The Effects of Subsurface Irrigation on Current and Subsequent Year's Growth in Shadscale

Abstract

Sursurface irrigation of individual Atriplex confertifolia (shadscale) plants was implemented in the field during the summer of 1976 through the use of vertical access tubes to a depth of 50 cm. Shoots were marked on control and watered plants and examined periodically by enumerating every leaf, bud, flower, fruit, and second-order stem. Plant response to subsurface irrigation as determined in the fall enumeration revealed a modest increase in stem length and leaf weight and summer production of lateral branches. The carryover effect of summer irrigation was reflected in new growth on shoots of watered plants in spring 1977 being more than twice the production of shoots on controls. The 1976 response to subsurface irrigation is thought to be carbohydrate storage and/or root development. Watering did not enhance bud or shoot survival overwinter.