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THERE ARE PRESENTLY SEVEN SPECIES OF Hippelates eye gnats which are adapted to varying climatic situations in California and southwestern United States. One species, Hippelates collusor (Townsend), is of wide-spread concern because it has become well adapted to year-around breeding in the hot interior agricultural areas of the Southwest, where field cultivation is practiced. Hippelates pusio Loew, also an agricultural breeder, is more restricted to the cooler climatic conditions on the coast. Two species, Hippelates robertsoni Sabrosky, and a recent invader from Mexico, H. impressus Becker, inhabit the mountains or lowlands in the spring. They cannot tolerate the extreme heat of summer in the lowlands of this region. Species that are of little annoyance or whose density is extremely low are H. microcentrus Coquillett, H. dorsalis Loew and H. hermsi Sabrosky.

CROSSES BETWEEN THE Aberdeen Angus, Hereford and Shorthorn breeds are becoming increasingly popular in the production of market calves—reflecting (in part) the impact of recently published results of experiment station trials of two-way and three-way crosses.

Sprays of maleic hydrazide, potassium salt of maleic hydrazide, and NIA 10637, (growth inhibitors) effectively inhibited top regrowth of top-pruned lemon trees in Ventura County tests. These compounds have not been registered for use on citrus, however, and cannot be recommended for use at this time.

Los Angeles Basin smog, caused principally by automobiles, consists of ozone, oxides of nitrogen, carbon monoxide and peroxyacyl nitrates plus some fluorides and sulfur oxides. It causes much leaf injury to leafy vegetables, grapes and ornamentals in this basin and elsewhere; citrus is very resistant to this kind of damage. Because little overt injury was seen on citrus but yields were continuing to decline, a unique, broadly based cooperative effort was begun in 1960 to find out if and, if so, how much actual injury was being caused by air pollutants.

Effective crop cooling of vineyards was obtained with the use of small amounts of water, intermittently applied through overhead sprinklers. The light sprinkling cooled the air, raised the humidity, and cooled the plants. Sprinklers functioning on 3-minute on and 15-minute off periods cooled the air by 7 to 10 degrees and raised the humidity 10 to 20 per cent. Plant temperatures were reduced 15 to 25 degrees. The cost of this operation was minimal. The true potential is still to be explored.

The availability of “clean” buds permitted limited observations on the effect of placing clean buds on infected under-stock. This was not part of the comparison above, however enough plants were budded to this combination to indicate the following effects of placing clean buds on infected stock: