

TABLE 1 





Spray Materials Used in the Control of 





Rhabdocline Pseudotsugae (a) 





Toxicant 



Common name <b> 



Concentration 



of toxicant 



per cent 



Copper sulfate 



Bordeaux mixture 



1.0 



Calcium polysulphides 



Lime-sulfur 



0.7 



Ferricdimethyl-dithio- 

 carbaiuate 



Ferbara 



0.3 



N-trichloromethylmercapto- 

 4-cyclohexene-l-2-dicarboximide 



Captan 



0.2 



Dodecylguanidine acetate 



Cyprex 



0.2 



Cycloheximide 



(Beta-2- (3, 5-dimethyl- 



2-oxocyclohexyl)-2-hydroxy- 



ethyl-glutarimide 



Actidione BR 



0.001 

 0.0005 



Cycloheximide Actidione S 0.0005 



(Beta-2- (3, 5-dimethyl- 

 2-oxocyclohexyl)-2-hydroxy- 

 ethyl-glutarimide semi- 

 carbazone 



(a) A mixture of Dreft, flour, and water was used as a control. 



<b) The Bordeaux mixture was a 4-4-50 formula as recommended by Boyce (5). The Lime- 

 sulfur was manufactured by Coulard and Olena, Inc.; Ferbam by E. I. duPont Co.; 

 Captan by the California Spray Chemical Corporation; Cyprex by American Cyanamid 

 Co.; and the Cycloheximide derivatives by the Upjohn Co. 



that lammas shoots were developing while ascospores were still 

 being produced. Thus a total of five spray applications were made 

 on each tree at Cortland and seven at Camden. The 1958 spray 

 programs at Jericho and Woodstock, Vermont, were restricted to 

 two applications of each trial fungicide; the first application being 

 made as the Douglas-fir buds were beginning to open and the second 

 10 days later. 



To obtain a measure of the efficacy of the various spray materials 

 used, observations were made in April of the year following treat- 

 ment. A visual inspection method was used to compare the appear- 

 ance of the sprayed foliage with that of unsprayed trees. The relative 

 greenness and retention of the past year's needles was the best 

 criterion for assaying the effectiveness of the different fungicides. Of 

 importance, but secondarily so, was the relative number and develop- 

 mental stage of the fruiting bodies of R. pseudotsugae. To facilitate 



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