TAKEW'O HEMMI 3 1 1 
were produced on the cut surface. The presence of the mycelium in the 
deep wood is also easily proved under a microscope in the stained sections. 
17. Prevention and Cure. 
(a) Cut off all dead or diseased branches, and burn them up as soon as 
possible. We can not cure them by a surgical operation as in the case of (b), 
for the mycelium of the causal fungus is living deeply in the woody portion. 
If the cut surfaces are large, paint them at once. 
(b) If the diseased portion is on the large limb or the trunk, we can 
cure them only in the case of the young stage of the canker. Carve off the 
affected bark and even the woody tissue of the diseased portion with a sharp 
knife or with other cutting instruments as thoroughly as possible. Wash the 
cut surface at once with a powerful fungicide such as O.05 or 0.1 °j 0 corrosive 
sublimate, and, after a few days, paint the surface with a thick paint. In this 
operation, the cut bark and woody tissue must be burnt up at once, without 
leaving them in the garden or the orchard. 
(c) Take all possible care to prevent external injuries to the healthy 
trees. 
(d) Take care to prevent injuries to the bark by insects, such as Sesia 
heel or. 
(e) Cut otf all dead twigs and other dead portions, and keep the trees 
clean. 
(f) To prevent the infection of the disease, spray the trees with the 
Bordeaux Mixture or some other fungicide before the leaves or the flowers 
conie out in the spring. But in the case of ornamental trees, a dirty fungi- 
cide such as the Bordeaux Mixture should be avoided. 
