Trees and Timber 



393 



and die as though frosted. Young leaves and shoots are 

 killed and by their death induce abnormal branching, result- 

 ing in a compact head. The disease seems limited to young 

 trees. 



Bordeaux mixture is advised — three or more sprayings. 



Fig. 208. — Maple tar-spot. After Heald. 



Thrombosis (Verticillium). — -Leaves wilt and branches 

 die due to plugging of the veins by the fungus. Dark streaks 

 show in the wood of affected twigs. 



MULBERRY 



Blight (Bacterium niori B. & L.). — Upon the leaf small, 

 reddish-brown spots, pellucid when moist, are produced. 



