66 The Plant World. 



that on page 62, that the capillary film system tends to extend 

 itself to the adjacent unwetted particles. The harmonization 

 lies in a consideration of the velocities of the several processes. 

 The movement of water onto unwetted material is apparently 

 very much slower than is its movement through film-systems 

 already in existence. There seems to be a considerable passive 

 resistance to wetting. When the surface soil is once dried out 

 it is not easily rewetted and the interstitial evaporation, small 

 though it is, is sufficient to cope with the rewetting tendency 

 of the water below. This is probably also the explanation of 

 the fact noted in the footnote on page 62, that in a soil column 

 into which water has risen by capillarity the decrease of water 

 content at the top limit of rise is more abrupt than is to be ex- 

 pected. * 



Bureau of Soils, 



U . S. Department of Agriculture, 



Washington, D. C. 



CONIFERS WITHOUT NORMAL WHORLS. 



F. J. PHILLIPS. 



For some time branchless trees have been known in Europe, 

 especially in Italy and in Baden. Occasional specimens of Nor- 

 way spruce have been reported without branches but with a 

 slender leader which has long, thick needles and no lateral buds. 

 As a rule these trees die early, but one in Italy has an approxi- 

 mate age of fifty-five years while another noted in Bavaria was 

 eight vears old. Two specimens of white fir have also been re- 

 ported. X 



During the past summer a somewhat similar phenomenon 

 was noted on Mexican pinon (Pinus cembroides Zucc.) and white 

 fir (Abies concolor Parry) in the Huachuca Mountains, which lie 

 along the Mexican boundary in Arizona. A group of eighteen 



♦This phenomenon could probably be made to yield an experimental proof of the passive 

 resistance to wetting. If there is such a resistance, the height at which water will be 

 held by capillarity in a given soil column ought to be different when equilibrium is 

 approached from above and when it is approached from below. That is, the upper 

 limit of the moist soil should be higher in a column which had been originally saturated 

 and allowed to drain, than in one which had been originally dry and into which water 

 had ri=en from below. So far as I am aware, there are no reported experiments of 

 sufBcient accuracv for the testing of this ijomt. 



J"EineastlosteFichte." ForstwissenschaftlichesCentralblatt. January, 1910, pp.59-60. 



