54 Trans. Acad. Sci. of St. Louis. 
leaf injury. Osage orange showed the least effect of any 
of the broad leaved trees. : 
Conifers as a class were much less affected than were 
the broad leaved trees. Scotch pine suffered most, but 
even in the worst cases lost only a few leaves and showed 
few wounds on the bark. Austrian pine was still less 
affected than Scotch pine and red cedar showed no in- 
jury. 
The relative resistance of the broad leaved species in 
this storm is shown in the following table in which the 
worst affected species are placed at the head of the table. 
DEFOLIATION. INJURY TO TWIGS. 
- Catalpa (Catalpa). Catalpa. 
Sycamore (Platanus). Russian Mulberry. 
Russian Mulberry (Morus). Box Elder. 
Cottonwood (Populus). Cottonwood. 
Box Elder (Negundo). White Willow. 
Black Walnut (Juglans). Sandbar Willow. 
Green Ash (Fraxinus). Sycamore. 
Silver Maple (Acer). Green Ash. 
Honey Locust (Gleditschia). Silver Maple. 
White Willow (Salix). Black Walnut. 
Sandbar Willow (Saliz). Honey Locust. 
American Elm (Ulmus). American Elm. 
English Elm (Ulmus). English Elm. 
Osage Orange (Maclura). Osage Orange. 
All species suffered most severely from defoliation on 
the sides from which the storm came, while the worst 
injury to twigs and branches occurred in the tops of the 
trees and usually on such exposed branches as were most 
nearly at right angles to the hail. This occasionally 
caused the opposite side of the tree from which the storm 
came to have more wound injury to bark than the side 
from which the storm came. In four Carolina poplars 
which were examined it seemed that less bark injury 
occurred than in common cottonwood, and it is thought 
that the sharper angle of branching had much to do with 
this. Unfortunately time did not permit a search for a 
sufficient number of these trees to determine this point. 
Trees with flexible branches suffered less than those 
with stiff branches. Species with small twigs or with 
hard wood suffered less than those with large twigs and 
