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A well-known pest of woody ornamentals, the weevil is now found in some south central coast vineyards. Cardboard tree wraps around vine trunks provide a simple monitoring technique for timing selective sprays to control adults before they lay eggs.

Dissolved gypsum and calcium nitrate each increased infiltration rates over the control for each of the 15 irrigations to which they were added. An equivalent amount of gypsum spread on the surface at the beginning of the experiment had the same beneficial effect for only 10 irrigations.

Agricultural sustainability has different meanings, depending on the context. But many people share a concern that the current, highly productive agricultural system has become so dependent on agri-chemicals that problems have emerged affecting the environment, food safety, farm-worker safety, and production costs. There are hindrances to change, however, and research on low-energy-input farming is still developing. A broad approach is required, taking into consideration not only the farm production system but also the need to “sustain” society as a whole.

Initial results from greenhouse experiments suggest that some plants are able to lower selenium concentrations in soils by up to 50%. Use of these plant species to reduce concentrations to acceptable levels in problem soils on the west side of the San Joaquin Valley may be economically feasible.

Several registered fungicides evaluated over a 7-year period in the southern San Joaquin Valley controlled the disease on fruit. Captan, captatol, and ziram preceded by dormant copper provided the most consistent control. Fungicides protected against yield losses in a heavy-disease year but had no effect on yields when the disease was not prevalent.

For as long as there have been humans in the Central Valley grasslands, they have hunted, fished, and gathered plant or animal life for consumption. “Foraging” became a health concern with the evidence of selenium accumulation at Kesterson Reservoir. A survey suggests that a large number and variety of people forage. The amounts and frequency of consumption are probably not great enough to be a health hazard to any one person or group, but there is still some cause for concern.

Potassium-deficiency symptoms in cotton are widespread in California and become most apparent in leaves during heavy demand by developing bolls. Potassium fertilizers may reduce the problem, but the main cause may be pathogenic organisms in the soil. Soil solarization, which controls soilborne pathogens of cotton, also controls the potassium deficiency problem without appreciable changes in the availability of potassium to cotton roots.

Whole cull pistachio nuts appear to be acceptable to cattle and sheep as part of their daily rations. Research indicates that cattle can be fed up to 20% of the daily ration without refusal, but this may be too high for sheep.

Range cattle obtain vitamin A from carotenoids in green plants. In northern California's foothill ranges, carotenoids are destroyed as forage dries in the summer. Tests of liver and blood plasma in grazing cattle indicated that mature breeding cows can store enough vitamin A during the green season to meet later needs. Heifers on their first calf, however, may need vitamin A supplementation.

Kidney beans become very susceptible to mechanical damage at moisture levels below 11.5% to 12%. It is important, therefore, to harvest early at higher moisture and to minimize mechanical impact during threshing and warehousing operations.

The 1986 immigration reform act allows “replenishment agricultural workers” to obtain legal resident status beginning October 1989, if farm labor shortages are projected. Federal agencies have to decide how many RAWs to admit and who they will be. Rules recently developed by the Departments of Labor, Agriculture, and Justice to generate data for these determinations hold great significance for employers, workers, and researchers.

Because of their worldwide distribution and numbers, future introductions of fruit flies into California are inevitable. Infestations of economically important pests, including but not limited to the medfly, Mexican fruit fly, and oriental fruit fly, are expensive to treat, and their elimination is seldom certain. Researchers are seeking to improve detection and control methods.