Water Penetration of Vineyard Soils as Modified by Cultural Practices

Abstract

Extensive acreage of vineyard soils in the San Joaquin Valley appears to have poor and unstable structure which deteriorates upon contact with water. Water may cause deterioration of these aggregates in two ways: first, hydration which disperses the soil structure through swelling; and second, physical breakdown of the aggregates due to the erosive action of the moving water. The dispersed particles are carried into the upper soil pores and precipitate on the surface as a crust. Use of high electrolyte irrigation water and addition of gypsum to the soil increased the rate of water penetration. Aside from that, rate of water penetration was in direct proportion to the degree of soil crust prevention. A cover crop and organic matter added to the soils improved the rate of water penetration as long as a crust did not dominate. Penetration appeared to improve when the soil crust was disturbed by mechanical means.