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Limited trials with Promone, a progesterone-like hormone, showed considerable promise for increasing weight gains and feed efficiency of heifers in the feedlot. The trial reported here tested the feedlot performance of heifers when implanted with 200 and 400 mg of Promone, as compared with stilbestrol implants and with a control group.

Tests reported here indicate that mechanical clipping of tomato plants may be used satisfactorily to spread harvest dates and obtain plant uniformity. The delay in harvest may be 7 to 14 days depending upon the physiological age of the plants at time of clipping. The first-flower-cluster clipping gave a 7-day delay whereas clipping at the second- and third-flower-cluster stage gave a 14-day delay. A later clipping treatment —when fruits had first begun to form (pea size)—was found to be too late and reduced yields. It is important that an irrigation be made immediately following the clipping. The new growth is rapid, producing a more vigorous and somewhat larger plant.

THE CONTRA COSTA COUNTY Drainage Project resulted from a request made of the Agricultural Extension Service at a county planning meeting held in 1964. The project involved the cooperation of the Extension Service, East Contra Costa Irrigation District, U. S. Soil Conservation Service, and USDA's Agricultural Stabilization Committee. The main objectives were: (1) to test spacing intervals for tile lines under soil conditions in the Brentwood and Byron areas of Contra Costa County as a basis for planning drainage projects for the two areas; (2)   to test various tile materials with both gravel and glass fiber envelopes; and (3)   to correct a serious drainage situation in a walnut orchard in Brentwood.

THOMPSON SEEDLESS GRAPES must bethinned to allow production of loose clusters of well-developed berries. In recent years, the usual shatter-stage thinning has become a major labor-consuming operation for the grower. Hand thinning during the prebloom period, while foliage is light, clusters are small, and shoots are 12 to 16 inches long, would be economically desirable but has not been practical because of the increase in berry set, resulting in tight clusters.

New systems for greenhouse management have been introduced in recent years that necessitate changes in some of the traditional methods of growing greenhouse crops. Evaporative cooling. infra-red heating, elevated levels of C0₂, and positive ventilation may each, if improperly used, result in changes in plant response that are not necessarily to the grower's advantage. When one aspect of a plant's environment is altered, it is necessary to reevaluate the total production system to bring all factors back into balance.

Following A change in the water supply used for irrigation and misting–from a shallow well (400 ft) to a deeper well (800 ft)–a large California chrysanthemum producer experienced extreme difficulty in rooting the cuttings. Early symptoms appeared as a loss of root hairs and small rootlets, and as a reddening of portions of the roots (photo 1). As severity increased, the tips beyond the reddened areas died and the number of roots increased. These failed to elongate so that in the most severely injured cuttings, only a tuft of short, reddish-brown roots was produced (photo 2). Except for the failure to elongate, there were no symptoms on the above-ground portions of most varieties.

Rhizopus soft rot, a serious breakdown problem in sweet potatoes during marketing, can be substantially reduced by use of the fungicides Botran or SOPP, when treatment is accompanied by proper handling practices.