Page 26 



BETTER FRUIT 



March 



than a good brand of commercial arsen- 

 ate of lead. It is convenient to use, the 

 white paste having only to be mixed with 

 a small amount of cold water and added 

 to the spray tank containing the balance 

 of the cold water for dilution. 



There are many different brands upon 

 the market, and a number of them were 

 tested in spraying experiments in 1908. 

 In this comparative test each was used 

 at a strength of two pounds to 50 gal- 

 lons of water. Following is a list of the 

 brands tested and the manufacturing 

 companies furnishing them: 



Eagle — Adler Color and Chemical Works, 100 

 William Street, New York. 



Disparene — The Bowker Insecticide Company, 43 

 Chatham Street, Boston. 



Star — Fred L. Lavanberg, 100 William Street, 

 New York. 



Grasselli — Grasselli Chemical Company, Cleve- 

 land, Ohio. 



Rex — The Rex Company, Omaha, Nebraska. 



Target — American Horticultural Distributing 

 Company, Martinsburg, West Virginia. 



Swift's — Merrimac Chemical Company, 33 Broad 

 Street, Boston. 



Sherwin-Williams — Sherwin-Williams Company, 

 St. Louis. 



Samples were taken from each of the 

 above insecticides and submitted to the 

 Bureau of Chemistry of United States 

 Department of Agriculture for analysis. 

 Through the courtesy of J. K. Haywood, 

 chief of the miscellaneous division of 

 this bureau, the analysis of the samples 

 used by the writer is given in Table IX. 



In this connection it is interesting to 

 compare these analyses with what is 

 considered an arsenate of lead of proper 

 grade. Within the past year, at a con- 

 ference of state and government insecti- 

 cide chemists, entomologists and chem- 

 ists of insecticide manufactories, a stand- 

 ard for insecticides was established and 

 included in a proposed national insecti- 

 cide law. The requirements for com- 

 mercial arsenate of lead were as follows: 



An arsenate of lead shall be deemed adulterated: 

 first, if It contains more than 50 per cent of water; 

 second, if it contains total arsenic equivalent to less 

 than 12^2. per cent of arsenic oxide (Aso O3) ; third, 

 if it contains arsenic in water soluble forms equiva- 

 lent to more than 0.75 per cent of arsenic oxide 

 (As2 O5) ; fourth, if any substances have been 



Continued from I-'ebruary number 



TABLE VIII— COST OF SPRAYING INGRAM APPLES IN PLAT TWO 



First Second 



Spray Spray 



Gallons of spray per tree 4.74 3.67 



Cost of spray mixture per tree (cents) 4.90 2.20 



Cost of spray mixture per acre (dollars) 3.19 1.43 



Expense of applying mixture per tree (cents) 3.80 1.85 



Expense of applying mixture per acre (dollars) 2.51 1.20 



Combined cost of material and application per tree (cents) 8.76 4.05 



Combined cost of material and application per acre (dollars) .... 5.70 2.63 



Third 

 Spray 

 3.44 

 2.00 

 1.30 

 2.06 

 1.34 

 4.06 

 2.64 



AH 

 Sprays 

 11.85 

 9.10 

 5.92 

 7.77 

 5.05 

 16.87 

 10.97 



TABLE IX— ANALYSES OF ARSENATE OF LEAD 



Contents 

















Sherwin- 



Eagle 



Disparene 



Star 



Grasselli 



Rex 



Target 



Swift's 



Williatns 





41.36 



21.41 



48.34 



34.24 



35.75 



42.61 



41.03 



41.46 



Total lead oxide (PbO) 



37.79 



46.80 



36.88 



45.64 



44.64 



39.49 



38.46 



45.62 



Total arsenic oxide (As2 Or) . . . 



17.38 



22.11 



11.98 



16.90 



16.43 



14.44 



16.24 



6.03 



Water sokible impurities, exclu- 



















sive of PbO and AsoOg... 



0.76 



5.68 



1.04 



0.75 



0.67 



1.06 



1.45 



3.35 



Water of constitution and un de- 



















2.71 



4.00 



1.76 



2.47 



2.51 



2.40 



2.82 



3.54* 



Soluble lead oxide 



0.48 



0.67 



0.44 



0.58 



0.40 



0.32 



0.44 



1.61 



Soluble arsenic oxide 



0.82 



0.06 



0.04 



0.90 



0.87 



0.41 



0.71 



0.02 



*Also carbon dioxid. Lead carbonate 



is present 



in the mixture. 











