xx 4 THE CONDOR I Vol. IV I refer to the dark primeval redwood forests, especially those a short distance back from the coast, which occupy rather broad flattish valleys. Besides the redwoods which 'stand' remarkably heavy are large Sitka spruces (Picea silchensis) western hemlocks (Tsuga helerofih. ylla), Pacific cedar (Thujafilicala), and north of the Klamath the Lawson cypress(Charn?ec. yfiaris lawsomaha), all tending to produce a forest of Canadian-like qualities. It is only in favored places that the sun is able to penetrate the heavy foliage of these conifers, and among the cool depths of the forest we encounter real Canadian conditions. The redwood tree itself is not diag- nostic, but the Sitka spruce, western hemlock and Pacific cedar while entering Transition--as we wodld expect from the nature of this zone--are all essentially Canadian trees, being common and characteristic in the Sitkan District. When fully develofied they may be taken as marking the limits of the Canadian on the coast of northern California. Stunted groves occur sometimes in the coastal areas I have indicated as Transition, and occasionally in these groves we encounter tiny isolated Canadian islands. Not infrequently such groves were once in the interior of the redwood forest, which has long since been removed. The presence of a small percent Douglas spruces in the heavy forests indicates Transition qual- ities. In this area I found no boreal plants which are not almost equally charact- eristic of the cooler Humid Transition. Acer circinalum Achlys trifih. ylla Berberis aquifolia Berberis netrosa Gallurn bareale (local Crescent City) Gaultheria shallon ]-/ipfiurus vulgaris onicera involucrata Ledurn glandulosurn (Crescent City) W[enziesia glabella Oxalis oregana Rubus fiarviJ7orus Rubus sfiectabilis Vacciniurn fiarvif oliurn Veratrurn californicurn Whififilea rnodesta Arctostafihylos uva-ursi is here purely maritime, as is Pinus contorta, and appar- ently, Abies grandis. It is not well to insist too strongly on their adequacy for tracing Canadian, tho they are all boreal types of great value. Several birds emphasize the presence of the Boreal rather decidedly. These are Bonasa urnbellus sabinei (also Transition), ?erisoreus obscurus, Merula rn. inqua and ?rxoreus ncevius. Such birds as Colurnba fasciata, Dryobates v. harrisi, Chcvtura vauxi, Contofius borealis, Cyanocitla s. carbonacea, Jonotrichia 1. nullalii, Olbiorchilus h. fiacificus, and Certhia/. occidentalis, tho ranging freely in to the Humid Transition are essentially Canadian in their nature--that is not Austral. Several distinctively boreal species of small mammals occur in the heavily forested belt. Perhaps none is more striking than the lemming-mouse (?henacornys albipes Mer- riam). To summarize. At present it seems that the Northwest Coast Boreal District, in California occupies only a very narrow and restricted belt in the form of dilute Canadian, south to the vicinity of Cape Mendocino. This belt comprises only the densest forests of redwood, Sitka spruce, western hemlock, Pacific cedar and Law- son cypress. All the other country including an open belt along the coast, the more open river valleys, mutilated districts, as well as the mountains immediately to the east of the redwoods belong to the Humid Transition. The Humid Transition still farther east merges into the Arid Transition or belt of the yellow and sugar pines. ( To be continued.)
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