iSTEW YoEK Agricultural Experiment Station. 193 



SUN-CRACK. 



On June 2 some apple-^ree trunks were observed at Ghent on 

 which the bark was loose and dead over areas from two to four 

 inches in widtb and from one to four feet in length. These in- 

 juries were on the southwest side of the trunks and usually, but 

 not always, extended quite to the ground. It first appeared in the 

 spring of the present year. The trees were unusually thrifty, 

 about seven years old and of the variety Willow Twig. They 

 stood in well drained soil. We are of the opinion that it was caused 

 by the sun's rays beating the bark intensely in early spring while 

 the soil about the roots was still deeply frozen. That is to say, 

 this is a case of what Hartig^ calls sun-crack (Sonnenriss). 



A sun-crack or perhaps sun-scald of apple tree trunks locally 

 known as " southwest blight " is of common occurrence in the 

 vicinity of Washington ville. 



BEOWN^ SUNKEN SPOTS ON THE FRUIT. ^° 



A disease of this description has been reported as occurring on 

 Greenings and Baldwins at Clintondale. 



APRICOT DISEASES. 



Apricots are not cultivated to any extent within thie district- 

 The only disease with which we met was one occurring at Ghent. 

 Some trees which have been planted for several years have been 

 dying off mysteriously one at a time for a few years past. A tree 

 may die either in part or wholly at any time during the growing 

 season. Some died in the spring of 1899. Just above th^e surface 

 of the ground the bark is dead, often for considerable distance up 

 the trunk; but the wood is not laid bare. Sometimes the bark shrinks 



OHartig, R. Text-Book of the Diseases of Trees (p. 296). Translated and 

 revised by Somerville and Ward. The Maemillan Co.: Xew York, 1894. Dr. 

 Hartig informs us that Fig. 159, which piirports to illustrate sun-crack, is 

 misnamed. The injury was caused by lightning. 



10 A description of this disease and an account of an investigation into its 

 causes are given in Bulletin 1G4 of this station. 



13 



