296 ' STATE BOARD OF AGRICULTURE. 



Among the leading manufacturers of power outfits for potato and 

 vineyard outfits are E. C. Brown & Co., Kochester N. Y., and Wallace 

 Machinery Co., Champaign, 111. 



During the last year or two the entire crop in many of the large Michi- 

 gan vineyards was destroyed by the black rot of the grape and in many 

 the injury ranged from ten to seventy-five per cent. With a good outfit 

 'it is possible to spray an acre of grapes at an expense, for labor and 

 material, of not to exceed eighty cents per application. While under 

 the best of conditions this might not entirely prevent the rot in a vine- 

 yard where the loss would be fifty or more per cent if left unsprayed, 

 it would reduce it to such an extent that the loss would be hardly notice- 

 able, while a crop in which, fifty per cent of the grapes have been at- 

 tacked by the rot is practically destroyed. 



THE MILDEW OF THE GRAPE. 



Although its effects are seldom as noticeable as those of the black rot, 

 the downy mildew of the grape has for two or three years caused nearly 

 as much loss as the black rot. The injury from this disease is produced 

 fully as much upon the foliage as upon the fruit itself. It gives the 

 leaves a frosted appearance on the underside and the infected areas soon 

 turn yellow. If considerable portions of the surfaces of the leaves are 

 involved they will drop from the vines and as this often results in prac- 

 tically defoliating the vines, they are not able to ripen the fruit, which 

 remains in a green . or semi-ripe condition until destroyed by frosts. 

 Upon the fruit, it first has a greenish brown appearance and in severe 

 cases the fruit turns brown but does not afterwards blacken as in the 

 case of the black rot. 



The development of this disease is also influenced by the character of 

 the season, but unlike the black rot it flourishes when it is cold and wet. 

 Vineyards upon hillsides where the soil is well drained and of a sandy 

 loam nature are much less injured by this disease than upon low level 

 land, especially if it is poorly drained and the soil is heavy. This dis- 

 ease is one of the easiest to control by Bordeaux mixture. As a rule, 

 three or four applications are all that will be required. The first should 

 be given while the vines are dormant and the others at intervals of two 

 weeks, beginning as soon as the fruit is set. Vineyards treated in this 

 way will not only be free from mildew but the crop will ripen a week 

 to ten days earlier than upon unsprayed vines, even though the attack 

 is not severe enough to prevent the ripening of the fruit. By keeping 

 the vines in a healthy condition they will be able to complete their 

 growth and develop fruit buds for the crop .the coming year. 



