Bailey & Bailey: Woody Plants of National Parks 13 



Lodgepole pine {P'lnus contorta) forms extensive forests at the lower 

 elevations with ponderosa pine {Pmus ponderosa) occurring in the valleys. 

 Wax currant {Ribes cereum) is a common shrub in this forest while the dry 

 open slopes favor such species as big sagebrush (Artemisia tridentata), bitter- 

 brush (Pursbia tridentata), and Parry rabbitbrush {Chrysothamnus Parryi) . 

 Engelmann spruce {Picea Engelmanni) and alpine fir {Abies lasiocarpa) 

 predominate in the zone above and on up to timberline. Douglas fir (Pseudo- 

 isuga taxifo[:a) is found in scattered patches throughout these types and limber 

 pine {Pmus flexilis) is widespread, though not abundant. The only common 

 broadleaf tree is aspen {Popiilus tre>nuloid''s), which occurs mainly in the 

 zone above the ponderosa pine. Shrubby willows {Salix species) are abundant 

 along streams and in moist valley bottoms. 



Shrubs which may be found in the spruce-forest belt include Rocky Moun- 

 tain maple {Acer glabrum) , creeping hoUygrape {Berberis repens), grouse 

 whortleberry {Vacciniitm scoparium). Rocky Mountain whortleberry {Vac- 

 ciniiim oreophilum), and snowberry {Symphoricarpos albus) . Commonly 

 found in rocky canyons or openings in the forest are such species as cliffbush 

 {Janiesia americana), bush rockspiraea {Holodiscus discolor var. dumosa), 

 and boulder raspberry {Rubus deliciosus), and in the open upper part of 

 the forest, mountain common juniper {Junipems communis var. saxatilis), 

 and snowbrush ceanothus {Ceanothus velutinus) . 



Extensive areas of the park are covered with alpine meadows above the 

 limit of trees. These are characterized by wide expanses of grasslands dotted 

 with clumps of low willows and bog birch {Betula glandulosa) . In addition 

 to numerous showy-flowered herbs many depressed flowering shrubs are 

 found, including bush cinquefoil {Potentilla fruticosa) , Mount Washington 

 dryad {Dryas octopetala), mountain bog Kalmia {Kalmia polifolia var. micro- 

 phylla), and skyland willow {Salix petrophila) . 



Southwest Region 



The area designated as the Southwest Region is an extensive high plateau 

 drained by the Colorado River and commonly known as the Colorado Plateau. 

 Variously colored cliffs and canyons carved in soft sedimentary sandstones, 

 limestones, and. shales give a distinctive character to this country in which are 

 located four of our western national parks. 



Mesa Verde National Park 



Mesa Verde National Park in southwestern Colorado lies on a high 

 mesa which rises abruptly 2,000 feet above the valley on the north and slopes 

 gradually southward. Park Point, the highest point in the park at an eleva- 

 tion of 8,575 feet, is at the top of the steep escarpment forming the northern 

 boundary and overlooking the valley. Several streams arising at the northern 

 end cut this tilting tableland into nearly parallel ridges and valleys which 

 reach a depth of 1,000 to 2,000 feet along the southern boundary. Many 

 ruins of Pueblo cliff dwellings are found in the nearly perpendicular canyon 

 walls. 



