seed origin. He determined that R. pseudotsugae was oi minor 

 importance in stands from seed originating below 1,500 meters. 



In a review of forest patholog) in North America, Peace (40) 

 described R. pseudotsugae as consisting of several varieties "varying 



in the form of their fructifications and spoil's, and probably also in 

 their pathogenicity." 



Ellis (14) reported on new conifer diseases in the southwestern 

 United States in 1939. Among them was R. pseudotsugae on Douglas- 

 fir associated with an imperfect stage very similar to Rhabdogloeum 

 pseudotsugae. Ellis and Gill (15) published the new Rhabdogloeum 

 as Rhabdogloeum hypophyllum Ellis Sc Gill. R. hypophyllum was 

 found repeatedly preceding Rhabdocline pseudotsugae on Douglas- 

 f ii needles in the Southwest. The authors proposed that this fungus 

 was probably the true imperfect stage of Rhabdocline pseudotsugae 

 since Rhabdogloeum pseudotsugae was very rarely associated with 

 the perfect stage. 



In Switzerland, Terrier (59) working with Adelopus gaumanni 

 Rohde, the cause of a needle disease of Donglas-fir, found Rhabdo- 

 cline pseudotsugae on the same trees and even the same needles. 

 This was the first published report of the two organisms being found 

 on the same trees and also the first record of R. pseudotsugae in 

 Switzerland. The fungus was believed to have been introduced 

 southward from Germany. 



In a report on diseases of Donglas-fir in Germany, Zycha (72) 

 compared the damage caused by R. pseudotsugae with A del op us 

 gaumanni and found the former more destructive since needles were 

 killed within a year after infection, w r hereas needles infected with 

 A del opus gaumanni remained on the tree for three years. Once again 

 the resistance of the green form to R. pseudotsugae was strongly 

 emphasized, but later Zycha (73) reported the resistance as merely 

 a wide variation in susceptibility. 



Meyer (35) in 1951 gave the recent geographical distribution of 

 the disease in Germany, and dining the course of his investigations, 

 concluded that differences in resistance were perhaps due to indi- 

 vidual tree differences rather than to racial characteristics. He 

 considered Rhabdocline needle cast as the most serious disease ol 

 Douglas-fir in Germany. The amount of infection was reduced by 

 two spra\ applications of copper lime in May, but control was 

 ineffective clue to the lack of adhesion of the spia\ to the lowei 

 sin faces of the needles. 



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