82 BARRINGTON MOORE Vol, III, No. I 



Jack pine and pitch pine respond more to humus than do red pine or 

 cedar. There is a possible indication that trees growing naturally on sterile 

 soils are more strongly influenced by humus than those requiring better soils 

 with other available nutrients than humus. 



Cedar showed the beneficial effects of humus much less than the other 

 species. 



Wheat responded markedly to the humus, but less so than the coniferous 

 trees except cedar. On the humus it showed the influence of the high 

 nitrogen-low carbohydrate ratio. 



Alkalinity produced by heavy applications of burnt lime was extremely 

 unfavorable to all the trees except cedar. Sugar maple transplants died 

 within 5 days, except for two on limed sand. A large proportion of the 

 seedlings of the other species died, and those which survived made poor 

 growth. Cedar came up on all three of the strongly limed soils, instead of 

 on only the sand and humus as in the unlimed series, and grew slowly. The 

 conifer roots on alkaline soils were brown and shriveled. 



Alkalinity is more unfavorable to trees than acidity of the same departure 

 from the neutral point. Cedar and other trees of lime soils may be an 

 exception. 



The toxicity of the burnt lime appeared to diminish somewhat after about 

 40 days' exposure, but still remained strong enough to be very unfavorable. 



Wheat grew practically as well on the heavily limed as on the unlimed 

 humus, showing the necessity for caution in applying to trees the results of 

 nutrition studies in herbs. 



In the lightly limed series growth in height, root growth, and green weight 

 on the sand and mixture of sand and humus equaled or surpassed that on the 

 stronger lime in spite of 15 days' later start. On the humus of this series 

 all species excelled those on the more heavily limed humus in all respects and 

 to a marked extent. Cedar did better on this series than on either of the 

 others. 



Wheat grew remarkably well on the light lime series, far surpassing that 

 on the other soils. 



LITERATURE CITED 



1. Coville, F. V. 



'10 Experiments in Blueberry Culture. U. S. Dept. Agr. Bu. PI. Ind. Bull. 193 

 (especially pp. 26-28). 



2. Fernald, M, L. 



'19 Lithological Factors Limiting the Ranges of Pinus Banksiana and Thuja 

 occidentalis. Rhodora, Vol. 21, No. 243, pp. 41-67. 



3. Hawley, R. C. 



Unpublished MSS. in library of Yale Forest School. 



4. Hesselman, H. 



'17 Om vara skogsforyngringsatgarders in verkan pa saltpeterbildringen i 

 marken och dess betydelse for barrskogens foryngring. Meddel. fran 

 Statens Skogsforsoksanstalt, Sweden, pp. 923. 



