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Big club 60 wheat, a product of the cooperative wheat breeding investigations of the California Agricultural Experiment Station and the U. S. Department of Agriculture, is now offered as an upgraded and branded replacement for Big Club 43. The upgrading involves improvement in the stem rust and barley yellow dwarf virus resistance. The brand is a purple straw.

Greenhouse and field studies with foliage sprays of 3 per cent ferrous sulfate solutions provided excellent correction of iron deficiencies in grain sorghum. Greatly increased yields also followed treatment in severely chlorotic areas. Although effective, the large amounts of ferrous or ferric sulfate required for soil applications proved economically impractical.

Avocado root rot, caused by the fungus Phytophthora cinnamomi, is the most important disease affecting avocados throughout the world. In California approximately 4,000 acres of avocados have been damaged. Trees growing in many types of soils have been affected, but the amount or extent of damage is much greater on some soils than on others. Previous investigators have pointed out that when the fungus is present, avocado trees growing in soils with poor internal drainage are most susceptible to root rot damage. Recent surveys have shown that the rate of spread is usually slow on deep, medium-textured (loam, fine sandy loam) soils and will range from moderate to rapid on many other soils.

Tests indicate that, under good conditions, 80 to 90 per cent removal of sweet cherries is possible by mechanical shaking. However, overcoming tree injury is essential to successful commercial use of tree shaking equipment. Improved clamping devices must be developed that will eliminate or minimize tree injury. Pruning and training adjustments will be required to facilitate use of mechanical harvesting equipment in the orchard and aid in fruit removal. Results of brining tests indicate that much of the bruising observed in the fresh fruit was not visible after brining, particularly when the fruit was placed in brine immediately after harvest. Shipping any of the mechanically harvested sweet cherry crop appears impractical today.

Trials conducted by the Department of Agronomy at Davis indicate the possibility of producing successful seed crops of several perennial grasses adapted to the Great Plains areas. Species showing the most promise include sideoats grama, weeping lovegrass, sand lovegrass, Boer lovegrass, and Lehmann lovegrass.

The squeeze machine method as evaluated for use on California and Texas wools, while not as accurate as the side sample method, is much easier, quicker, and less expensive. The animals can be rated in order of clean wool production more accurately than by grease weight, for high-shrinking wools. Rating of animals in this manner allows the breeder to choose those of higher productivity. The side sample method in most cases cannot be used by untrained personnel while the squeeze machine can. In high rainfall areas and with breeding stock producing high-yielding fleeces, grease fleece weight may equal or surpass the squeeze machine in accuracy. The machine does not appear to be of sufficient accuracy to determine shrinkage of wools for sales purposes.

Field trials have shown that Tedion is best used as a preventative spray, not as a curative treatment when mites are at treatment level. Seasonal programs should be planned for individual situations. If materials applied for other pests hold mites in check, Tedion can be used later in the season. If not, the material is best applied early, when weather conditions are less favorable for rapid mite increase.

Copper glycinate injections for control of molybdenum toxicity in livestock must be given at least twice (early and again at mid-season) during pasturing to be effective, according to Fresno County trials with beef and dairy cattle. The older method of adding copper sulphate to a self-fed mix was again proven satisfactory.

Crown rust is the major disease of the ryegrasses in California. It is particularly serious in the Coastal areas, and can be quite prevalent in the Central Valley in late spring.