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UNIVERSITY OF COLORADO STUDIES 



Aconitum insigne Greene 



Actaea viridiflora Greene 



Halerpestes cymbalaria (Pursh) Greene 



Ranunculus macounii Britton 



Thalidrum Jendleri Engelm. 



Arabis drummondii Gray 



Arabis oxyphylla Greene 



Lepidium crandallii Rydb. 



Sophia incisa (Engelm.) Greene 



Stanleya arcuata Rydb. 



Thelypodium gracilipes (A. Gray) S. Wats. 



Capnoides aureum (Willd.) Kuntze 



Ribes pumilum Nutt. 



Cercocarpus parvijolius Nutt. 



Geum strictum Ait. 



Potentilla diversifolia Lehm. 



Rosa nutkana Presl. 



Amelanchier oreophila A. Nels. 



Crataegus saligna Greene 



Crataegus cerronis A. Nels. 



Prunus melanocarpa (A. Nels.) Rydb. 



Prunus pennsylvanica L. f. 



Vicia americana Mulil. 



Geranium fremontii A. Gray 



Geranium richardsonii Fish. & Traut. 



Rhus trilobata (Nutt.) Small 



Acer glabrum Torr. 



Vitis vulpina L. 



Sidalcea Candida A. Gray 



Sidalcea neo-mexicana A. Gray 



Malvastrum coccineum (Pursh) A. Gray 

 Chamanaerion angustijolium (L.) Scop 

 Epilobium adenocaulon Hasskn. 

 Epilobium paniculatum Nutt. 

 Gayophytum ramosissimum T. & G. 

 Onogra strigosa Rydb. 

 Angelica ampla A. Nels. 

 Cicuta occidentalis Greene 

 Washingtonia obtusa C. & R. 

 V actinium oreophila Rydb. 

 Androsace subulijera (A. Gray) Rydb. 

 Asclepias speciosa Torr. 

 Gilia aggregata (Pursh) Spreng. 

 Polemonium foliosissimum A. Gray 

 Phacelia glandulosa Nutt. 

 Agastache urticijolia (Benth.) Kuntze 

 Mentha penardi (Brig.) Rydb. 

 Castilleja linariaefolia Benth. 

 Orthocarpus luteus Nutt. 

 Pentstemon strictus Benth. 

 Pentstemon unilateralis Rydb. 

 Galium asperrimum Gray 

 Lonicera involucrata Banks. 

 Symphoricarpos pauciflorus (Robbins) Brit- 

 ton 

 Gymnolomia multiflora (Nutt.) B. & H. 

 Pyrrocoma crocea (Gray) Greene 

 Rudbeckia laciniata L. 

 Senecio admirabilis Greene 

 Solidago canadensis L. 



Sage-brush formation. 1 — One who passes from the eastern to the 

 western slope of the Rocky Mountains in Colorado cannot fail to be 

 struck with the great difference between the vegetation of the great 

 plains and of level areas in the western part of the state. The plains of 

 eastern Colorado are grass-covered; sage-brush is dominant on level 

 stretches of western Colorado. This sage {Artemisia tridentata) is most 

 abundant on flat expanses back from streams; it occurs on flat areas 

 generally, reaching its greatest development in deep, fine-grained soil. 

 As slopes become steeper and more stony, with a consequent decrease 

 in soil depth, sage-brush gives away to pinyon pine, cedar and shrubs 



1 Pool, R. J., "Histological Studies in the Artemesia Formation," Univ. of Neb. Stud., Vol. VIII, pp. 

 1-28, Oct., 1008. 



