Diseases and Injuries 



While trees have much to contend with from the attacks of 

 insects, they are also exposed to fungus infections, and the 

 struggle against disease is constant. 



Among some of the most prominent of these which affect 

 the wood and fruit are Blight, Canker, Crown-gall, Mildew, 

 Scab, Rust, Brown Rot, and Bitter Rot. Heavy pruning will 

 check Blight and often save the trees. Blight results from 

 immature wood, the sap of which is frozen in times of low 

 winter temperatures. The blossoms are first affected in the 

 spring through the circulation of diseased sap. Bees in seeking 

 the nectar in blossoms spread the disease among healthy blos- 

 soms and in this manner, entire orchards become infected. 

 Prompt pruning on first evidence of the disease will save many 

 trees. Cut back to sound healthy wood and disinfect the pruning 

 tools with a weak solution of carbolic acid, after the pruning 

 of each tree. 



Reject trees that are received from the Nursery with marked 

 growth of Crown-gall upon them — an unnatural enlargement 

 close to the union between the tree and the root. 



Canker is the result of fungus that develops in the wood of 

 the tree through some wound that has been made upon the 

 bark. As the disease progresses it often encircles a branch, 

 which dies. It also makes deep cavities in the body and large 

 branches of the tree. 



Mildew attacks the foliage and new growth of trees in the 

 nursery, as also of the orchard. 



Root Rot attacks the roots of trees. Such trees should be 

 taken out and burned. 



Rust is a disease produced from a fungus that develops upon 

 the red cedar trees. The spores of this fungus are carried to 

 apple trees near them, when both the leaves and fruit are cov- 

 ered with dark orange colored spots which injure the foliage 

 and ruins the fruit for sale. Spraying with Lime and Sulphur 

 when buds are swelling, and later the fruit, as before directed, 

 will largely control this disease. 



The Rot in apples is the result of Monilia fungus that enters 

 the apple from any bruise or broken part of the skin. The 

 spores of this fungus on gaining entrance to the flesh of the 



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