258 



AMERICAN VINES. 



Coniothyrium diplodiella, or white rot, grows sometimes 

 on the young shoots and kills them. It is easily treated 

 with Bordeaux mixture. 



Pourridie (Fig. 141) causes great damage in nurseries. 

 Up to the present there is no real remedy. As soon as detected 

 in a nursery, it is best to discontinue planting in that spot 

 for two or three years. 



Mildew is also serious, as it causes the leaves to fall pre- 

 maturely, and stops the growth of the plant, the formation 

 of knitting tissue, the maturing of the shoots, and the develop- 

 ment of roots. As the tender shoots of the young plant are 

 very sensitive to its action, Bordeaux mixture should be used 

 frequently (six or eight times during the summer). 



Fibrillaria (Psctthyrella ampelina) grows sometimes be- 

 tween the surfaces of the sections at the joint, in the form 

 of a thick white coat, thus preventing the 

 healing tissue of the scion reaching the stock, 

 and vice versa. Its damages are not very 

 considerable. It is easily checked by 

 watering the stock with a 10 per cent, solu- 

 tion of sulphate of iron. 



Sderotinia Fuckeliana (Fig. 142), or Bot- 

 rytis cinerea, does a little harm to the 

 grafted cuttings when stratified in wet sand. 

 To avoid this it is only necessary to use dry 

 sand for stratification. The Scl. Fuckeliana 

 forms at the level of the tongues and 

 clefts, hard black warty nodules, about 

 one-eighth of an inch thick. They are 

 wedge-shaped, and by their intrusion be- 

 tween the joints prevent the latter adher- 

 ing to each other. The surfaces become 

 dry, and the formation of knitting tissue 

 prevented. The grafting stock may form 

 roots in the nursery, but the scion soon 

 becomes dry. 



The Botrytis cinerea sometimes attacks branches pre- 

 served in too damp soil. Its mycelium pentrates their tissues 

 and kills them. 



Fig. 142. 

 Botrytis Cinerea. 



