FOREST TYPES IX CENTRAL ROCKY MOUNTAINS. 21 



The station, of course, does not exactly represent the conditions of 



the forest. It is thought to be advisable to use the records as show- 

 ing the conditions at the upper limit of lodgepole growth, in contrast 

 with the more nearly optimum conditions of Nast, on the western 

 slope of Colorado, of Foxpark, on the eastern slope in Wyoming, and 

 oi Fraser, in an interior basin. 



M—l: Foothills western yellow pine. — Elevation, 7.200 feet: aspect, 

 easterly; slope, 3 to 4 per cent. This station is located at the Monu- 

 ment Nursery, 2 miles west of the railroad station of the same name, 

 and about 20 miles north of Colorado Springs. It may well be com- 

 pared with other stations in the Pikes Peak series. .It represents the 

 foothills type of yellow pine forest, this type being characterized by 

 scrub oak as a secondary cover, which appears to be able to drive 

 3'ellow pine to the rocky situations, poorer soils, and the banks of 

 eroding gulches. 



The station is scarcely more than 100 feet higher than the valley 

 of Monument Creek, which is devoid of forest growth. The pine 

 forest, however, appears on the first hills above the creek. Else- 

 where, under similar circumstances, the pine occurs at elevations 

 below 6.000 feet, along ravines and bluffs; hence this station site 

 represents the lower limit of pine growth only as determined by 

 local topography and soil. The present site of the station is on a flat, 

 east-west ridge or bench about 20 feet higher than the parallel gulch 

 just to the north. Prior to January, 1915, temperature and precipita- 

 tion records were obtained in this gulch, where cold-air drainage is 

 much more pronounced. 



The station is surrounded by oak brush. (See PL VIII, fig. 1.) In 

 this brush a few yellow pine seedlings of various ages are making 

 headway. The nearest mature pines stand 40 or 50 feet to the south 

 on an elevated part of the rid^e and do not shade the station. 



The soil is a very rocky mixture of granitic origin. In the first 

 foot the fragments of granite occupy only a small part of the space, 

 while at a depth of 2 or 3 feet the grayish sandy soil claims only obout 

 60 per cent of the space. The soil contains nearly equal parts of 

 gravel, sand, and finer material. It is evidently a transported soil 

 deposited here before the beginning of the secondary erosion, though 

 its coarse texture suggests glacial rather than water action. 



The following equipment has been in use in connection with the 

 daily observations since January, 1915: 



Maximum and minimum thermometers, in shelter, 5 feet above the ground. 



Air thermograph, until January 1, 1920. 



Psychromctcr, April 8, 1916, to June, 1919. 



Anemometer, on pole, 7 feet above the ground. This height gives some 

 freedom from the protection of the oak brush, most of which is 5 to 7 feet high. 



Evaporimeters, Tvpe 2, 5 feet above ground, April 3, 1916, to December 30, 

 1916. 



Evaporimeters, Type 4, 5 feet above ground, January 27, 1917, to date. 



Soil thermometers, at depths of 1 and 4 feet, in iron pipes. 



Soil well. Samples taken weekly during growing seasons from 1915 to- 191 s. 

 Sent by mail to Fremont Experiment Station, usually involving about two days 

 in transit before moist weight is taken. 



8-inch rain gage. 



N-l; Nast western slope lodgepole pine. — Elevation, 8,800 feet; 

 aspect, westerly. This station is situated on the Colorado Midland 

 Railroad between Hagermann Pass and Thomas ville, and lies only 

 a few miles west of the highest comb of the Rockies, on a slope 



