California Agriculture, March-April 1988
Volume 42, Number 2
peer-reviewed research articles
Sustained-release bolus for deworming dairy heifers
by Thomas A. Shultz , E. Michael Huffman , Norman F. Baker
Abstract Not Available – First paragraph follows:A major source of gastrointestinal worm infestation of grazing heifers is larvae that have survived the winter on pasture grass. When these larvae are swallowed and mature inside the heifer, they produce eggs that are shed in the feces, resulting in a higher pasture contamination later in the grazing season. To break this recycling of pasture worm infestations, multiple deworming is needed. This adds labor and other costs, since the heifers are on pasture and may not be easily accessible.
What about 4-H?
by Robert E. Savage
Abstract Not Available – First paragraph follows:Modoc Countv's 4-H re-enrollment began declining inihe early 1980s from a 20-year average of 70 percent to 59 percent in 1983. Since the percentage of return membership reflects the degree to which the 4-H program is meeting clientele needs, re-enrollment is the major indicator of the program's quality. To learn why youth remain in, or leave, 4-H in Modoc County, I conducted a study over a three-year period, 1984-86.
The epidemiology of powdery mildew on tomatoes
by James C. Correll , Thomas R. Gordon , Vern J. Elliott
Fresh market tomatoes are susceptible but yields don't seem to be affected
Biological control of leafminers on greenhouse marigolds
by Kevin M. Heinz , Julie P. Newman , Michael P. Parrella
In greenhouse marigolds grown for seed, a parasitic wasp suppressed leafminers for two months after establishment
Predicting vineyard pruner performance
by Gregory Encina Billikopf
A job-sample test showed high correlation with work performance
A new marketing era for California specialty crops
by Harold O. Carter , Carole Nuckton
The rules may have changed, but California producers of specialty crops seem to have reason for cautious optimism, at least for the near term. The longer term outlook is uncertain and may depend on new marketing techniques and new technology.
Added fat in dairy feed decreases milk protein
by Edward J. DePeters , Scott J. Taylor , Curt M. Finley , Thomas R. Famula
The practice may reduce rather than increase cheese yield
Estimating saline water table contributions to crop water use
by Mark E. Grismer , Timothy K. Gates
Abstract Not Available – First paragraph follows:Researchers in several western states have found that, under arid conditions, water tables can supply as much as 60 to 70 percent of a crop's water requirement. Use of high water tables reduces irrigation needs, lowers production costs, reduces deep seepage losses, and decreases the volume of drainage water requiring disposal. Successful use of the water table also depends on the soil's water retention and transmitting properties, evapotranspiration (ET) demand, distribution of the plant root system, and salinity and toxic ion effects on crop growth. Under field conditions, many of these factors are part of the overall crop response to the saline.
A new disease of myrtle
by Amy Lutz , Albert O. Paulus , Donald M. Ferrin , Jerry A. Nelson
Cylindrocladium root and crown rot, once established, is difficult to control
Blacklight monitoring of two avocado insect pests
by J. Blair Bailey , Michael P. Hoffmann , Kirk N. Olsen
Early summer flights are generally the largest, and likely to cause the most damage
Diagnosing nutrient needs of garlic
by Kent B. Tyler , Donald M. May , John P. Guerard , David Ririe , James J. Hatakeda
Phosphorus and zinc fertilizers are rarely required. Only moderate amounts of nitrogen are needed for top yields.
New psyllid pest of California pepper tree
by James A. Downer , Pavel Svihra , Richard H. Molinar , Jack B. Fraser , Carlton S. Koehler
Abstract Not Available – First paragraph follows:A new psyllid pest of California pepper trees was first discovered in Long Beach, California, in July 1984. Since then, the insect has spread rapidly, particularly in coastal areas, and now occurs from San Diego County to the San Francisco Bay region. There are scattered records of its occurrence inland in San Bernardino and Kern counties.
editorial, news, letters & science briefs
Agricultural technology: Put the genie back in the bottle?
by Kenneth R. Farrell