All Issues

Both stalk elongation rates and dry matter analyses of sugar cane irrigated with Colorado River water indicate that such areas should be used for this crop only when soils are well drained and relatively salt free.

Calmar is a new crisphead lettuce belonging to the traditional Great Lakes varietal type. It is equal to or surpasses Great Lakes 118 in many characteristics, including uniformity of maturity, and is also resistant to downy mildew. About 10,000 acres of Calmar were estimated to have been planted for harvest in 1964 in the Salinas-Watsonville district and a larger acreage is predicted for the 1965 season.

Iron deficiency in plants, characterized by yellowing of the leaves, indicates that chlorophyll, the green coloring matter, is not being produced. While iron is not a constituent of chlorophyll, studies with algae indicate that iron functions in the synthesis of a specific kind of ribonucleic acid, which in turn regulates chlorophyll synthesis through a chain of reactions which as yet are largely unknown.

Drainage problems have been corrected on 45 Tulelake Basin farms in Modoc and Siskiyou counties through installations of tile drain lines. Studies have shown excellent reductions of soil salinity and high water tables, with no failures reported since installation of the drains over five years ago.

Shaker-clamp stresses on fruit and nut trees during mechanical harvesting, which can result in bark injury and susceptibility to disease, were measured under a variety of conditions in these continuing studies. Some of the variables found to affect bark injuries include moisture in both soil and bark, varietal differences, and tree age.

to reduce shaker-clamp injuries on fruit and nut trees as described in a companion article in this issue of California Agriculture, tests were made to check the feasibility of using permanently installed fasteners for shaker attachments. This has the advantage of transmitting the shaking force through the fastener to the structural wood rather than through the vulnerable bark and growing tissue

About 20% of California's dried prune crop will be processed through parallel-flow dehydrators this year—a technique developed by University researchers that allows a 50% increase in seasonal capacity of conventional dehydrators, with no important differences in quality of the dried prunes. The new system involves moving the cars of prune dehydration trays through conventional drying tunnels with the hot air flow rather than against it. This operation exposes the moist prunes to the hottest air at the start of the drying process when higher temperatures are desired, rather than when nearly dry as they leave the tunnel. The new technique has also made feasible complete time-clock automation of dehydration tunnels.

salinas valley pumping costs vary widely depending upon their location, with great differences in pumping costs often occurring over relatively short distances. Yield of ground water aquifers, proximity to the river, and ground elevation are the basic factors determining the pumping lift at any particular location in the Valley. A sample of 1,562 well tests made by the Pacific Gas and Electric Company showed that pump lifts in the Salinas Valley range from less than 25 ft near the Salinas River to over 350 ft on the bench lands near the eastern foothills.