16 BULLETIN 1283, U. S. DEPARTMENT OF AGRICULTURE. 



Station 12. The soil at tjiis site is extremely thin and poor. In 

 fact, there is so little accumulation of organic matter, and the granite 

 is so slightly disintegrated that it can hardly be said that there is 

 any soil. 

 The equipment of this station consisted of: 



Maximum and minimum thermometers, in standard shelter, on the ground, 

 March 3, 1915, to February 29, 1916. 



Air thermograph, same location and period. 



Anemometer, 8 feet from ground, with register, same period. 



Sunshine recorder, electric thermometric, March 7, 1915, to September 10, 

 1915. 



Evaporimeter, inner-cell, Type 4, 1 foot aboye ground, February 16, 191S, 

 to September, 1920. 



1 and 4 foot soil thermometers, in iron pipes, the former from May 22, 1915, 

 and the latter from June 19, 1915, to February 29, 1916. Both from August 

 1, 1917, to September, 1920. One-foot iron pipe replaced by wooden tube, 

 April 26, 1918. 



Ground and soil-surface temperatures, May to September, 1920. 



Soil well, furnishing moisture samples at 1, 2, and 3 feet, from July 7, 1915, 

 to end of season, and also surface samples during season of 1917. 



F-1S: Fremofit high-ridge limber pine. — Elevation, 10,300 feet; 

 aspect, flat. This station presents the conditions existing on an 

 exposed ridge at the northeast base of Pikes Peak, where much of 

 the original forest was destroyed by fire many years ago. For the 

 most part this forest was of spruce. Limber pine is now coming in 

 all over the burned area, and in the more sheltered spots the spruce 

 followers are already appearing. At present the stand of limber 

 pine about Station 13 is not sufficient to furnish any protection. 

 The chief characteristic of the site, therefore, is an intense exposure to 

 both sun and wind. (See PL V, fig. 2.) It is interesting to note that 

 a few specimens of western yellow pine may be found in the vicinity of 

 this station where the exposure is less severe. Apparently they are 

 of the same age as the first group of limber pines gaining a foothold 

 after the fire. Observations at this point were at 5-day intervals. 

 No soil-moisture determinations were made. 



This station was equipped with : 



Maximum and minimum thermometers in shelter 5 feet above the ground 

 May 21, 1915, to October 1, 1916. 



Air thermograph, same location and period. 



Psychrometer. 



Anemometer 7 feet above ground. In addition to dial readings at 5-day 

 intervals, the velocity was observed during about an hour for each period from 

 May 21, 1915, to March 5, 1918. Even with this aid, however, it was impossible 

 to determine the 5-day movements with any certainty when high velocities 

 prevailed. 



Evaporimeter, wick Type 1, August 2G, 1915, to February 11, 1916. 



Evaporimeter, inner-cell, Type 2, April 1 to October 1, 1916. 



Eight-inch rain gage, May 21, 1915, to October 1, 1916. 



Soil thermometers, at depths of 1 and 2 feet in iron pipes, from Mav 21, 1915, 

 to October 1, 1916. 



Soil thermograph, ai 1 foot depth, September 1, 1915, to October 1. 1916. 



F-l',: Fremont north slope Douglas fir, half cut. -Elevation, 9;087 



U'c\ ; aspect, i\. 3° E.; -h>\)(\ 35 per cent. This station ;uul iho 

 following are counterparts of Station 7-8 in clear-cut and of St at ion 9 

 in uncut Douglas fir. Station I V represents conditions under a 

 half canopy of (lie taller trees of the original stand "with all under- 

 growth removed. The character of the cutting carried out. in 1913 

 w a- that known to foresters as tlie " shell erwood system." The 



