Calag Archive

Sticktights that remain in almond trees after harvest serve not only as overwintering sites, but also as the only source of food for the spring generation of the navel orangeworm.

The face fly, Musca autumnalis, now an important pest of livestock, and sometimes of man, throughout much of the United States, has spread as far west as Washington and Oregon; and its invasion of California now appears imminent. This fly differs from its close relative the house fly, Musca domestica, in that its immature stages develop only in fresh cattle droppings, rather than in manure piles, garbage, etc. Investigations of the unique insect community of which this fly is a member indicate that the face fly may soon become established throughout much of the state. This report details movement of the fly into western states, the insect's habits, and control possibilities.

Flower bud formation in various Prunus species can be curtailed or completely prevented with use of gibberellic acid—depending upon the concentration used. Many of the important tree fruit crops grown in California, including peach, plum, cherry, and apricot belong to this genus. These trials indicated that gibberellic acid sprays may be useful in reducing or eliminating hand thinning and in controlling crop levels in cling peaches.

Bensulide (Prefar) was the most promising of the preplant herbicides tested for selective weed control in melons. It is not yet registered, however, and is not recommended by the University of California. Of the postplant herbicides tested, trifluralin (Treflan) and nitralin (Planavin) gave commercial weed control with considerable safety, when incorporated with a rolling cultivator after planting. Trifluralin is registered for use in curcurbits (except for watermelon) at the “lay-by” or 3-to 4-leaf stage of development. Planavin is not registered—and neither chemical is recommended for use by the University of California at this time.

Powdery mildew (caused by the fungus Sphaerotheca fuliginea) of squash and cucumber can be a serious economic problem wherever these plants are grown in California. Heavily infected plants may decline in vigor prematurely with subsequent loss of yield. The studies reported here are of experiments with fungicides used for control of powdery mildew in both squash and cucumber. Some of the materials mentioned are not registered for use in these crops and the information is not to be considered a recommendation of the University of California or USDA.

Barley swathed within a moisture range of 51 to 31% was not significantly lower in protein content or germination potential, as compared with standing grain in these tests. However, yield reductions occurred at all cuttings within this range. Grain quality was related to the moisture content at which the crop was swathed. Results of moisture determinations based on whole-head samples agreed closely with results obtained on a kernel basis.

Vacuum Recordings made at cow-side during milking are highly effective in detecting milking system inadequacies and malfunctions. This widely used technique is an outgrowth of research at University of California School of Veterinary Medicine, Davis, as early as 1957. Researchers Schalm and Noorlander conducted their investigations by recording vacuum levels with a strain gage amplifier. This electronic instrument is extremely sensitive and its measurements are accepted as the standard for accuracy. However, for use in the milking barn this equipment has several disadvantages— it is costly, complex, and fragile—and consequently, is seldom available.