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Head lettuce is a major crop in California with over 100,000 acres harvested annually-accounting for about 60% of the nation's total supply. With labor problems CI certainty when the Mexican bracero program is discontinued, harvest mechanization efforts have taken on new importance. The University-designed experimental machine described in this report is capable of selectively harvesting mature heads of lettuce without' injury, and allows many handling possibilities after cutting. The number of fruits and vegetables harvested by machine has increased rapidly along with changing conditions in farm economics and labar procurement. Tomatoes and prunes are among the most recent of these crops to pass from the experimental to the commercial harvesting stage. Each crop presents special problems in removal of fruit from the plant and in subsequent handling. One problem common to many such crops is the need for selective-and often several-harvests of fruit as it matures, without damaging remaining plants. The University-designed harvesters for lettuce and cantaloupes, described here, show two different approaches to selective harvesting.

The experimental harvester for cantaloupes described in this report has a conveyor belt allowing vines to be lifted as many as six or seven times with tensionremoval of ripe fruit without damage to melons remaining, or plants.

This progress report of research indicates lygus bug control is possible by strip cutting alfalfa to keep the bugs in the alfalfa where they do little harm, and allow survival of natural enemies. Further investigations are necessary, particularly on the agronomic, economic and long-range ecological aspects of strip cutting, before the pros and cons of this harvesting method can be fully evaluated. However, the end result could well be a very considerable saving to California farmers, and perhaps wen more importantly, a significant reduction in pesticide hazard problems.

The stump sprout control tests reported here were initiated November 14, 1960, and were completed on February 14, 1961. All of the trees on the periphery of Watershed No. 2 at the Hop-land Field Station were used in this study. Most of the trees were blue oak; however, sufficient black oak existed on the area to obtain some information about treatments upon this species. The treatments were conducted in solid blocks, with one complete set of treatments being located on the southern periphery of the watershed and the other set or replication on the northern boundary.

Total population in Sacramento County increased 81 % between 1950 and 1960; but farm population decreased 51 %. Projections for Sacramento County indicate a population of 1 million before 1980 and about 2.5 million around the year 2000. This rapid urban growth already has had far-reaching effects on agriculture. Not only does urban growth require additional land, but it has effects on the use of land that remains in agriculture. This study reviews and analyzes several of these effects.

Tests show that a number of inert, porous, non-toxic powders and granulated materials provide suitable carriers for concentrated wetting agents. The application of powdered or granular forms of wetting agents by plane or helicopter appears feasible. Local applications by mechanical spreaders and hand-dusting equipment are also possible.

Tioga, a new high-yielding strawberry variety for California, has been released to nurserymen for unrestricted propagation. Limited increases were grown by nurserymen during 1963. Requests for plants should be directed to commercial nurseries or plant brokers. Virus-free stock eligible for entry in the California Strawberry Certification Program is available for nurserymen from the Foundation Plant Materials Service, University of California, Davis.

Under-tree sprinkling for frost protection in deciduous orchards involves a great amount of risk with only partial protection possible-as compared with no risk involved in the overhead sprinkling method, under practically all California spring frost weather conditions.