214 CUMAX FORMATIONS OF WESTERN NORTH AMERICA. 



Herba: 



Pteris aquilina. 

 Polystichuni munitum. 

 Aepidium rigidum. 

 Penttmon gracilentus. 

 PentstemoD deustus. 

 Pentatemon bridgcsii. 

 Pentotemon labrosus. 

 Fragaria virginiana. 

 Washingtonia nuda. 

 Monardclla odoratissima. 

 Adenocaulum bicolor. 

 Lupinus grayi. 

 Lupinus omatus. 

 Hoaackia decumbens neva- 

 densis. 



Hydrophyllum occidentale. 

 Lathynia sulphureus. 

 Trifolium breweri. 

 Castilleia parviflora. 

 Pedicularis semibarbata. 

 Achillea millefolium. 

 Erigeron breweri. 

 MicroBcris nutans. 

 Hieracium albiflorum. 

 Senecio lugens. 

 Crepis occidentalis. 

 Crepis intermedia. 

 Chaenactis douglasii. 

 Antennaria argentea. 



Kelloggia galioides. 

 Phacclia ramosissima. 

 Draperia aystyla. 

 Viola lobata. 

 Pirola picta. 

 Delphinium decorum. 

 Silene califomica. 

 Silene lemmonii. 

 Erysimum asperum. 

 Eriogonum umbellatum. 

 Iris hartwegii. 

 Corallorhiza multiflora. 

 Sarcodes sanguinea. 



THE COAST FOREST CLIMAX. 



THUJA-TSUGA FORMATION. 



Nature. The Coast climax of the Northwest is a coniferous forest of 

 unrivaled magnificence. The mature trees are very tall, 125 to 200 feet high 

 and 5 to 15 feet in diameter; or, in the case of Sequoia sempervirens, 300 feet 

 or more high and 10 to 20 feet in diameter. They form a dense canopy which 

 makes a deep shade, in which secondary trees find growth all but impossible. 

 In the mature forest, layers of shrubs and herbs are poorly developed or con- 

 sist of relatively few species. The layer of duflf and organic soil is deep, and 

 the conditions within the forest are almost ideal for germination and growth, 

 except for the low light intensity. The number of major dominants is prac- 

 tically the same as in the montane forest, with which the Coast climax shows 

 a closer relationship. The dominants are much more restricted in range, 

 however, especially from east to west. As a consequence, the cedar-hemlock 

 forest shows less differentiation, and it might well be regarded as composed 

 of a single association. The breadth and importance of the transition zone 

 between it and the montane forest, together with other reasons discussed later, 

 seem such as to warrant the recognition of two associations. 



Extent. As the name implies, the Coastal climax has its greatest develop- 

 ment along the Pacific coast. The main body of the formation stretches from 

 southern British Columbia to northern Cahfornia, but several of the major 

 dominants extend much farther northward as well as southward. The 

 northernmost in range is Picea sitchensis, which finds its boreal limit at Cook 

 Inlet and Kodiak Island, Alaska. Tsuga heterophylla and Chamaecyparis 

 nootkatensis extend nearly as far, reaching Prince William Sound, while 

 Thuja plicata is found in southern Alaska and Abies amabilis at the extreme 

 southern end. The most southerly range is that of Sequoia sempervirens, the 

 last outposts of which are found in the Santa Cruz and Santa Lucia Mountains 

 of California. This striking species is practically confined to this State, occur- 

 ring elsewhere in but few groves just across the Oregon line. Four other 

 major dominants are found with the redwood to Mendocino, Sonoma, and 

 Marin Counties. These are Tsuga heterophylla, Thuja plicata, Picea sitchensis, 

 and Abies grandis. While Pinus monticola, Pseudotsuga mucronata, and other 

 members of the transition association extend farther south, especially in the 

 Sierra Nevada, it is as dominants of the subalpine or of the montane forest. 