TABLE X— ARSENATE OF LEAD AND PARIS GREEN 

 For dates and number of times sprayed, see Table I, printed in February number 



Apples Counted: 



Windfalls — Per cent idtli : 



Codling moth worm holes 



Curculio crescents or codling moth worm holes 



"Specks" from curculio or codling moth 



Cither chewing insect injuries 



Spray burn at calyx 



Picked Fruit — Per cant with: 



Curculio crescents 



(.[odling moth worm holes ' 



Curculio crescents or codling moth v,'orm holes 



"Specks" from curculio or codling moth 



C)ther chewing insect injuries. 



.Spray burn at calyx 



Both Vl'indfalls and Picked Fruit — Per cent free from 



Curculio crescents 



Codling moth worm holes 



Curculio cresceiits or codling moth worm holes 



"Specks" from curculio or codling moth 



Other chewing insect injuries 



Spray burn at calyx 



Formulas used: Paris green, 

 pounds to 50 gallons of water. 



Plat 6 



Plat 5 



Plat 4 



Check 



Paris 



Arsenate 



Not Sprayed 



Green 



of Lead 



. 4534 



4544 



6442 



2065 



1143 



1705 



2469 



3401 



4737 



. 18.74 



3.94 



3.17 



7.89 



.09 



.18 



25.61 



4.02 



3.34 



7.02 



.96 



1.58 



. 29.73 



16.88 



15.01 



0.00 



17.41 



1.64 



. 45.50 



7.67 



3.80 



. 14.90 



.47 



.03 



53.90 



7.99 



3.90 



3.20 



1.67 



1.50 



3.07 



3.20 



3.50 



0.00 



23.46 



1.40 



. 66.66 



93.27 



90.37 



. 88.29 



99.63 



99.75 



58.94 



93.00 



96.18 



. 95.02 



98.50 



98.43 



. 84.79 



93.35 



93.40 



. 100.00 



78.81 



98.58 



6 ounces: lime, 4-0 pounds; water, 50 gallons. Arsenate of lead, V/2 



MAMMOTH B C Kl ! 1-: \U<\ 



MR. E. F. BENSON 

 Presiding officer of recent Washington State 

 Horticultural Society Meeting 

 Prosser, Washington 



mixed and packed with it so as to reduce, lower or 

 injuriously affect its quality or strength; provided, 

 however, that extra water can be added to lead 

 arsenate (as described in this paragraph) if the 

 resulting mixture is labeled lead arsenate and 

 water, the percentage of extra water being labeled 

 and correctly stated on the label. 



Since the arsenate of lead is sold by 

 weight, usually as a paste, the strength 

 of the product may be reduced by manu- 

 facturers by the addition of water. Fruit 

 growers should, therefore, bear this fact 

 in mind. The table shows all samples 

 within this standard indicated in respect 

 to moisture, but a comparison of the 

 moisture contents of the samples ana- 

 lyzed should not be considered, since 

 the arsenates before the samples were 

 taken were known to have suffered in 

 loss of moisture by evaporation or leak- 

 age in varying amounts, owing to the 

 different kinds of containers in which 

 they were received. The content of 

 arsenious oxide, it will be seen, varied 

 for six of the eight samples from 14.14% 

 to 22.11%. Only two samples of the 

 eight examined were below the standard 

 for arsenious oxide. Sample No. 64.53 

 was but slightly deficient in arsenious 

 oxide, while No. 64.58 was greatly defi- 

 cient in this respect, showing only 6.03%. 

 Since the soluble arsenic oxide is con- 

 sidered the projierty likely to burn the 

 fruit or foliage, a 

 minimum amount in 

 arsenates of lead is 

 desirable. In no case 

 did the amount equal 

 1%, and in some the 

 analysis showed a 

 remarkably low per- 

 centage. Practically 

 no injury followed 

 the use of any. 



Quotations of the 

 price of the different 

 kinds of arsenate of 



