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Less lifting by hand, fewer workers, and lower costs per ton for the grower, were obvious results shown in this analysis of mechanical aids and bulk handling methods for all of the Fresno County raisin pickup and boxing operations studied. In six of the eight operations using mechanical aids, a savings of $2 or more per ton was realized—over and above the cost of equipment. The switch from field boxes to bulk handling bins, alone, was an important factor in both labor saving and cost reduction. However, it was impossible in this study to separate benefits of bulk handling from benefits of pickup machines, because of the lack of uniformity between individual grower systems.

The horn fly, Haematobia irritans, is a permanent, blood-sucking parasite of livestock which, under dense populations may be responsible for reduction in either weight gains or in milk production. Spraying is the most common method of horn fly control but involves capital investment in power-spray equipment, excessive labor for repetitive spray treatments, and in some instances, considerable animal stress. An earlier study showed the effectiveness of Ronnel when this animal systemic insecticide was mixed with cottonseed supplement and fed throughout the summer season. Cattle grub control also was obtained the following winter, but high costs (three cents per head per day) and the methods of supplementing summer rations were not applicable to all winter livestock management operations. For these reasons, and because of the threat of a face fly invasion of California, the use of insecticidal dust-charged burlap sacks (“dust bags”) was investigated in 1966 and successfully field tested during the next two years.

THE COTTON LEAF PERFORATOR, Buc culatrix thurberiella Busck, a pest of cotton native to the southwestern United States, is apparently restricted in its feeding to wild and cultivated species of Gossypium. In the past this tiny insect has been the cause of severe damage to commercial cotton in the desert areas of California and was one of the reasons for the cessation of cotton production in southern California in the 1930's. It was not until the introduction of the chlorinated hydrocarbon insecticides in 1946-48 that cotton production was resumed in these areas.

Soybean materials that showed most tolerance to the two-spotted mite, Tetranychus urticae K., in greenhouse tests were USDA Plant Introduction P.I. 88,492 and UC-228.

Yield of pod sizes 1 through 4, expressed in terms of percentage of total yield, appears to be a practical measure of maturity for GV 50, Blue Lake 274, and Salem; but a different standard is required for Green Isle. For all four varieties in this trial, however, yield of pod sizes 1 through 4, expressed in terms of percentage of total yield, had a straight-line relationship, suggesting that field sampling for two or three days several days ahead of harvest time can be used to predict when a desired maturity (expressed in terms of percentage of pod sizes 1 through 4) will be reached.

THE NEW GROWTH REGULATOR, Ethrel (2-chloroethyl phosphonic acid), is similar in action to ethylene in its effects on various plant processes: it accelerates post-harvest ripening of tomato, banana, and honeydew melon fruits; it induces flowering in pineapple plants; it causes female flower differentiation in cucumber plants; and it acts as a thinning agent by accelerating abscission of flowers and young fruit in certain trees and by loosening fruit at harvest to aid mechanical harvesting. These experiments were initiated to examine the effects of Ethrel on growth and maturation of tomato fruit on the vine under both greenhouse and field conditions.