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Of 78 compounds screened in laboratory investigation to determine the effectiveness of sorptive dusts for killing and controlling cockroches, two compounds, a silica aerogel designated as SG 67–Dri-Die 67–and a silica gel called SG 77 were outstandingly effective.

Experimental applications of ferric sulfate to nonsaline alkali spots in rice fields have greatly increased yields.

Stunted and yellowed Brussels sprouts were observed in many fields in San Mateo County in 1957. The affected plants grew very slowly after transplanting and interveinal yellowing or chlorosis developed shortly. As the plants developed, the older leaves cupped upward and developed small, necrotic spots near the margins. The plants seemed more severely affected while they were young, but tended to outgrow the trouble after a few months. The yields were drastically reduced and maturity was delayed.

That the micronutrient nutrition of citrus trees may be changed by continued heavy applications of commercial fertilizers has been indicated by several reports. However, there is very little available experimental evidence from field studies on the influence of soil applications of phosphate, potash, and dolomite fertilizers on the micronutrient concentration in Valencia orange leaves.

The following article is the second of two reports on Quality Studies with Strawberries. The first report appeared in the January issue.

Erratic results obtained in organized ponderosa pine planting programs– some successful, more not successful– emphasized the need for reliable planting systems applicable to California conditions.

Damage to apricots by mealybugs is a relatively new problem as it was not reported prior to 1956. The species involved has been identified as the grape mealybug–Pseudococcus maritimus (Ehr.) –a common pest of grapes and pears.

One of the more promising of the newer herbicides for weed control in commercial flower crops is neburon– l-n-butyl-3 (3.4-dichlorophenyl)-1-methylurea–a chemical low in water solubility and toxicity to man or animals.