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Monthly aerifying was an aid to controlling the development of dry spots and did not cause cumulative injury on a Seaside bentgrass green during 1963 summer tests in San Bernardino County. Verticutting during the summer heat caused some injury to this fine turfgrass, but was also of some value in controlling dry spot development as thatch built up late in the season. Wetting agents aided in controlling dry spot development, but were detrimental to the appearance of the turf on this green. The tests also proved that it is possible to conduct complex experimental work on golf greens, if the management and players understand the importance of the work and the research is scheduled to cause a minimum of inconvenience to the golfers. Inexperienced judges were found capable of appraising visual effects of different management practices on the turf.

Leaching of soluble salts—necessary for sustained irrigated agriculture—is accomplished by allowing some surface applied water to pass completely through the crop root zone. Although leaching is often carried out to a limited degree with each application of irrigation water, it is sometimes only possible to leach annually or less frequently, depending upon the crop grown, water supply and other local conditions.

Sugar beets responded to decreasing fall temperatures with an abrupt slowdown in both root and top growth but also with increases in the sucrose Concentration of roots, according to this test in northern 10s Angeles County. Plants that became deficient in nitrogen in mid-August produced roots as well as those kept supplied with nitrogen throughout the fall; and on December 5, roots of N-deficient plants contained 2.7 percentage points more sucrose than roots of high-nitrogen plants.

Frost damage to the floral parts of grain heads (prior to, during and immediately after pollination) is surprisingly common in California, other mountain states, and many cereal-growing areas in the world. Development of early maturing varieties has intensified the problem in all areas, particularly where cereals are fall sown. Many seed and fruit crops also can be damaged by frost. Most plants are extremely sensitive to temperature in stages of rapid growth and reproduction. This is especially true of plant reproductive organs.

The effectiveness of plastic and petroleum mulches did not change in tests at two different locations on two different soil types in San Joaquin Valley cotton fields. Higher soil temperatures generated by all of the mulch test treatments resulted in earlier cotton germination and faster development, but ultimate plant sizes were the same. The mulches did not affect cotton quality, but shifted a greater percentage of the yield into the first picking. Although yield increases alone may not return the cost of treatment, reductions in hand labor made possible through precision planting as part of the mulching operation offer some compensation.