INSECTS AFFECTING PARK AND WOODLAND TREES 39 



This material has been found injurious to fruit buds of peach when apphed 

 in the fall, and it is very likely that it might kill the more tender buds of 

 some other trees when used in similar way. Karly spring- applications, how- 

 ever, do not affect buds of our fruit trees and this is probably true of orna- 

 mentals. This soap appears to be giving way to the more effective and 

 much cheaper lime-sulfur washes. 



The lime-sulfur wash, or as it is more generally known, the lime-sulfur- 

 salt wash is rapidly becoming a favorite remedy for scale insects in the 

 Eastern states. It may be prepared in a number of different wa)s with 

 very diverse proportions of the various ingredients, and still be effec- 

 tual. An old and very good formula consists of 40 lb lime, 20 lb sulfur 

 and 15 lb of ordinary salt to 60 gal. of water. Another calls for 15 lb 

 each of lime, salt and sulfur to 50 gal. water. Later experiments have 

 shown that these can probably be modified to considerable advantage and 

 the salt omitted. A very satisfactory combination is made by using 20 lb 

 lime and 15 lb sulfur to 50 gal. of water. The lime should be added to a 

 little hot water in a kettle, and as soon as slaking begins, put in the sulfur 

 and boil vigorously for at least 30 minutes, stirring constantly in order to 

 get a smooth mixture. Combination between the lime and sulfur is facili- 

 tated by the use of an alkali such as caustic soda, and recent experiments 

 have shown that sal soda, 10 lb to the above named amounts, makes a very 

 good wash and obviates the necessity of boiling. Several pails of hot water 

 are put into a barrel, the lime is added, quickly followed by the sulfur, then 

 the sal soda, and the entire mixture is stirred vigorously till the reaction 

 has ceased sufficiently so as to allow the covering of the barrel with burlap, 

 and the mixture is then allowed to stand for at least 30 minutes, strained 

 and diluted with cold water to the requisite amount. It is sometimes neces- 

 sary to add a little cold water to prevent the compound from boiling over 

 and care should be taken not to stir so much as to hinder the chemical reac- 

 tion. This latter formula, while very promising, is still in the experimental 

 stage. 



Fumigation. Scale insects can also be controlled very successfully by 



