DOSAGE SCHEDULES OF MORE IMPORTANT WRITERS. 



21 



crease in dimensions much more rapidly than in cubic contents is seldom taken 

 into consideration. The result is that the larger trees receive a relatively smaller 

 dosage than they should. 



Morse's schedule was prepared especially for the cottony cushion scale and probably 

 for the red scale. The schedules of Coquillett and Pease, and doubtless that of Craw, 

 were prepared for the red scale. Those of Johnson, Woodworth, the Riverside Com- 

 mission, and the Rural Californian were intended especially for use against the black 

 scale. The red scale was generally known to be harder to destroy than the black scale. 



In Morse's schedule all trees receive practically three-fourths ounce per 100 cubic 

 feet of inclosed tent space; in Coquillett 's, practically one-half ounce to 100 cubic 

 feet; in Woodworth 's schedule they receive one-third ounce for the same space. 

 In Cravv^'s table, the smallest tree receives approximately 9 times as great a dosage 

 rate as the largest; in Johnson's table, the smallest receives about 4^^ times the rate 

 of the largest; in that of the Riverside Commission, the smallest is allowed about 

 13 times that of the largest; in that of the Rural Californian, the smallest receives 

 about 8 times that of the largest; while in that of Pease, the smallest receives a dosage 

 rate about 14^ times as great as the largest tree. 



This short analysis seems sufficient to call attention to the irregularities of these 

 schedules. A study of the following table will reveal many other interesting points. 



Dosage schedules recommended by several recognized authorities, tvith computed dosage 

 rates per 100 cubic feet of space inclosed by tent. 



AMOUNT OF CYANID (OUNCES) PER TREE RECOMMENDED. 



a Bui. 71, Univ. of Cal. Agr. Exp. Sta. (1887). 



6 Insect Life (1889). 



c Destructive Insects (1891). 



dCal. State Bd. of Horticulture (1S96). 



cBul. 115, Univ. of Cal. Agr. Exp. Sta. (1896). 

 / Farmers' Bui. 127, U. S. Dept. Agric. 

 g From " Fumigation Methods," by W. G. Johnson. 

 h California Cultivator (1908). 



