80 EXPERIMENTS IN BLUEBERRY CULTURE. 



unless promptly checked. The most satisfactory treatment was to 

 syringe the j^lants once or more a day with a swift spray of water, 

 repeating the treatment until the animals were cleared off. 



A pathological condition observed in the summers of both 1908 and 

 1909, at first supposed to be physiological in cause, has now been 

 traced to an insect. The young leaves of tender shoots become semi- 

 transparent or " watery " in appearance, remain small, develop a 

 faintly rusty color on the lower surface, tend to become slightly 

 cockled, and sometimes turn brown and wither. It was finally ob- 

 served that these leaves were infested with a very minute animal, 

 much smaller than a red spider and when not in motion difficult to 

 distinguish with a strong hand lens. Specimens submitted to Mr. 

 Nathan Banks, of the Bureau of Entomology, were identified by him 

 as a mite of the genus Tarsonemus and belonging probably to an 

 undescribed species. 



A similar and perhaps identical mite had done considerable dam- 

 age to young seedlings in the greenhouse during the wanter of 1908-9, 

 its presence being indicated by the conspicuous cockling of the 

 leaves. The difficulty had then been met by the pruning of the 

 affected twigs. It was obsei-^^ed, however, in the summer of 1909 

 that the mite producing the watery appearance of the leaves did not 

 occur on outdoor plants fully exposed to rain and dew, but only on 

 plants partly or wholly protected by glass. It is suggested, therefore, 

 that frequent syringing w^ith water m'ay be the proper means to 



control this mite. 



On the whole, this species of blueberry when properly grown may 

 be regarded as unusually free from the depredations of fungi and 

 insects. 



IMPROVEMENT AND PROPAGATION. 



(37) The parent plant of the swamp blueberry seedlings, the culture of 



WHICH has been described, BORE BERRIES OVER HALF AN INCH IN 



diameter. 

 The parent of the blueberry seedlings of 1908 was a bush of 

 Vaccinium eorymhosvm selected at Greenfield, N. H., in July, 1908, 

 after three summers of cursory observation in the mountains of 

 southern New^ Hampshire and three wrecks of diligent search in 

 the summer of 1908. The bush grew at an elevation of 950 feet 

 above the sea. It stood with many other blueberry bushes in an 

 old, brushy, mountain pasture, in permanently moist but not swampy 

 soil. It was about 7 feet in height, and the largest of the several 

 stems was about 2 inches in diameter. The plant was old and some- 

 what decrepit, the tops on some of the stems being partially dead. 

 Some parts of the bush, however, w^ere in full vigor, with robust 

 foliage and twigs. The leaves were dark green above and pale 

 glaucous green beneath, with entire margins, and smooth on both 

 sides except for a slight pubescence on the midrib and principal 



19?. 



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