"Whale-oil soap. — For vines in foliage, whale-oil soap is used at the 

 rate of 1 pound to 8 or 10 gallons of water. There are several grades 

 of this article on the market, but a potash whale-oil soap is best, 

 especially one that does not contain more than 30 per cent of water. 



Kerosene emulsion. — This doubtless will be equally satisfactory as a 

 spray against the grape leaf-hopper, and may be prepared as follows: 



Whale-oil or other soap pounds. . 2^ 



Kerosene ( 150 flash test) gallons . . 5 



Water to make do 50 



The soap is dissolved in 6 to 8 gallons of hot water, and the kerosene 

 is at once added. The whole is then thoroughly emulsified by the 

 use of a hand pump, pumping the liquid back upon itself for 8 or 10 

 minutes or until a creamy- white emulsion results. This, when diluted 

 with the required amount of water, will contain 10 per cent of kero- 

 sene, which strength should be effective in destroying young hoppers 

 without injuring the foliage or the fruit. If a smaller quantity of 

 emulsion than 50 gallons is desired, it may be made, simply observing 

 the proportions given. 



FUNGOUS DISEASES. 



The fungous parasites of the American varieties of grape are indig- 

 enous, and came originally from the native wild vines. With the 

 gradual extension and development of the grape-growing industry 

 there has also been an increase in the distribution and destructiveness 

 of these fungous diseases. The conditions which necessarily obtain 

 in commercial grape culture have disturbed the equilibrium which 

 had become established between the vine and its parasites in their wild 

 state, and have facilitated the production and distribution of the dis- 

 eases. In the selection and breeding of the grape attention has been 

 devoted chiefly to the improvement of the fruit, and this has appar- 

 ently resulted in a decrease of the natural powers of resistance to 

 disease originally possessed by the wild vines. 



In certain sections of the country where grape growing was once a 

 profitable industry it has largely been abandoned, chiefly on account 

 of the great loss caused by disease. The amount of loss from fungous 

 diseases of the grape in the eastern half of the United States during 

 the past season (1906) is estimated at from 15 to 20 per cent of the 

 entire crop. In some localities it reached 40 to 50 per cent, and in 

 some particular vineyards where there was promise of a crop of 4 or 5 

 tons per acre the loss was total, while in one favored region the loss 

 was not over 5 per cent. 



Injury due to fungi depends largely upon weather conditions. The 

 conditions most favorable for the development of the majority of the 

 fungous diseases are excessive moisture and heat. The general 

 physiological condition of the vines is also important. Vines which 

 are kept thrifty and vigorous by proper care and cultivation are not 



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