California Agriculture, November 1950
Volume 4, Number 11
Pest control study with systemic insecticides
Systemic insecticides: Control of plant feeding pests by poisoning plant juices studied
by Robert L. Metcalf, Robert B. Carlson
Not available – first paragraph follows: Systemic insecticides— compounds which can be absorbed readily by plant foliage and roots and subsequently trans-located throughout the plant—render the plant tissues poisonous or unpalatable to juice feeding insect pests.
Olive flower-bud formation: Nutrients essential to tree during March and April when flower-buds are forming tests show
by H. T. Hartmann
Not available – first paragraph follows: A critical stage in the production of olives—as in any fruit crop—is when the flower parts are forming in the buds.
Analyses of irrigation water: Waters of six rivers and nine wells in California studied to establish their usefulness for irrigation
by L. D. Doneen
This is the second of two articles on the quality of water and plant tolerance to salts. The previous article, in the October issue of California Agriculture, explained the classification of irrigation waters in three groups: Class I. Excellent to Good—Safe and suitable for most plants under any condition of soil and climate. Class II. Good to Injurious—Possibly harmful for certain crops under certain conditions of soil OT climate. Class III. Injurious to Unsatisfactory—Probably harmful to most crops and unsatisfactory for all but the most tolerant.
Smog in the south coastal area: Injury to herbaceous plants in the affected area found to be result of air pollution by gases and aerosols
by John T. Middleton, J. B. Kendrick, H. W. Schwalm
Not available – first paragraph follows: Smog injury to crops in Los Angeles County in 1949 amounted to an estimated loss of $479,495.00.
Diagnoses of insect diseases: Microbial infections in insects diagnosed as part of the research in developing new ways of controlling crop pests
by Edward A. Steinhaus
Not available – first paragraph follows: The first successful experiments in microbial control of a California crop pest had their beginning in the diagnostic part of the laboratory of insect pathology in the Division of Biological Control in Berkeley.
Orange fruit size: Five-year study of small fruit size covered 429 groves in six counties
by J. C. Johnston
Not available – first paragraph follows: Two outstanding causes of small fruit size in oranges are poor physical conditions of the soil and inadequate irrigation.
Wind machines cost analysis: Cost records studied for effectiveness of machines in frost protection, operation and maintenance
by Harold E. Wahlberg
Not available – first paragraph follows: Conflicting reports on the effectiveness of wind machines—installed as a substitute for the artificial heating of citrus orchards—prompted a study of the efficiency of the machines, under Orange County conditions.
Farm prices and production: Index numbers of prices received by farmers and of production indicate relative changes
by G. M. Kuznets