THE MONTHLY BULLETIN. 293 



CITRUS FRUIT INSECTS. 



The Citrus Red Spider. 



The red spiders are especially destructive to the citrus. Like the 

 two-spotted mites, they are very minute and have eight legs when 

 adult. They are generallj^ reddish in color. They feed principally 

 on the undersides of the leaves and are more abundant on the interior 

 foliage of the tree. The infested leaves have a yellow, spotted appear- 

 ance. Dusting the trees with flowers of sulphur on a night when dew 

 is plentiful and followed by hot days, has produced fine results, 

 according to J. A. Prizer, of the San Diego Fruit Company. Lime- 

 sulphur solution, 2 per cent to 2^ per cent strength, applied at a pres- 

 sure of from 150 to 200 pounds, is generally used if unfavorable 

 conditions exist for the dry sulphuring. Atomic sulphur, six to seven 

 and one half pounds to 100 gallons of of water, is less likely to burn 

 the leaves than the lime-sulphur solution. Spray when the mites 

 become numerous enough to produce injury. In very hot weather it 

 is not advisable to spray unless the situation demands it. 



The Soft Gray Scale. 



In certain parts of the State the soft gray scale is doing considerable 

 damage to the citrus. The scale differs from the soft brown in that it 

 is more gray in color, less shiny, the young appear to be more flattened 

 and more transparent. As the scale has been little affected by fumi- 

 gation at the time the best results are obtained in fumigating for the 

 black scale, it seems neccessary to make a separate fumigation for this 

 pest. J\lr. Delacourt Kell, county horticultural inspector of the 

 Pomona and Claremont district, has found that the best time to fumigate 

 is from July 20th to the end of August, using a three fourtlis schedule. 

 At this time of the year the scales are in the right stage for fumigating 

 with cyanide. Do not fumigate at a temperature of 70° Fahr. or above. 



MISCELLANEOUS INSECTS. 



The Hop Aphis. 



The hop aphis is a pale, yellowish-green member of the destructive 

 plant louse family. W. B. Parker states in Bulletin 111, Bureau of 

 Entomology, Department of Agriculture, that the hop aphis injures 

 the hop crop in two ways: By furnishing a medium (honey-dew) for 

 the black smut fungus to grow in, and by sucking out the juices of 

 the plant. The cone scales covered with the honey-dew secreted by 

 the hop aphis are soon covered with the black smut fungus, thus lower- 

 ing the commercial value of the hops. The aphids stunt the plant to 

 a greater or less extent, depending upon the seriousness of the infesta- 

 tion. The formula consisting of blaek-leaf 40, one to 2000 of water 

 (6| ounces to 100 gallons) with a spreader, consisting of either soap, 

 about four pounds to 100 gallons of mixture, or flour paste, four pounds 

 to each 100 gallons of the mixture, is recommended. The plant lice must 

 be hit by the spray in order to be destroyed. 



