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planted, generally succumb with Form II, if not perfectly hardy. 

 Some Viniferas develop this form more rapidly on the moister 

 soils, which favor a rank growth (Tokay), others on the poorer 

 and 'drier soils, on which the growth becomes impoverished. 



Form III. In this form the disease enters the top of the 

 vine from the root, which almost always seems to occur while 

 the growth of the vine is rapid and exposed to great heat and a 

 dry atmosphere and transpiration through the foliage therefore 

 excessive. Vines which are not exceedingly vigorous, may also 

 show this form, but such vines always attained their full size before 

 the disease entered the tissue of their wood, which enabled them 

 to go through Form II without being killed. In grafting Lenoir, 

 Cordifolia, Candicans and ojthers, which have been considered re- 

 sistants unconditionally, ,on Riparia, having the disease as Form I, 

 and irrigating heavily, so vines make rapid growth, while the heat 

 is great, the grafts will readily develop Fprm III of the disease. 

 Similar cases can be seen also in the field sometimes; vines having 

 shown great vigor, rapidly develop Form III from Form I. The 

 characteristic symptoms of Form III have so often been described 

 as the only symptoms of the disease, as immature wood on the 

 canes, especially the tips, short growth, failure of fruit to mature 

 and spots on the leaves, that it is not necessary to dwell on this 

 point. Rupestris St. George vines favor an acute development of 

 the disease mpre on the richer or moister soils and Lenoir and 

 Champini vines more on the poorer or drier. The above three 

 forms are simply different stages in the development of the disease 

 and lines of demarkation are not always plain. Whenever the disease 

 makes its presence known as Form III, we may be sure, that 

 most of the vines in the vineyard, however thrifty they may be, 

 have the disease as Form I, and a good many as 

 Form II. As I have recommended topping vines as a pre- 

 ventive of the disease, I must say at the present time, 

 that, while it seems to prevent Form III somewhat, it apparently 

 increases the chances of the disease as Form II. But if practiced 

 lightly in checking the growth of running canes by pinching, I 

 believe it has a good effect. 



I have never seen an American vine on its own root in this 

 locality show Form III of the disease, but at its worst only the 

 beginning of Form II, which manifests itself with these vines in a 

 slight unthriftiness and by no other signs. Whenever a vine 

 shows unthriftiness, we < must conclude, that this disease, if not the 



