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Air pollution in the Los Angeles and San Francisco Bay areas of California causes damage to the foliage of many-plants and reduces the growth of a variety of glasshouse-grown crops.

The Nuevo peach has yellow nonmelting flesh, sweet-flavored and of medium acidity. It is intended for home or commercial processing in areas where winter chilling is insufficient for the standard varieties. It was satisfactory in a commercial canning test at Hemet, Riverside County.

Control of medusahead (Elymus caput-medusae) on rangeland is a major problem on many acres in California and other western states. Where this grass covers large areas and spraying or mowing is not feasible, burning has been extensively used. The purpose of burning is to destroy the seed in the head before it shatters and is deposited on the ground. Because medusahead is an annual plant it depends on the current seed crop to perpetuate itself. In many circumstances, where burning is properly accomplished, the medusahead stand will be reduced to a very low percentage during the next growing season.

Data from two years of trials—using both air and ground application—indicate that zineb, maneb, Phaltan, and captan fungicides gave good control of early blight (Alternaria solani) on sprinkler irrigated potatoes during the fall season. Tests were conducted in the Hemet Valley, Riverside County.

Plastic levees offer a new approach to water control and distribution in rice field irrigation. Field and plot test information obtained during the past two years has proved the physical feasibility of this technique. Studies are continuing on the economic feasibility of plastic levees and on the possibilities of developing a machine which could install these levees in one or two operations.

The use of certain herbicides for weed control is often restricted because of their persistence in the soil and the detrimental effect on subsequent crops. This is particularly true of short-season vegetables where a second crop may follow in from three to four months. In southern California tests two of the urea herbicides, neburon and monuron, were found to disappear relatively slowly. From 4 to 5 months were required for monuron and 8 to 9 months for neburon to fall to the 50 per cent disappearance levels.

Mixing 5 per cent red bell pepper juice into regular tomato cocktail offers processors a new flavor possibility as well as significantly increasing both vitamin A and C content of the canned juice.

Conversion of chaparral-covered watersheds to native grasses and forbs resulted in production of significantly more surface water runoff—without appreciable erosion after conversion—in southern California test areas. Grazing potential of the watersheds was also greatly increased and wildfire hazards reduced.

Both greenhouse and field results indicate that the ammonium acetate-dithizone test may be useful in identifying soil areas likely to be zinc deficient. Tentatively, 0.5 ppm (parts per million) is believed to be a critical level below which a zinc response might be expected on sensitive field and vegetable crops.