62 EXPERIMENT STATION RECORD, 



The cankers of Plowrightia morbosa in their relation to other fungi, J. R. 

 Weib {Phytopathology, 4 (1914), No. 4, pp. 339, 340).— The author states that 

 throughout Montana the cankers formed by this parasite on Prunus and Ame- 

 lanchier are frequently infected by Fames igmarius. Not infrequently the same 

 knots are infected by Nectfia cinnaharina, and in one instance Stereum hirsutum 

 and Polystictiis hirsuttis had become established in the plum knots. The fungus, 

 which is well known on cultivated species of Prunus, is reported occurring on 

 four species of Prunus in the northwestern part of this country. 



Some notes on the black knot of plums and cherries, J. A. McClintock 

 {Rpt. Mich. Acad. Sci., 15 {1913), pp. 142-144)- — Giving an account of studies 

 with Plowrightia morhosa on plum and cherry trees during 1911-1913, the 

 author states that some asci were found able to shoot their spores to a distance 

 of more than 1 cm. upward, and that these spores germinated within 48 hours, 

 but only from the larger of the two cells. Mycelium developing from portions of 

 diseased branches and pycnospores developing therefrom did not produce in 

 plum or cherry trees tested the characteristic symptoms of black knot. Mycelium 

 of P. morbosa could not be induced to pass from diseased grafts to sound wood, 

 but knots did develop on neighboring bi'anches, and as it was too early for 

 conidia to be present, it is concluded that these infections resulted from asco- 

 spores shot out from knots on the diseased graftwood. No results were obtained 

 from attempts to inoculate with conidia or to germinate conidia in drop cultures. 



Diseased twigs cut at random from plum trees November 3, 1912, showed no 

 asci or spores at that time, but these twigs left on the ground as if dropped in 

 pruning showed some perithecia with ascospores on most specimens December 

 25. Twigs left on the ground until March 12, 1913, developed perithecia which 

 proved able to shoot their spores, this fact showing such twigs to be a possible 

 source of infection after lying on the ground all winter and suggesting their 

 immediate destruction when cut from the trees in autumn. 



Dead-arm disease of grapes, D. Reddick {New York State Sta. Bui. 389 

 {1914), pp. 463-490, pis. 6, figs. 3). — In continuation of a previous publication 

 (E. S. R., 21, p. 148), the author describes a disease of grapes which is said to 

 occur on practically evei-y variety of grape grown commercially within the 

 State, and it is known to be present in practically every grape-growing section. 



The most striking symptoms of the disease are the presence of bare arms in 

 the spring and the occurrence of dwarfed, crinkled, yellowish-colored leaves 

 during the early part of the growing season. The cause of the disease is said to 

 be Cryptosporella viticola. The fungus has been studied and its pathogenicity 

 established by numerous inoculation experiments. 



The method of control described includes the marking and removing of all 

 vines showing symptoms of the disease. Suckers originating from beneath the 

 surface of the gi'ound are said to develop strong and vigorous Aines almost in- 

 variably unless infected by spores during the first few weeks of their develop- 

 ment. 



"Dead arm" of grapevines, F. H. Hall {New York State Sta. Bui. 389, 

 popular ed. {1914), pp. 4y />'«• ^)- — -^ popular edition of the above. 



Fungus diseases [of cranberries], H. J. Feanklin {Ann. Rpt. Cape Cod 

 Cra/nherry Growers' Assoc, 26 {1913), pp. 24-29). — In the course of a more 

 general report, the author details experiments looking to the control of blos- 

 som end rot of cranberries. 



It is believed that fertilizers will give their best results in forcing fruit pro- 

 duction only when the vines are comparatively free from fungus disease. It is 

 thought that injury of some sort could in some instances be traced to spraying 

 while in bloom with lime sulphur, with Bordeaux mixture, and with nitrate of 



