444 THE MONTHLY BULLETIN. 



or into the trunk of the tree. Water shoots are often attacked. The 

 disease is usually indicated by the appearance of the bark : the soft 

 bark presents a water-soaked appearance and finally becomes blackened 

 and shriveled. The organisms may, hoivever, extend to a distance of 

 several inches or even a foot heloiv the water-soaked area. If the disease 

 ceases to spread rapidly there is a line between the dead and the 

 apparently live wood. Sometimes the bark becomes broken and a 

 gummy exudation appears. The pear blight bacteria winter over in 

 relatively few affected branches, under conditions where moisture is 

 sufficient and protection is furnished from drying out. The essential 

 steps in pear blight control, according to Duggar, consist in the 

 following : 



' ' In pruning out the blight in situations where it may winter over, 

 if all blight could be thoroughly pruned out of the orchard during the 

 fall and winter, there would probably be no opportunity for infection 

 the following season, except from other orchards. In practice the 

 pruning of the blight during the winter is not so easy, as it requires 

 care and the keenest eyesight. It may be necessary to go over the 

 orchard several times. Pruning during the growing season is also 

 practised, but it is not so effective. This pruning has not proven such 

 a great success, on account of the fact that infection may be constantly 

 taking place. Moreover, when the l)light is rapidly extending in the 

 limb or trunk, it is difficult to determine the extent of the region 

 affected. Carelessness in pruning of nursery stock may actually result 

 in spreading the disease to practically all the trees. The knife should 

 be promptly applied wherever a limb or trunk may be saved. Disinfect 

 both pruning tools and cuts with corrosive sublimate, 1 to 1.000." 



