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Millions of acres of California rangelands that could otherwise be improved by re-seeding are located on terrain that is steep, erodable, or too rocky for cultivation. Recent research has shown that these ranges can be successfully seeded by spraying the resident annual vegetation with paraquat and planting immediately. Spraying in bands was shown to give adequate weed control. Special seeding equipment has been developed to allow spraying, fertilizing, and planting in one operation on any terrain that can be traversed by a crawler tractor. This article is a progress report of experimental use of paraquat on California rangelands. Further investigation is necessary before federal registration or University of California recommendation will be granted for use of this herbicide on rangeland.

VERTICILLIUM wilt, a serious disease resulting from infection by a soil-borne fungus, is important in California on many crops including potatoes, strawberries, cotton, cherries, apricots, chrysanthemums, and roses. Although it is a more important disease in greenhouse roses grown for cut flowers, it does not cause much trouble in roses grown for the home garden. This phenomenon has been difficult to understand because they are both propagated by budding into young, rooted cuttings of rootstocks grown under the same cultural conditions, and in the same soil types, and frequently in the same fields. Another point of confusion is that greenhouse roses are commonly grown on Manetti rootstock, which is resistant to Verticillium fungus, whereas garden roses are grown on Odorata, Dr. Huey (also called Shafter), Burr Multi-flora or Ragged Robin, all of which are more susceptible than is Manetti.

Soaking Duke variety avocado seeds in high concentrations of gibberellic acid for 24 hours prior to planting increased the rate of germination, seedling height, and stem diameter.

SPRINKLER IRRIGATION for tree crops in the San Joaquin Valley has increased rapidly during the past ten years, particularly in areas planted to citrus. While no exact figures are obtainable, it is estimated that more than 20,000 of the 100,000 acres in citrus are now irrigated by sprinklers- Large acreages of walnuts, olives, and deciduous fruit are also being irrigated by sprinklers. Nearly all of this increase in sprinkler irrigation involves systems using the new hose-pull or overhead methods, as described in this study.

Age at castration appears to influence growth rate of male cattle. The higher pre-weaning weight gains of bulls suggest that the male hormone is an influencing growth factor. However, post-weaning weight gains are lower in bulls castrated at eight months, which tends to nullify their pre-weaning advantage. Stress caused by the operation may have been a factor in this response. Differences in weight gains associated with diethylstilbestrol treatment were obtained whenever used in these tests. This is a progress report of experimental use of diethylstilbestrol in tests with early and late castrates to improve weight gains—a practice not presently recommended by the University of California.

An over-wintering refuge for egg parasites of grape leafhoppers showed a marked effect in vineyards at a distance of 3.5 miles and its influence could be traced over 4 miles, according to preliminary surveys.