California Agriculture, May-June 1989
Volume 43, Number 3
75th anniversary of Cooperative Extension
peer-reviewed research articles
Simple monitoring of black vine weevil in vineyards
by Phil A. Phillips
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.
Calcium amendments for water penetration in flooding systems
by William E. Wildman, William H. Krueger, Richard E. Pelton
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: An overview and research assessment
by Harold O. Carter
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.
Plants that remove selenium from soils
by Gary Banuelos, Gerrit Schrale
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.
Effect of fungicides on shot hole disease of almonds
by Beth L. Teviotdale, Mario Viveros, Mark W. Freeman, G. Steven Sibbett
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.
Foraging in Central Valley agricultural drainage areas
by Mark Campbell, L. Clair Christensen
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.
Control of potassium deficiency syndrome in cotton by soil solarization
by William L. Weir, Richard H. Garber, James J. Stapleton, Reuben Felix-Gastelum, Roland J. Wakeman, James E. DeVay
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.
Pistachio culls acceptable in livestock feed
by John L. Hull, John R. Dunbar, Edward J. DePeters, H. Rocky Teranishi, Neil K. McDougald
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.
Seasonal changes may cause vitamin A deficiency in range heifers
by James G. Morris, Teresa I. Iglesias, Myung-Hee Kang
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.
Effect of harvesting and handling on damage in canned kidney beans
by W. Mick Canevari, Robert G. Curley, Michael Murray, Clay Brooks, Gerald Knutson
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.
SAW employment data and the need for RAWs
by Howard R. Rosenberg
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.
Exotic fruit fly pests and California agriculture
by James R. Carey, Robert V. Dowell
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.
editorial, news, letters & science briefs
Cooperative Extension: A tradition of investing in California's future
by Kenneth R. Farrell
Cooperative Extension at 75 People investing in California's future
4-H takes on new challenges
EFNEP makes a difference
by Gary A. Beall
New era for agricultural research in the San Joaquin Valley