i'KAK (WOWING IN CALIFORNIA. 373 



MEALY BUG (Pseudococcus sp.)- 



In a limited area bordering on the Sacramento River, near Courtland, 

 some species of mealy bug has for several seasons past been of consider- 

 able economic importance. This pest does its principal damage in the 

 calyx end of the pear. It enters the basin where feeding takes place, 

 with the result that the juices of the pear ooze out, forming a sticky 

 mass of gum. The egg masses are laid on the trunks and branches of 

 the trees. 1 



Control. 



Very successful control has been accomplished by means of miscible 

 oil sprays, Formula No. 7.* 



BEAN THRIPS (Heliothrips fasciatus). 



Late in the summer season pear growers frequently notice consider- 

 able injury from thrips. Generally the species present at this time is 

 the common bean thrips. This species is recognized by its black color 

 and white tips to the antennae and the white markings at the base of 

 wings. 



Control. 



Essig, in "Injurious and Beneficial Insects of California," recom- 

 mends the use of a formula prepared by J. R. Watson of the Florida 

 Agricultural Experiment Station, which is as follows : 



Commercial Lime Sulphur (33 Baum6) 5 gallons 



Black Leaf "40" 14 fluid ounces 



Water - 200 gallons 



Successful control may also be accomplished by the use of Formula 

 No. 3 or 11. 



BLACK SCALE (Saissetia oleae). 



Occasionally a bad infestation of black scale occurs on pear trees. 

 This pest is easily recognized by its characteristic black color and the 

 presence of an "H" shaped marking on the dorsal surface of the scale. 

 The young scales first feed upon the foliage of affected trees, later 

 detaching themselves and going to the branches. The winter season is 

 spent in a partially grown condition. 



Control. 



A dormant spray, using Formula No. 5, 6 or 7, applied any time 

 after the trees become dormant in the fall and before growth begins in 

 the spring will bring about effective control. 



BRANCH AND TWIG BORER (Polycaon confertus). 



This borer is widely distributed throughout the state but can not be 

 considered extremely serious. The adult is a small brown beetle which 

 lays its eggs on the twigs of various kinds of trees, including the pear. 



* Formulae for control on pages 183 to 188. 



'This species is apparently the same as the grape mealy bug, Pseudococcus bakeri. 



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