12 



gall on apple trees, which appears to be more injurious in the 

 warmer parts of the country. Nevertheless, no orchardist 

 should accept material affected by this disease. 



While the specific bacterial organism has been isolated, 

 and many cross inoculations made, there is yet much to be 

 learned concerning the relation of a particular type of gall 

 to another. Extensive investigations made by Smith and 

 Townsend seem to indicate that the organisms causing crown 

 gall on the raspberry and apple are similar, yet our raspberry 

 has had galls for years, while apple trees have been free from 

 them until comparatively recently. Crown gall was not 

 observed here until certain infected stock was obtained from 

 outside the State. Where infected stock has been planted 

 and cultivated, the disease spreads from one field to another, 

 and seedlings raised on soil which was formerly free from 

 the organism become infected. It is possible that much of 

 our infected stock already planted will pull through and 

 develop into bearing trees ; but it is a wise precaution to se- 

 cure clean trees when planting. 



Crown gall, as its name implies, is characterized by a gall 

 formation near the crown, which causes a distortion of the 

 tissue, and in very severe cases it interferes with the function 

 of the plant to such an extent that death results. 



Hairy root (Fig. 8), which is characterized by the ab- 

 normal production of roots, giving a hairy effect, appears to 

 be a similar trouble, although it is much less common with us. 



Baldwin Spot ok Fruit Pit. 

 This spot, which has been known by several names, has 

 been present in Massachusetts since 1898 at least, and has 

 been confined, to our knowledge, to the Baldwin in this sec- 

 tion. It is characterized by small spots or indentations on 

 the surface of the fruit, ranging from 2 to 4 millimeters or 

 more in diameter, which are scarcely perceptible to one not 

 acquainted with the disease. The spots are usually so in- 

 significant that expert judges of fruit have been known to 

 place promium,s at fruit shows on apples badly affected with 

 this trouble. In cutting open an affected fruit, numerous 



