346 



BULLETIN 226. 



FIG. 89. Collar rot of the King, showing 

 diseased and cracked condition of 

 bark. 



decay and frequently girdle the 

 tree. 



Treatment. Little can be done 

 except to treat the wound as any 

 other wound should be treated. If 

 the dead bark is cleaned away and 

 paint applied, it will delay the 

 decay of the wood. In some cases 

 this has preserved the wood and 

 the wound has healed over. 



The effective treatment must be 

 prevention. If hardy stocks are 

 planted and top-worked to King or 

 Esopus Spitzenburg, the trouble is 

 avoided. (See Fig. 92.) The losses 

 of Baldwin from this disease are 

 not very great, but are enough so 

 that it might pay to top-work them 



of this variety that are thirty years 

 old are affected. It is nearly as 

 serious on the Spitzenburg. The 

 Baldwin is more affected than the 

 Spy, Greening or Russets, but none 

 of these are as badly affected as are 

 the King and Spitzenburg. It 

 seems to be worse on poorly drained 

 land than on good soil. 



Cause. The cause is not defi- 

 nitely known. It is probably some- 

 times due to winter injury, but this 

 does not seem to account for it in 

 all cases. Whatever the original 

 cause, the wound once made be- 

 comes infected by the wood-rot 

 fungi, which cause the trunk to 



FIG. go. Collar rot of the King. The 

 same tree as in Fig. 89 with the dead 

 bark removed. 



