APPLE DISEASES 47 
King are sometimes so grouped. A peculiar and interesting 
case was called to the authors’ attention in a New York State 
orchard where old trees of the Baldwin variety had been 
grafted to Twenty Ounce some twenty yearsago. The point of 
union is about midway distant between the crotch and the 
highest tip of the branches. The canker shows abundantly 
on the Twenty Ounce portions of the tree, but the Baldwin stock 
is entirely free from the disease. In most cases the disease 
extends down the Twenty Ounce bark to the point of union, 
there stopping very abruptly. This indicates that the Bald- 
win is at least not to be classed with the Twenty Ounce and 
others of the most susceptible kinds. In Ontario, Canada, 
Fic. 10. — Early stages in the development of black-rot of apple. 
the Ben Davis and Northern Spy are said to be susceptible 
varieties. 
Symptoms. 
Ripe fruits are more commonly attacked than green fruits. 
Signs of the disease may show anywhere on the surface or at the 
