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Mechanical harvesting of Thompson Seedless raisin grapes by means of vibration has been under study at the University of California since 1968. During this time, machines have been developed for uniformly distributing the fruit onto a continuous paper tray (see photo) and for collecting the raisins from the tray after drying.

Citrus mealybug Planococcus citri (Risso) is a serious pest attacking many greenhouse grown crops. Cottony masses of the insect occur in great numbers on the growing tips of the branches of plants (see photo). The greatest numbers occur in the summer, fall, and early winter months, causing the most serious damage to plants. The mealybug is a gregarious feeder ultimately killing the tender shoots.

Sprinkling cattle, under shades, during the summer in the Imperial Valley for 1 minute every 30 minutes when the temperature was above 80°F (27°C)—resulted in significantly higher feed consumption and rate of gain, compared with cattle under shades but not sprinkled. Efficiency of feed conversion was not significantly improved over that of uncooled cattle (although the sprinkling treatment was favored). Sprinkling was as effective as a refrigerated air conditioned barn at 75°F (24°C) in one trial, and was more effective during a second trial. Sprinkling and refrigeration promoted greater comfort, as indicated by the prevention of increases in respiratory rate and body temperature observed in the afternoon with control cattle. Both uncooled and cooled cattle consumed more feed and gained more weight when alloted 40 sq ft per head of space than with 20 sq ft.

One application of plastic coated nitrate and ammoniacal nitrogen produced acceptable turfgrass for a nine-month period in these tests. This was comparable with turf produced by six low application rates of ammonium sulfate over the same period. One application of all other nitrogen sources produced acceptable turf for three to four months. Further work is needed with different grass genera and soil types.

From this series of studies it appears that sunflowers are well adapted (and needed) as a crop in the low desert valley areas. However, production with the varieties presently available is marginal-to-poor. Improvements in insect and disease resistance, coupled with benefits derived from use of hybrids, could make this a profitable crop for these areas in the near future.