Citrus problems in West Fresno County

The possibility of growing citrus crops on the eastern slopes of the coast range in Fresno County has gained considerable attention since the cotton allotment reductions. The deep, well-drained, fertile soil; a good water supply from the San Luis reservoir and canal system; and a possible thermal belt are some of the advantages found in the area. However, many questions remain to be answered. The citrus specialists at Riverside, cooperating with the Fresno County farm advisor, are currently engaged in investigations to determine whether the high boron levels in this area might preclude citrus crops; how weather conditions there would affect citrus; and which of the commonly used scion-rootstock combinations could be adapted. Preliminary studies reported here indicate: (1) that proper leaching with good quality water could reduce boron damage; (2) that high wind velocities probably can be controlled with windbreaks; and (3) that of the 47 scion-root-stock combinations observed, Valencia and navel on trifoliate orange rootstock made the best showing. However, much research remains to be accomplished before definite conclusions can be stated.