggest that research and extension efforts should prioritize issues directly impacting on-farm crop production. At the same time, areas of low interest reflect a need for more support to engage farmers on these topics, particularly those concerning state environmental regulations and challenges to local and global food production and security. [ABSTRACT FROM AUTHOR]

Ethanol use in California is expected to rise to 1.62 billion gallons per year in 2012, more than 90% of which will be trucked or shipped into the state. Switchgrass, a nonnative grass common in other states, has been identified as a possible high-yielding biomass crop for the production of cellulosic ethanol. The productivity of the two main ecotypes of switchgrass, lowland and upland, was evaluated under irrigated conditions across four diverse California ecozones - from Tulelake in the cool north to warm Imperial Valley in the south. In the first full year of production, the lowland varieties yielded up to 17 tons per acre of biomass, roughly double the biomass yields of California rice or maize. The yield response to nitrogen fertilization was statistically insignificant in the first year of production, except for in the Central Valley plots that were harvested twice a year. The biomass yields in our study indicate that switchgrass is a promising biofuel crop for California. [ABSTRACT FROM AUTHOR]

Ethanol use in California is expected to rise to 1.62 billion gallons per year in 2012, more than 90% of which will be trucked or shipped into the state. Switchgrass, a nonnative grass common in other states, has been identified as a possible high-yielding biomass crop for the production of cellulosic ethanol. The productivity of the two main ecotypes of switchgrass, lowland and upland, was evaluated under irrigated conditions across four diverse California ecozones - from Tulelake in the cool north to warm Imperial Valley in the south. In the first full year of production, the lowland varieties yielded up to 17 tons per acre of biomass, roughly double the biomass yields of California rice or maize. The yield response to nitrogen fertilization was statistically insignificant in the first year of production, except for in the Central Valley plots that were harvested twice a year. The biomass yields in our study indicate that switchgrass is a promising biofuel crop for California. [ABSTRACT FROM AUTHOR]