124 



INJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA. 



about 1-25 inch long. They are massed in large colonies at the base 

 of the u ii folding leaves (Fig. 105), where they are thoroughly pro- 

 tected from ordinary measures of control. 



Life History. — Very little of the true life history of this coccid is 

 known, excepl thai it is a very troublesome pest to the date palm. The 

 females give birth to living young, 

 which appear in great numbers in the 

 early spring. These seek the base of 

 the palm leaves, where they are 

 thoroughly protected Gradually the 

 logs disappear and white wax is 

 secreted to cover and protect the 

 naked body. The male is unknown. 

 The prolificacy of this species is a pro- 

 Dounced characteristic. 



Nature of Work. — As above stated, 

 the females congregate in large 

 colonies at the bases of the tender 

 unfolding leaves, which are often de- 

 formed and so injured as to greatly 

 hinder growth. 



Distribution.— The Marlatt scale is 

 limited in the southern part of the 

 State to Riverside and Imperial coun- 

 ties, where dates are commercially 

 ill-own. 



Food Plant. — All stages feed at 

 the base of the leaves of the com- 

 mercial date palm. 



Control. — Carbolic acid emulsion 

 poured in large quantities at the 

 bases of the leaves until the trunk is 

 thoroughly saturated has given very 

 good results, according to former 

 County Horticultural Commissioner 



W. H. Wilsie Of Imperial County. Fig. 105. — The Marlatt scale, Phoeni- 



"D-~£~ ~~ "D tt tti„™u~ ,£ 4-u ~ \ — ■: cococcus marietta Ckll. Immature fe- 



ProteSSOr R, II. Forbes ot the An- males feeding on the opening leaves. 



zona Agricultural Experiment Station Natural size. Collected in Imperial 



, , ' . . , , County by Geo. P. Weldon. (Original) 



reports to have controlled the pest by 



burning over the palms with a gasoline torch. 77 At a special meeting 

 of the California date growers in Los Angeles, November 9th. Mr. 

 Bruce Drummpnd of the United States Department of Agriculture 

 stated tli.it by far the best remedy for controlling the Marlatt and 

 date palm scales on the old palms, and especially the offshoots, is a 

 spray composed of the following: liquor cresolis compositus 49 per 

 cent, 1 quart and distillate (about 32 degrees), 4 cpiarts. These are 

 thoroughly mixed to form a stock solution and diluted 1 part to 50 

 parts of water for use. The offshoots are completely immersed for 

 some minutes. This mixture should be used within six hours after 

 preparation, as it soon deteriorates. 



'•Jr. Ec. Ent. VI, pp. 415-416, 1913. 



