Flora

There is a wide variety of vegetation types and plant communities found on Niwot Ridge, considering the relatively small area that it occupies. Subalpine forest can be found on the lower, gentler eastern slopes, whereas the higher, more rugged western portions of the ridge are dominated by nearly unvegetated surfaces. Subalpine meadows and patches of krummholz sometimes are found in the abrupt transition between forest and tundra.

The interactions among wind, snow, and high relief result in a mosaic of snow-free and snow-accumulation areas with consequent wide variability in the amount and timing of meltwater release. Summer precipitation is also highly variable, both temporally and spatially, usually arriving in brief convective storms. Thus, the moisture available to the tundra plants is very unevenly distributed.

The major research area is the Saddle, with its western half being a snow accumulation area (up to 10 m in some years) and its eastern half remaining free of snow for most of the winter. Thus, the Saddle is characterized by several quite different vegetation communities within a fairly small area. During the early 1970s, Pat Webber and Diane May used ordination techniques to broadly define six vegetation communities, or noda, on the Saddle: fellfield, dry meadow, moist meadow, shrub tundra, wet meadow, and snowbed.

Belowground allocation and processes may be particularly important in alpine vegetation, as evidenced by the high root:shoot ratio.

Some of the alpine plants characteristic of Niwot Ridge are:

Acomastylis rossii, Castilleja occidentalis, Dodecatheon pulchellum, Eritrichum aretioides, Hymenoxis grandiflora, Minuartia obtusiloba, Primula angustifolia, Primula parryii, Ranunculus adoneus, Phlox sibirica, Trifolium parryii

Fauna

Animal life inhabiting the Niwot Ridge area range from microarthropods to elk (Cervis canadensis).

The only year-round avian resident in the Colorado alpine is the white-tailed ptarmigan (Lagopus leucurus). Common summer residents include:
Water Pipit (Anthus spinoletta), Rosy Finch (Leucosticte spp.), Horned Lark (Eremophila alpestris), White-crowned Sparrow (Zonotrichia leucophrys)

Of the 32 species of mammals observed on Niwot Ridge, approximately 20 are herbivores, and of these 12 are small herbivores, ranging in size from mice and voles to marmots. The small mammal herbivore community at Niwot Ridge includes:
Deer Mouse (Peromyscus maniculatus), Bushy-tailed Woodrat (Neotoma cinerea), voles (Microtus longicaudus, M. montanusi, Phencomys intermedius), Least Chipmunk (Eutamius mimus), Golden-mantled Ground Squirrel (Spermophilus lateralis), Northern Pocket Gopher (Thomomys talpoides), Pika (Ochotona princeps), Yellow-bellied Marmot (Marmota flaviventris), Snowshoe Hare (Lepus americanus), Porcupine (Erithizon dorsatum)

Other small mammals that have been observed on Niwot Ridge include:

Badger (Taxidea taxus), weasels (Mustela spp.) The hare, porcupine, and badger are transients.

Sources of information on this page were:

Halfpenny, J.C., and C.H. Southwick. 1982. Small mammal herbivores of the Colorado alpine tundra. Pp 113-123 In: Halfpenny, J.C. (ed.). Ecological Studies in the Colorado Alpine. Institute of Arctic and Alpine Research Occasional Paper 37. 147 pp.

May, T.A. 1980. Animal ecology: Overview. Pp 430-435 In: Ives, J.D. (ed.). Geoecology of the Colorado Front Range: A Study of Alpine and Subalpine Environments. Westview Press: Boulder, CO. 484 pp.