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Tower mounted wind machines raise orchard temperatures largely by the forced mixing of cold orchard air with the warmer air overhead. However, tests in an almond orchard in the Chico area –in 1955 and 1957–showed that the air jet from tower mounted machines had difficulty in penetrating the tree canopy –typical of deciduous orchards–formed by the intertwining of branches of adjacent trees. Underneath the tree canopy deciduous orchards are relatively open but growers report that most frost damage occurs in the lower part of the trees.

The first California certified seed of Svälof Fourex spring rye–introduced from Sweden–is expected to become available for commercial use after the 1959 harvest.

Techniques of Field Sampling and Plant Analysis A field of alfalfa should be divided into two or more segments of not over 20 acres each. Sampling should be done at one-tenth bloom or when one out of 10 plants has some open blossoms. Samples should be taken by walking across the center of the area collecting one complete stem of alfalfa at 35 different locations distributed at equal intervals. The mid-stem tissue is obtained by cutting out the middle third of the stem and stripping the leaves from it. Samples should be air dried or oven dried at 158°F and ground to pass a 40-mesh screen. Analysis for acid soluble phosphorus is made as described on page 49 of California Agricultural Experiment Station Bulletin 766. A free copy of Bulletin 766 may be obtained at the local Farm Advisor's Office or by a request sent to Agricultural Publications, 207 University Hall, University of California, Berkeley 4, California.

By-product lime–from beet sugar refineries–is used frequently in the Central Valley of California, to improve the physical condition of the soil, particularly for seedbed preparation. Lime is commonly applied to acid soils to decrease the acidity but the pH–relative acidity-alkalinity–of most of the Central Valley soils is neutral to slightly alkaline.

Young rice plants damaged by the rice water weevil–Lissorhoptrus oryzophilus Kuschel–were found in fields near Biggs on June 1, 1959.

Damage to grain sorghum by the corn earworm–Heliothis zea (Boddie) –has been especially severe in Butte and Glenn counties. Certain fields examined in 1957 and 1958 showed 90%-99% of the heads to be infested. Usually 1–4 larvae per head were found although some heads had 10-16 larvae.

Based on results of an eight-year study, a 12-month alternation strip-treatment seems to be a feasible control program throughout Orange County areas where purple scale–Lepidosaphes beckii (Newm.)–is the primary pest on oranges.