o22, REPORT OF THE BOTANICAL DEPARTMENT OF THE 
a later publication* he holds that the dying of cherry trees 
in the Rhine districts, so elaborately discussed by Frank and 
others and attributed to Valsa leucostoma, is primarily due to 
the above type of winter-injury. Sometimes many branches 
or even whole trees die. The bark and wood of the affected 
trees had the browned appearance typical of frost-injury. 
Anderhold and Wehmer are said to have shown that Valsa 
leucostoma is only a wound parasite and may only vegetate on 
much-weakened trees, and later Ltistner is said to have shown 
that it would only attack practically dead parts of cherry 
trees. It is therefore thought that the planting of frost-resist- 
ant varieties is more important than the careful destruction 
of the fungus-infected dead twigs. Sweet cherry is often simi- 
larly affected in this country. Some such cases became evident 
late this summer in an orchard of this Station. Several large 
trees died from the top downward. , 
Sour-cherry trees were affected again, this autumn, in the 
manner described in 1899 by F. C. Stewart,* of this Station, 
under the head of ‘ Leaf scorch of cherry.” The affected 
branches are usually lateral, and seem generally to have dis- 
colored wood, as observed by Stewart. Later he reported*® 
that though the “season of 1900 was drier than that of 1899, 
there was none of the cherry-leaf scorch such as occurred in 
1899.” In 1900 branches on the leaf-scorched trees were found 
injured, many buds dead, and the remaining fruit-pedicels were 
unusually short. Probably Sorauer’s experiments and obser- 
vations mentioned above sufficiently account for the primary 
cause of these cases of suddenly drying normal leaves. But 
as in all types of winter-injury, in which trees are not killed 
outright, the availability of water may determine the time 
at which the injury becomes apparent, so in these cases the 
drought of late summer marked the branches most frost-injured 
by drying their leaves. 



“ Pflanzenkrankheiten, I, p. 553. 1909. 
*N. Y. Agrl. Expt. Sta. Bul. 162, pp. 171-176. 1899. 
“N.Y. Agrl. Expt. Sta. Bul. 191, pp. 309-16. 1900. 
