120 



MANUAL OF MODERN VITICULTURE. 



Fig. 102. White mycelium 

 of Dematophom necatrix 

 developed on dead vine. 



vines, and the water allowed to run in the channels formed 

 between the rows (Fig. 101). Watering should be done as 

 seldom as possible with the minimum quantity of water 

 required. An excess of water some- 

 times prevents knitting, and the cooling 

 of the soil results in some cases in 

 plants which, although well developed, 

 have loose spongy tissues rendering 

 them weak. Finally, under certain cir- 

 cumstances it favours the development 

 of Dematophora necatrix, the most 

 dangerous of fungoid diseases. (Fig. 

 102.) It is preferable to water as late 

 as possible to allow the soil to get 

 warm, which promotes root growth, 

 but this is more particularly useful 

 with grafted cuttings which have to 

 knit at the same time. The soil should 

 always be loosened after watering to 

 prevent it from caking. One should also frequently examine 

 the grafts and sever the young roots which develop very 

 easily in the nursery. 



Nurseries must be carefully protected against mildew 

 on account of the great facility with which the young roots 

 are attacked by this fungus, and of the serious results from 

 the defective lignificatiou caused by it. Notwithstanding 

 the exceptional care which grafted cuttings necessitate, and 

 the smaller percentage of strikes as compared with grafts 

 made on rooted sto -k, they present certain advantages which 

 will always give them a predominant place in reconstitution. 

 They can be made indoors during the winter, preserved by 

 stratification until the planting season, and vine-growers are 

 enabled to have grafted rootlings after a year in the nursery, 

 and after a few weeks only when frames are used. The 

 improvements made in grafting machines, giving better 

 results, and the decrease in the price of American cuttings, 

 add increased importance to this method of propagation. 



The preservation of grafted cuttings by stratification re- 

 quires certain care. If the sand is too damp the sclerotia 

 of a fungus known as the Sclerotinia Fuckdiana develops, 

 sometimes inside the cleft of the graft, preventing knitting 

 (Fig. 103). Under these circumstances stratification of 

 grafted cuttings in damp moss was tried as an alternative. 

 Those who used it were unanimous in recommending it. 



