12 AMERICAN VINES. 



Many of these failures were attributed to the action of 

 the phylloxera. No doubt many of the American varie- 

 ties cultivated had only a slight degree of resistance; 

 but, with the greater number, the failures (and this has 

 since been proved) were due only to their poor adaptation 

 to the soil. Without doubt, the first quality required 

 for a grafting stock, or even direct producer, is a high 

 degree of resistance to phylloxera; this is a guarantee to 

 its long duration in suitable soils. To make use of 

 varities of small or even medium resistance is to court 

 certain failure. However, it is none the less true that in 

 some cases the phylloxera resistance is helped by growth 

 in a thoroughly suitable soil. 



It would be easy to cite numerous examples to prove 

 this assertion. One of the clearest cases is offered by the 

 old collections at the School of Agriculture, Montpellier. In 

 a bad place, closely planted side by side, with interlacing 

 roots, are Rupestris, Solonis, Cornucopia, and a number of 

 other varieties. The Rupestris has only a few small 

 nodosities at the extremity of the rootlets and no tuber- 

 osities, or very few, and its resistance may be expressed as 

 1 8 the maximum, or absolute indemnity, being 20. The 

 Solonis, besides a great number of nodosities, bears, on the 

 roots or secondary structures of the year or older, a few 

 small hardly prominent tuberosities, the alteration of which 

 rarely reaches the main roots; its resistance is expressed 

 fairly accurately as 15 The roots of the Cornucopia are, 

 on the contrary, covered with very large nodosities and 

 very prominent tuberosities] and its resistance may be 

 given as 4. 



These three varieties have been planted for twenty-one 

 years. If the phylloxera had been the only factor concerned 

 in the development of their exterior vegetation, it would be 

 in the proportion of 18, 15, 4. The results are just the 

 contrary. The Rupestris, on which the phylloxera has 

 hardly any effect, is stunted, nearly dying, and its exterior 

 vegetation is equal to 2, the maximum being taken as 20. 

 The Solonis, although but slightly affected by the phylloxera, 

 is also stunted, though not so badly as the preceding; its 

 development may be expressed as 4. The Cornucopia, on 

 the contrary, although much attacked by phylloxera, has 

 a great vigour and vegetation, that may be exactly ex- 

 pressed as 1 6. Thus the phylloxera had. after all, but 

 little effect. 



