170 PLUM. 



recommend " Paris-green paste in the proportion of 1 oz. to 

 8 or 10 gallons of water for Plums ; and 1 oz. to 20 gallons 

 of water for Apples." Apple leafage was found to be more 

 tender than that of Plums. Pear leafage should be treated 

 like that of Apple. 



For Currants the strength found safe was the same as 

 for Plums — 1 oz. of " green " to 10 gallons of water ; but as 

 the foliage grew stronger, 1 oz. to 8 gallons of water was 

 found not too strong. Neither of these strengths of mixture 

 damaged the leafage, but they killed the caterpillar. 



These jwo^^ortions should not he exceeded. In some instances 

 greater strength has been used without bad effects on the 

 leafage ; but this was certainly attributable, in one case, to 

 heavy rain following the over-application, and probably, if 

 details were procurable, non-injury from over-strength could 

 be traced to casual coincidence in other cases also. 



Capt. Corbett, the Superintendent of the Toddington Fruit- 

 grounds, writing to me on the 3rd of July, and mentioning 

 his satisfaction with the results of spraying, also noted, "The 

 proportions I fixed upon after the first trials, viz. 1 oz. to 

 10 gallons of water for Plums, and 1 oz. to 20 gallons of 

 water for Apj^les, must not be exceeded." 



To the above, Mr. Masters, Secretary of the Experimental 

 Committee, added a further note, with the following informa- 

 tion and useful hint regarding mixture of flour with the green : — 



"When the foliage of trees is young and tender, I do not 

 think it safe to apply the Paris-green stronger than in the 

 proportion of 1 oz. to 10 gallons of water. But when the 

 foliage is matured, and the caterpillar is full grown, a solution 

 of 1 oz. of Paris-green to 6 gallons of water may be safely 

 used ; for every case it would be well to use about 2 lb. of 

 fine wheat flour to every pound of Paris-green; it thickens 

 the solution, and prevents the particles of Paris-green from 

 settling at the bottom of the vessel, and, when it is spra3''ed, 

 helps to secrete the preparation on the foliage." 



One point of difficulty which occurred in the experiments 

 and needs care in regular work is the risk of hot bright 

 sunshine occurring after spraying and causing mischief to 

 the leafage, this especially where the right strength has been 

 exceeded, or the spray not rightly delivered at the leafage, but 

 so that it remained in excessive quantity.* 



* In Bulletin No. 36 of the Agricultural Experiment Station of Missouri, 

 1896, on remedial measures to destroy two kinds of leaf caterpillars, it is 

 mentioned that those of the small moth Tcras minuia may be destroyed by 

 spraying with the following mixture : Paris-green, 1 lb. ; fresh lime, 3 lb. ; 

 water, 150 gallons ; and it is especially observed : — " Never omit the fresh 

 lime ; always use as much fresh lime by weight as Taris-green. This will 

 lessen the chances of burning the leaves by repeated sprayings." — J. M. Sted- 

 man, Entomologist ; October, 1898. 



