Salt Tolerant Forages for the Reuse of Saline Drainage Water

Current practices for handling drainage water in the western San Joaquin Valley (WSJV) are not sustainable. The soil quality of 300,000 ha of land in the WSJV is adversely affected by the presence of shallow or perched water (0 to 1.5 m). Without a means of disposing of drainage water, increasing amounts of farmland in the WSJV will become salt impaired, and will be removed from production. Using drainage water to produce forages that are salt-tolerant would reduce the volume of drainage water and the amount of land needed for its disposal in evaporation ponds by up to an order of magnitude (Oster, 1997), thereby lowering the cost of disposal and limiting the exposure of wildlife to potentially toxic waters. High quality forages for dairy cattle, beef cattle, and sheep are in short supply in the Central Valley of California. Salt-tolerant forages may help provide improved forage supplies. Forage grasses like Bermuda grass (Cynodon dactylon (L.) Pers.) will use more water than most tree species in the same locations because of greater salt tolerance, and have an obvious use for livestock (Oster et al., 1997). However, agricultural drainage water in the WSJV often contains trace elements such as Se that can harm wildlife and livestock (Deverel and Millard, 1988; Fuji and Swain, 1995). These trace elements may adversely influence livestock performance and health and such possible effects must be monitored. If forage production using drainage waters can be coupled to livestock enterprises in sustainable ways, drainage water could become an asset rather than a problem.