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Practically all of California's commercial fruit acreage may be classed in one of two types of farming—fruit and mixed farming; or fruit, mixed farming and vegetable crops.

An outbreak of an insect tentatively identified as the spotted tentiform leaf miner—Lithocolletis crataegetta Clem.— occurred on the foliage of pear, apple and cherry orchards in northern California during the 1952 season.

Second of two articles on a study of yellow dwarf on cereols in California

Use of carbon dioxide in irrigation water had no significant effect toward the reclamation of black alkali soil in the cases of two Tulare County irrigation systems studied.

A photoelectric color sorter—which can duplicate manual sorting practices— has been developed for use in lemon packing houses.

Frost damage in a citrus orchard depends upon many factors, in addition to the minimum temperatures attained by the tree parts.

The value or need of potassium fertilization.—to increase Valencia orange fruit size—must be determined for each Valencia growing area because no critical level of leaf potassium can be universally assigned.

Air pollutants that cause typical smog damage—the silvering, bronzing, and spotting on many agricultural crops— are certain olefinic peroxides, formed when ozone reacts with the vapors of unsaturated hydrocarbons derived from gasoline and other petroleum products. In Los Angeles County alone, annual crop losses have exceeded $500,000 since 1949 when they were estimated to be $479,495.

The studies reported in the following article were conducted by Zaki Mahdi, a graduate student in Ornamental Horticulture, working under the direction of Professor Vernon T. Stoutemyer.