GENERAL REPORT. 7 



the nutritious bunch-grasses, though these do extend in magnificent growth 

 up into the open valleys and among the less dense timber to an altitude 

 of nearly 11,000 feet. 



From South Park to the New Mexican line we regularly found abun- 

 dance of this forage on the eastern slope of the main chains. In the beau- 

 tiful valley of the Conejos River, after striking the timbered region, we 

 found luxuriant bunch-grass covering the ground as thickly as it could 

 stand. In November it was still green about the roots, and was eagerly 

 eaten by our starved mules. Pinus ponderosa formed open clumps, and 

 under protection of these trees it attained what seemed to be its maximum 

 growth. 



From 9,500 to 10,500 feet the principal arboreous growth was made 

 up of Pinus contorta, Pinus ponderosa, Abies Mewziesii, and Abies sub- 

 alpina. Pseudotsuga Bouglasii seemed more at home at a somewhat less 

 elevation. Pinus ponderosa was frequently seen to extend in full size almost 

 to the verge of the timber-line, and often to attain its largest growth at an 

 elevation of 11,000 feet. 



In this belt (from 9,500 to 10,500 feet), Berberis Aquifolium formed a 

 conspicuous feature of the flora, especially in the more open woods. The 

 herbaceous vegetation of the same zone is well represented by Castilleia 

 pallida, Parnassia parviflora, Pedicularis Grcenlandica, Habenaria dilatata, 

 Polygonum Bistorta, TrifoUum dasyphyllum, Senecio triangularis, Gentiana 

 detonsa and acuta, with several species of Pentstemon. 



From 10,500 feet to timber-line (approximate estimate, 11,500 feet), a 

 change more or less marked occurs in the vegetation. This zone embraces 

 within its limits a greater diversity of soil, exposure, and local differences 

 of temperature than the one we have just described. There are open valleys 

 with perfect drainage, and hence dry soil ; and others so swampy that it is 

 almost impossible to ride over them; rocky slopes and deeply shaded 

 ravines, which are always damp from the spray of a mountain stream. 

 Hence it is not surprising that a more diversified flora should be found 

 here. Pinus flexilis, continuing over from the lower zone, now in this its 

 favorite altitude, becomes the predominant Conifer. It is subject to great 

 changes in its habit, and among these there is none more remarkable than 



