196 Report of the Botanist of the 



about 25 per ct. of the latest sweet cherries. Orange Co. cor- 

 respondents report but little damage from it. At Kinderhook, 

 Columbia Co., it was " unusually developed." In the vicinity of 

 Delmar, Albany Co., it is reported to have destroyed about 10 

 per ct. of the crop; and in one orchard about 50 per ct. A cor- 

 respondent at Highland, Ulster Co., reports the loss of one-half his 

 crop; but from personal observations we would say that, in gen- 

 eral, cherries suffered but little from rot in that locality. 



LEAF spot. 



(Cylindrosporium padi Karst.) 



This disease has occurred in small amount over the whole dis- 

 trict, but no case has been reported in which it has done serious 

 damage. 



BLACK KNOT. 



(Plowrightia morbosa Sacc.) 



Throughout the Hudson Valley black knot is common on culti- 

 vated cherries of some varieties. English Morello probably suf- 

 fers most. Trees of this variety are frequently ruined by it. At 

 Middle Hope, Orange Co., Montmorency and Early Richmond 

 cherries are said to knot considerably. At Coxsackie, Greene Co., 

 we found knots on English Morello cherries producing summer 

 spores as early as June 1. Black knot is exceedingly common on 

 plums over the whole district. In former years it has been a 

 veritable scourge. With these facts before us it is an interesting 

 observation that, although the wild black cherry, Prunus serotina 

 Ehrh., is very common and we have searched carefully, not a sin- 

 ' pie specimen of hlacJc knot has been found upon it}^ 



The wild red cherry, Prunus pennslyvanica L. f., is common in 

 Albany Co., but we have failed to find any affected by black 



14 Peck, also, lias noted the absence of black knot from Prumis serotina in 

 Eastern New York. See Forty-Second Ann. Kept. N. Y. State Mus. Nat. Hist.. 

 1888: 125. On Long Island, black knot is abundant on this species. 



