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James Ayars
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Agricultural Engineer



 James E. Ayars



BS -  Agricultural Engineering, 1965,

        Cornell University, Ithaca, NY

MS -  Agricultural Engineering, 1973,

        Colorado State University, Fort Collins, CO

Certificate of Advanced Engineering Study, 1989,    

         Cornell University, Ithaca, NY

PhD - Agricultural Engineering, 1976,

         Colorado State University, Fort Collins, CO


Contact Information:


9611 South Riverbend Avenue
Parlier, California 93648-9757

(559) 596-2875




Current Research:

As the world population increases, the demand for a clean and adequate water supply increases as does the demand for food. Meeting the world food supply demand will require an increased reliance on irrigation. However, irrigation as the principal user of the existing water supply will have to relinquish a portion to meet the municipal, industrial and environmental needs. As a result irrigation will be required to do more with poor quality water and reduced water supply while reducing its environmental impact.


My research has focused the integrated management of irrigation and drainage systems. I have researched the use of degraded quality water for irrigation and managing the shallow ground water to improve in-situ use by crops. Column lysimeters are being used to determine the effect of water table depth and quality on in-situ use of crops. Drainage water disposal has significant negative environmental impacts and my research has evaluated management of drainage systems and alternative designs to minimize those impacts. Best management practices (BMP's) have been developed for the design and management of drainage systems. I am using weighing lysimeters to determine the crop water requirements for a wide range of crops to improve irrigation efficiency and scheduling.