MICHIGAN EXPERIMENT STATION BULLETINS 329- 



it should be applied before the leaves have closed over the insects. The 

 decoction can be made by soaking a half bushel of tobacco stems in a 

 barrel of water for five or six hours. If wanted for use immediately 

 the water should be hot. The stems can be used for several barrels of 

 water, the color and odor of the water indicating when they have been 

 exhausted. 



POTASH LYE. 



For spraying trees while dormant to destroy insects, fungi, and secure 

 a smooth bark, use 



Black potash 2 pounds 



(or concentrated lye 1^ " ) 



Water 5 gallons 



Care should be taken in preparing and applying this solution as it is 

 very caustic. It can only be used while the trees are dormant. 



The addition of one pound of lime and an ounce of Paris green to the 

 above makes it especially valuable for the trunks of trees to keep away 

 borers. 



WHALE OIL SOAP. 



For all classes of insects, and particularly for those that suck the sap, 

 whale oil soap, made from fish oil and potash, is an excellent remedy. 

 Among the best brands are those manufactured by James Good, Hurst 

 St., Philadelphia, who sells his Potash No. 3, at three and one half cents- 

 per pound in barrel lots, and from five to ten cents in smaller quanti- 

 ties. The Anchor brand of Leggett and Brother, 301 Pearl St., New York, 

 is sold at four cents per pound by the barrel, or at six and one half cent& 

 per pound for fifty pounds. Both are reliable brands. 



For scale insects it should be as strong as one or even two pounds to 

 the gallon of water, to be applied hot while the trees are dormant. After 

 growth starts the amount of water should be increased to five gallons to- 

 a pound of the soap. Whale oil soap may be used in making kerosene 

 emulsion. 



FUNGICIDES. 



As noted above the use of the fungicides is to cover the plants and to- 

 destroy the spores of fungi which fall upon them. For this purpose 

 Bordeaux mixture is most valuable. 



BORDEAUX MIXTURE. 



Copper sulphate (granulated) 4 pounds 



Lime (fresh) 4 " 



Water 40 gallons 



The above is known as the 'one to ten' formula and may be slightly 



modified without destroying its efiiciency. When preparing Bordeaux 



mixture it is advisable to first make a stock solution that can be mixed' 



and used as desired. Take twenty-five pounds of copper sulphate and 



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