\ 
562 Part IV. Chapter 3. 
Hippiana, Eriogonum umbellatum, E. ovalifolium, Arenarıa congesta, Castil- 
leia miniata, and as the chief constituent Artemisia tridentata and in 
scattered bunches Bigelovia. Open xerophytic parks exist between streams 
in these mountains where are found Campanula rotundifolia, Cnicus Drum- 
mondi, Arenaria congesta, Potentilla Hippiana and Artemisia tridentata. 
Rock Outcrops. There is little or no vegetation gg the outerops of rock oceur in the 
Arge Valley, The Erneut rock has a covering of lichens of the foliaceous sort, 
he accumulation of more soil such a fruticose Hemer: as Cladonia rangiferina var, sylvatica 
appears accompanied by Selägibeiie: densa, Sedum rege Heuchera parvifolia. The rock 
erevices however filled with soil are favorable for the ‚growth Prunus demissa, Amelanchier 
alnifolia, nn nana (= ]. sibirica), Campanula aka; Arctostaphylos uva-ursi. If the 
a large body of water Juniperus scopulorum is found and with it Pseudotsuga 
Doigtesit "and "Pins ponderosa 2). 
5. Alpine Formations. 
These extend properly above timber-line which in the Park Mountains 
may be fixed approximately at an elevation between 11,000 and 12,000 feet 
(3350-3660 m). It is a rock desert and: steppe belt. Mat-forming plants and 
deep-rooted perennials are common. In Colorado the alpine flora at 12,000 feet, 
or above, according to COCKERELL?) comprises 386 species, 48 of which extend 
to the old world. Boulder fields are practically destitute of vegetation excepft 
lichens. Sedges and grasses are numerous in species, but seldom form a dense 
sod, being mixed with various flowering herbs. Dwarf willows occur often form- 
ing a dense scrub over large areas, but there are no other woody plants. — None 
of the peaks are glaciated, although snow banks persist in protected places 
well through the summer months. The trees which reach timber-line in 
the Rocky Mountains are Adies subalpina, Pinus albicaulis, mountain hemlock Ri; 
Tsuga Pattoniana, Pinus aristata, Pinus flerilis, Picea Engelmanni (Uintah 
Mountains). Br: 
Alpine meadow Formation. The facies of this formation in Colorado’) 
is due to Carer rupestris, Carex filifolia, Sieversia grandiflora, Fesia 
en var. nana. & 
occidentalis, Polemonium confertum, Campanula uniflora, Trifolium 
As secondary species exist Pedicularis Parryi, Carex Penis Draba streptocarpa, D. aure 
ovina var, caespitosum. Later in the season the facies changes somewhat, then Deschampsia 
caespitosa var, alpina, Polygonum viviparum prevail with the following herbs; Phleum alpi 
on coryphocolum, Trisetum ee, Gentiana tenella, Agoseris (Troximon) aurantiaca, ir 
SERIEN, 
1} WHITFORD: loc. eit. p. 
2) The Alpine Flora of Color: American Naturalist XL: 861—873; also COOPER, w.S 
Alpine Vegetation in the Viecinity of Long’s Peak, Colorado: The Botanical Gazette XLV: a 3 
3) CLEMENTS, FREDERIC E,: Formation and Succession Herbaria. University of Nebe az 
Studies IV, No. 4, Oct. 1904. 
