U. S. EXPERIMENT STATION BULLETINS. 423 



surface. The grape may also develop unequally, the affected side being 

 flattened. 



This form of rot is not characterized by a softening of the tissues, as in 

 the case with others we have mentioned. The tissues slowly collapse, but 

 at the same time become hard and wrinkled. 



Believing that the foregoing remarks will, after a little study, enable 

 anyone to recognize these various diseases, we will next direct our atten- 

 tion to the remedies and their preparation. 



KEMEDIES AND THEIR PREPARATION. 



Experience has shown that for all practical purposes there are but four 

 fungicides worthy of consideration in this connection: (1) The simple 

 solution of copper sulphate: (2) the Bordeaux mixture; (3) the ammoni- 

 acal solution of copper carbonate: and (4) eau celeste. Of course there 

 are other preparations which bid fair to be fully as valuable as any of the 

 preceding, but as yet we do not know enough about them to recommend 

 their extended use unqualifiedly. 



1. Simple solution of copper sulphate. — This is prepared in the usual 

 way by simply dissolving 1 pound of the copper sulphate in 25 gallons of 

 water. 



2. Bordeaux mixture. — The only formula now generally used is that 

 containing 6 pounds of copper suljliate and 4 pounds of lime to 22 gal- 

 lons of water. For many reasons wc find it advantageous to use powdered 

 copper; still, when time is not an important element, the crystals answer 

 just as well and, as a rule, are from 2 to 3 cents cheaper per pound. In 

 our work we usually provide ourselves with three barrels, one of which we 

 divide in the middle, making two tubs holding 22 gallons. One of the 

 barrels we use for water, which is obtained at the nearest well, clear 

 stream, or pond. Twelve pounds of copper sulphate are weighed out and 

 placed in one of the tubs, 6 or 7 gallons of water are added and the cop- 

 per stirred in this until the water is blue. This blue solution is then 

 poured into the empty barrel and 6 or 7 gallons more of water are poured 

 into the tub containing the copper and the latter is stirred as before. 

 This process is repeated until all of the copper is dissolved, it being found 

 that 16 or 20 gallons of water are necessary for this purpose, providing 

 crystals are used and the water is cold. Powdered copper sulphate 

 requires much less labor and water to dissolve it, and for this reason we 

 prefer it to the crystals. All of the copper being dissolved, 8 pounds of 

 lime are slaked in one of the tubs. After slaking, enough water is 

 added to make a rather thin whitewash, then this is poured slowly into the 

 barrel containing the copper solution. We usually strain the whitewash 

 through a coarse gunny sack, having the latter stretched over the head of 

 the barrel. The straining removes all of the small pieces of lime, sticks, 

 straws, etc., which have a tendency to clog the nozzle. After pouring in 

 all the whitewash, more water is added until the barrel is filled to within 

 5 inches of the top. The solution is then thoroughly stirred, when it is 

 ready for use. 



Of course, the above process can be variously modified as occasion may 

 require. Instead of hauling the water to the vineyard it may be found 

 more convenient to prepare the mixture near the water supply and then 

 convey it where it is to be used either in barrels or tanks made for the 

 purpose. 



