184 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



30. The Canker of the Scots Pine caused by 

 Dasyscypha subtilissima^ Cooke. 



By A. W. BoRTHWiCK, D.Sc, and Malcolm Wilson, D.Sc., F.L.S., 

 Lecturer in Mycology in the University of Edinburgh. 



During recent years several accounts have been given 

 of the occurrence of the larch canker on various species of 

 Finns. Hopkinson^ has recorded its occurrence on Pinus 

 laricio, and points out that it may also be found on 

 P. sylvestris and P. austriaca. Massee - has also recorded its 

 occurrence on the Scots and Austrian pines as well as on the 

 silver fir. 



Our present know^ledge goes to show that the fungus is not of 

 infrequent occurrence on the above-mentioned species. It must, 

 however, be borne in mind that Dasyscypha Willkonwiii is not 

 by any means the only species of the genus which produces 

 canker on these trees, and it is possible that some confusion 

 has arisen owing to the great resemblance which exists between 

 the fructifications of the several species which cause disease in 

 conifers.^ 



Lagerberg*" has recently pointed out that in Sweden 

 D. fuscosanguinea, Rehm, produces a canker on the pines which 

 closely resembles that caused by D. Willkoimnii on the larch. 

 This species, however, has not been recorded in this country up 

 to the present. D. caliciformis, Rehm, has been shown by 

 Wagner ^ to be parasitic on Pmus sylvestris, P. excelsa and Abies 

 pectinata in Germany. 



^"The Occurrence of Larch Canker {Dasyscypha Willkommii) on the 

 Austrian Pine," Quart. Journ. of Forestry, vol. vii. , p. 287, 1913. 



^" Larch and Spruce Fir Canker," ybwrw. ^o^. of Agnc.,vo\. ix., p. 176, 

 1902. 



*D. calycina, Fckl., a saprophytic species, has been looked upon by some 

 investigators as identical with D. Willkommii. Both Hartig and De Bary, 

 however, considered the two species to be distinct, and their independence has 

 been recognised in recent lists of British fungi. 



^ " Studier iifverden Norrliindskatallens sjukdomar, Sarskildt med hiinsyn till 

 dess foryngring." (Studies on the Diseases of the Northern Pines with special 

 reference to their Regeneration.) Mitteil. a.d. foj-stl. Versnchswesen 

 Schwedens, Heft 9, 1912, S. 135. 



* " Beitriigezur Kenntniss der Pflanzenparasiten, Zeit. fur Pflanzenkrankh., 

 Bd. vi., p. 321, 1896. 



