350 Report of the Horticultuual DEPAnxMENT. 



a series of six ridges or convolutions In the wood surrounding a central 

 starting point, each one of whicli evidently marlied a year's growth of a 

 parasitic fungus. The fungus, Sphwropsis malorum Pk., which has been 

 shown to be the cause of the common New York apple-ti-ee canker, is 

 more active in its growth. With this disease large areas of bark may be 

 destroyed and the wood laid bare, or In other Instances the bark may be 

 much swollen and roughened, but the form of Injury desci-ibed above does 

 not occur. 



The appearance of the diseased limb, which was similar to that shown 

 in Plate LVI at 3, strikingly resembled the work of Neclria ditissima as 

 illustrated and described by European writers. However there was no 

 fungus fruit in evidence, and as I was unsuccessful in obtaining more 

 specimens the matter was dropped for a time. 



In the. latter part of May several specimens of diseased apple limbs 

 were received from East Homer, Cortland County, N. Y., that were similar 

 in appearance to the one from Nova Scotia, but in addition many portions 

 of the dead bark and wood were thickly studded with the minute, deep 

 red perithecia of a Nectrta. Among the specimens were examples of 

 recent infections as is shown at 1, in the plate, as well as cankers of 

 several years standing. The perithecia were abundant on all these speci- 

 mens, so there seemed little doubt but that the Nectria was the cause of 

 the diseased condition. 



On visiting the locality it was found that the fungus was evidently con- 

 fined to a small area and but few additional specimens were secured. 



Through the kindness of Professor F. C. Sears, Wolfville, N. S., more 

 specimens of the diseased apple limbs were obtained from that locality 

 in June and the perithecia of the Nectria were found to be abundant on 

 them. Professor Sears writes that this form of canker is doing serious 

 damage in some of the orchards of the Annapolis Valley. 



Specimens of the diseased branches were sent to Dr. R. Hartig, Munich, 

 Germany, for identification, who writes that the cankers are caused by 

 the fungus Nectria ditissima. 



So far as I know this fungus has not as yet been recorded as occurring 

 on apple trees in America, and its appearance in our orchards is of great 

 practical importance since it is a serious pest to European fruit growers," 



Since the above article was written, I have had an opportunity 

 of comparing the fungus with specimens of N. ditissima on 

 cankered apple trees which were collected for me in England by 

 Mr. H. Hadlow of this Station. There is no doubt as to its 

 identity. 



