4^6 Circular No. 2. 



Bordeaux Injury. 



Some plants are injured by the ordinary strength ot Bordeaux even when prop- 

 erly made. Others like the apple are sometimes injured by quite weak Bordeaux 

 under certain weather conditions. The leaves of most varieties of stone fruits, 

 especially peaches, and Japanese plums are almost sure to be injured by Bordeaux 

 except in very weak mixtures. The injury to these plants consists usually of small 

 holes in the leaves, very similar in appearance to the shot hole efifect of certain 

 fungi. The injury on the apple occurs on both the leaves and the fruit. On the 

 leaves it consists of quite definite brown spots very much like certain leaf spots 

 due to fungi. Where the injury is quite severe the affected leaves turn yellow and 

 fall. The injury on the fruit takes the form of russeting. It may even cause large 

 cracks to appear. Some varieties of apples suffer more than others. Wet weather 

 during the spraying season appears to be one of the chief factors in the production 

 of Bordeaux injury, on apples. It has also been shown that "the more copper 

 sulfate, the greater the injury." It is to be understood, however, that injury 

 from Bordeaux is much less common and serious than injury from the scab, to pre- 

 vent which it is applied. For fuller discussion of this subject see the N. Y. (Geneva) 

 Bull. 287. 



Good nozzles {hole 1-16 in.), good pressure (100 to 140 lbs.) and a good man, make 

 spraying pay. Tlioroughness is the secret of successful spraying. Be thorough. 



Soda Bordeaux. 



Soda (Commercial lye), about i J lbs. (acc'd to strength) 



Copper sulfate 5 lbs. 



Lime, about ^ lb. 



Water 50 gals. 



Dissolve the copper sulfate in 30 gallons water; dissolve the lye in a gallon or so 

 of hot water, dilute to 15 gallons and pour slowly into the copper sulfate solution. 

 Add milk of lime to test with litmus or ferro-cyanide and add water to make 50 

 gallons. This mixture is rather difficult to prepare as there must be neither an 

 excess of copper sulfate or of the lye. The lye must be of such strength that i h lbs. 

 will not quite neutralize the 5 lbs. of copper .sulfate. The small amount of lime is 

 added to completely neutralize the copper sulfate. It is a colorless mixture and 

 desirable as it will not clog nozzles. Should be used witli caution for unless prop- 

 erly made will injure foliage severely. See N. J. Bulls. 167 and 194. 



Ammoniacal Copper Carbonate. 



5-3-45- 



Copper carbonate 5 oz. 



Ammonia (26° Beaumc) 3 pts. 



Water 45 gals. 



Make a paste of the copper carbonate with a little water. Dilute the ammonia 

 in seven or eight quarts of water. Add the paste to the diluted ammonia and stir 

 until dissolved. Add enough water to make 45 gallons. Allow it to settle and use 

 only the clear blue liquid. This mixture loses strength on standing. Used in 

 place of the Bordeaux where one wishes to avoid staining maturing fruits or orna- 

 mental plants. Not considered to be as effective as the Bordeaux. 



