ORCHARD CARE 157 



blight is here, while not harming our native hazels 

 much. Many of the European and Asiatic hazels 

 brought to this country are very susceptible to the 

 blight while others, like the Byzance hazel, are prac- 

 tically immune. The selection then of blight-resisting 

 varieties remains one of the duties of the orchardist. 



In regard to the chestnut blight there is much 

 variation in degrees of tolerance shown by different 

 species or by individual trees. Our American sweet 

 chestnut, Castanea crenata, appears to be the most 

 vulnerable; next in order in Connecticut come the 

 Japanese chestnuts, then the European chestnuts, and 

 least of all the chinkapin varieties and species. Our 

 own chinkapin, Castanea pumila, and its variety, the 

 tree chinkapin, is sufficiently resistant to the blight 

 to thrive many years without becoming attacked, and 

 the same is true of another American chestnut, Cas- 

 tanea alnifolia, the alderleaf chestnut. Hybrids be- 

 tween these various chestnuts vary remarkably in 

 their tolerance of blight. 



In California a bacterial walnut blight is causing 

 much injury to nuts and foliage. The microbe has 

 not as yet been brought under control, and in fact 

 is spreading to the eastward. The way out of the 

 difficulty has consisted so far in the selection of 

 varieties of walnuts which resist the blight most suc- 

 cessfully. Some varieties are extremely vulnerable 

 to attacks from the blight bacterium, while others 

 resist so well that the orchardist suffers compara- 

 tively little from the enemy. We must always re- 

 member that Nature is quite as much interested in her 



