DISEASES OF SPECIAL CROPS 105 



tions for avoiding the blight were deduced, and tested by 

 Waite.' They have proved their worth in many states.^ 



1. Pruning in winter when the tree is dormant pro- 

 motes growth and favors blight. Withholding the pruning 

 knife, which may not otherwise be best for the tree, will 

 reduce this tendency. 



2. Overstimulation with fertilizers, especially those 

 rich in nitrc^en, is to be avoided. 



3. A wel^ultivated tree is more inclined to blight 

 than one gro^ig on sod or untilled land. 



4. In irrigatSl orchards a reduction of the water supply 

 to the minimum^,s been found effective. 



5. The only r«lly satisfactory method of controlling 

 pear blight (that»s, exterminating the microbe that 

 causes it) is by cuWng out and burning every particle of 

 blight when the trA are dormant. Not a single case of 

 blight should be allcjved to survive the winter, either in the 

 orchard or within Balf a mile of it. Every pomaceous 

 tree, including the »ple, pear, quince, Siberian crab apple, 

 wild crab apple, tip mountain ash, service berry, and all 

 the species of Crafegus, or hawthorns, should be examined 

 for this purpose J the blight being the same in all. The 

 orchardist shouM not stop short of absolute extermination 

 in every case, fw a few trees or branches overlooked may 

 go a long way^TOward undoing all his work. Cutting out 

 the blight may loe done at any time in the winter or spring 

 up to the period when growth begins. The best time, how- 



* Taken in modified form from M. B. Waite, U.S. Dept. Agr. Yearbook, 

 1895. i 



2 Whetzel, m H., and Stewart, V. B., N.Y. (CorneU) Agr. Exp. Sta. 

 Bui. 272. 



