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The following brief article is based on a detailed study by the same authors to be published as a mimeographed report of the Guanine Foundation of Agicdtural Economics

Dangerous fire situations may be created in areas of second-growth ponderosa pine left unburned for a number of years and thereby permitting a buildup of dead shrubs, needles and other litter—the rough—as well as overpopulations of small trees. When such areas are burned by wildfire in summer, or fall, all living vegetation is apt to be killed and a poor land condition results.

Range wether lambs sired by Suffolk rams gained slightly faster than lambs— from similar ewes—sired by Corriedale rams, during the fattening period on native range or irrigated pasture.

Plant injury resulting from the use of aqua ammonia or anhydrous ammonia as sources of nitrogen has occurred when the materials were placed relatively close to young plants and—usually—at high rate of application. Ammonia injury reduces plant growth, delays maturity and yields are unsatisfactory. Usually injury is characterized by a burning-off of the smaller plant roots and by a yellowing or browning of the larger roots.

Maintenance of high concentrations of nitrate in soil and solution cultures induced better growth in Valencia orange trees than that produced by low nitrate levels.

Soil samples taken in 1955—from a 38-year-old citrus orchard—were compared with soil samples taken in 1927 when a long-term fertility trial with various fertilizer treatments was started. The main factors known to have influenced yields in the fertility trial are available nitrogen and structural conditions of the soil. The application of phosphorus fertilizers did not influence the yields or the quality of the fruit.

Fruit size measurements—to compare the effects of oil and parathion sprays on orange fruit size and quality— were made in nine navel and six Valencia groves in southern California during the years of 1953 to 1956.

Three varieties of California-grown avocados-Fuerte, Anaheim, and Hass— of four crop years, were examined for content of most of the B vitamins. The fat and water contents, and the effect of various periods of refrigeration and ripening at room temperatures also were given attention.