Bui. 360, U. S. Dept. of Agriculture. 



PLATE IV. 



FIQ. 1. NEEDLES OF DOUGLAS FIR FROM A NORMAL BRANCH (AT THE RIGHT) AND 

 OF A MISTLETOE BROOM ON THE SAME TREE, SHOWING THE DIFFERENCE IN SIZE. 



FIG. 2. YELLOW PINE AT THE HEAD OF A CANYON, SHOWING MISTLETOE INFECTION. 



Note that the heaviest infection occurs on the immediate edge of the canyon and that the 

 intensity of the infection decreases as the distance from the brow of the canyon increases ; 

 also that the upper crowns of the infected trees are becoming very thin. 



