150 MANUAL OF FRUIT DISEASES 



last of June the supply is exhausted. The soil readily dries out 

 and the tree suffers from a lack of moisture ; hence its growth 

 stops and the tissues harden. In July water of irrigation is 

 supplied and many trees start into growth again ; the result is 

 that such trees possess soft and immature tissues which with the 

 advent of winter are killed or severely injured. 



Control. 



Our incomplete knowledge of the cause of the disease makes 

 the problem of control difficult, or even impossible. The follow- 

 ing recommendations based on the information at hand are 

 offered : (1) avoid planting apple-trees in soil where marl is 

 close to the surface ; in this way shallow roots and an inadequate 

 water-supply are avoided; (2) increase the depth of the soil 

 by deep plowing before the orchard is planted, by the addition 

 of straw and by plowing under green manures such as vetch, 

 clover or rye; (3) water of irrigation should be used judi- 

 ciously. The amount of water should be lessened with the 

 approach of autumn in order that the tissues may properly 

 harden before winter. 



REFERENCE 



Paddock, W. Plant diseases of 1901. Apple tree rosette. Colorado 

 Agr. Exp. Sta. Bui. 69 : 6-9. 1902. 



SEPTOBASIDIUM-CANKER 



Caused by Septobasidium pedicillatum (Schw.) Pat. (= Thelephora 

 pedicillata Schw.) 



This is not a well-known disease. It was first noticed in 

 America about 1889 in Texas and Alabama. In 1911 it was 

 described from North Carolina, and is now said to occur in 

 West Virginia and Georgia. Outside of the United States it is 

 found in Cuba, Ceylon and New Zealand. In this country at 

 least it should not be expected to prove a serious menace to the 



