640 JOURNAL OF FORESTRY 



are not available, but it was determined that considerable water loss 

 takes place on sunny days which often occur during midwinter in this 

 region. For example, from February 24 to February 28, 1920, the 

 loss per plant (3-4 year-old transplants) was as follows: Pinus pon- 

 derosa, var. scopulorum 3 grams, Pinus aristata 2.7 grams, Pseudotsuga 

 taxifolia 7 grams, Picea engelmanni 6.3 grams. The soil in the pots 

 was frozen solid excepting that in the afternoons it thawed to a depth 

 of two or three inches. At the present writing, April 5, 1920, one of 

 the yellow pines is dead, and the remaining three, though apparently 

 alive, have many dead needles ; Douglas fir and Engelmann spruce are 

 all alive but have a few dead needles (the tip of one Douglas fir is 

 dead) ; bristle cone pine shows least injury of all and appears prac- 

 tically normal. Since in average years the soil to a depth of two feet 

 remains frozen during continuous periods of thirty to ninety days in 

 this region, and during these periods clear weather may prevail during 

 continuous intervals of ten days or more, winter killing is to be ex- 

 pected. The fact that relatively little winter killing actually does 

 occur is attributed to the fact that the ground throughout the winter is 

 usually covered with from two to four feet of snow which protects 

 small seedlings from transpiration. 



This investigation by Weaver and Mogensen adds in no small way 

 to the existing knowledge of conditions relating to the early establish- 

 ment of forest trees. Unfortunately but few ecological investigations 

 carried on by college professors are more than very remotely applicable 

 to forest problems, and therefore such contributions as the present 

 one will always be welcomed by forest research w^orkers. G. A. P. 



Weaver, J. E. and Mogensen, A. Relative Transpiration of Coniferous and 

 Broad-leaz'ed Trees in Autumn and Win4cr. (With 18 figures.) Botanical 

 Gazette, Vol. LXVIII, No. 6, December, 191i^. 



SILVICULTURE, PROTECTION, AND EXTENSION 



H. G. Champion describes in considerable de- 

 Effcct of Fire tail the eftect of the disastrous seastDU of 1916 

 on Chir Pine on the chir pine in the West Almora forests. 

 Since the chir pine is very similar to our west- 

 ern yellow pine, the results of this study are of interest, especially to 

 those who are combatting the dangerous propaganda of "light burn- 

 ing." A digest of Champion's conclusions is as follows : 



