276 



JOURNAL OF FORESTRY 



District Office of the Forest Service/° gives the results obtained on 

 the different experimental areas for the years 1917 and 1918. 



Table 1. 



' Taps yielding only a trace of gum not counted. 



" Five plugs had vi^orked out during the winter from trees with double taps. 



" Four plugs had worked out or were broken and not replaced. 



Although the results are disappointing in that the yields are smaller 

 than it was hoped they would be, it is possible that, by boring the holes 

 nearer the ground, selecting the most favorably located stands, and 

 continuing the observations over a longer period, the yield of oleoresin 

 could be materially increased. Further experiments along these lines 

 are contemplated. 



EXAMINATION OF THE OLEORESIN 



The material sent to the Laboratory consisted of two distinct 

 products, one a thin liquid and the other a thick gum. The former 

 product, a mobile, light brown, opaque liquid, is apparently the sap 

 of the tree. It has a specific gravity of 1.110 at 20° C. and was shown 

 to contain 22.1 per cent of 8-galactan.^^ When oxidized with nitric 

 acid the galactan gave crystals that melted at 212°. Pure music acid 

 melts at 215°. The oleoresin has the consistency of honey, is light 

 amber in color, and is somewhat cloudy because of the presence of 



^° The field work was conducted and the reports were compiled by C. N. "Whit- 

 ney, Forest Examiner, assisted by the Forest Rangers on the different forests. 

 The reports, which are on file in the library of the Forest Products Labora- 

 tory, give complete data regarding the climatic conditions, soil, and topography 

 of the different experimental areas, with detailed informatfon regarding the 

 individual trees tapped. 



"Journal of Industrial and Engineering Chemistry, vol. 8, p. 494. 



