74 Report of State Board of Horticulture. 



deformans. The fungus lives within the tissues of the leaf, 

 in the tender shoots, and in the buds. Within the past few 

 months I have learned that lime, sulphur and salt is a satis- 

 factory preventive of this widespread disease. The applica- 

 tion of this spray should be made three to five weeks before 

 the buds open in the spring. The treatment should be very 

 thorough ; or spray with bordeaux mixture six weeks, and 

 again three weeks later, before the buds begin to swell." 



FOR CRATER BLIGHT OF PEARS. 



Prof. C. W. Woodworth of Berkeley, California, says: 

 "The nature of the disease is somewhat obscure, but the evi- 

 dence seems to be that it is caused by an organism, and is 

 very similar to the dreaded eastern pear blight. It is not, 

 however, the same disease. Crater blight first appears as a 

 darkened spot, indistinguishable from any other form of 

 blight. Like other blights, it commonly begins at the point 

 on a branch where a twig is given off, or where one has been. 

 There is this difference however ; the crater blight extends 

 out only below the point of origin, whereas in other blights 

 the disease extends upward as well. The most characteristic 

 feature of this blight is the sharp line of demarcation between 

 the dead and live bark. When a spot has ceased to spread 

 there occurs a breaking in the bark, sej^arating the diseased 

 portion. This soon dries, and the spot appears like a crater. 

 The appearance is most striking when isolated spots are seen 

 on the larger branches. 



Treatment. — Cut out the dead and diseased tissue, clean and 

 w^ash with bordeaux mixture ; cut off all dead and blackened 

 limbs. 



Under date of July 27, 1896, Professor Woodworth adds : 

 "We have made some progress in the study of the disease, 

 in that we are very uniformly able to obtain pure cultures of 

 a peculiar bacillus. Inoculation experiments have so far 

 given only negative results. The disease occurs on many 

 varieties of pears and only a few apples. The crater blight 

 certainly occurs in Oregon. I have had very typical examples 

 from there, and obtained the usual bacterial cultures from it. 

 Economically, the crater bliglit in most localities is unim- 

 portant, but in some places it has done an immense amount 

 of injury." 



