ecodomains are then divided into ecodivisions which delineate areas of broad climatic and physiographic uniformity. Next, the ecodivisions are divided into ecoprovinces which consider climate, oceanography, relief and regional landforms. The ecoprovinces are then divided into ecoregions which consider major physiographic and minor macroclimatic or oceanographic variations. Finally, the ecoregions are divided into ecosections for minor physiographic and macroclimatic or oceanographic variations. Overall, B.C. is divided into 4 large ecodomain areas which are progressively divided down into 114 small ecosections. Biogeoclimatic Zones of British Columbia The British Columbia Ministry of Forests and Range subdivides the province's ecoregions into a system of biogeoclimatic zones: Coastal Western Hemlock Zone: Wet, mossy, dense temperate rain forests of Western Hemlock, Western Redcedar, Pacific Silver (Amabilis) Fir, Yellow Cedar, Coast Douglas-fir, Grand Fir, Sitka Spruce, and Western White Pine, Bigleaf Maple, Red Alder, sword fern, devil's club, and red huckleberry predominate on the west coast of Vancouver Island, the west coast of the mainland north of the Fraser River delta to north of Prince Rupert, farther inland along the Fraser and Skeena River Valleys, and on Haida Gwaii. This zone was the original focus of British Columbia's forest industry; and most of the trees have been harvested at least once. There has been much effort (some successful) to protect the remaining old growth forest from logging. Coast Douglas-fir Zone: A drier region of temperate forest, this is the smallest and most heavily populated biome of the province. It encompasses the southern and most of the eastern coastal fringe of Vancouver Island, the Fraser River delta, the Gulf Islands, and parts of the Sunshine Coast. Trees unique to this area include the Arbutus, Garry oak, and manzanita. Interior Douglas-fir–Montane–Ponderosa Pine–Bunchgrass Zones: The dry valleys and plateaus of BC's southern interior, stretching from the lower reaches of the Chilcotin Plateau, across the southern Cariboo, and south through the Okanagan. A separate, isolated region exists in the East Kootenay. This region encompasses the Fraser Canyon, the lower Thompson River, and the Nicola and Similkameen watersheds. It is characterised by treeless bunchgrass steppes, sagebrush scrub, and open forests of Ponderosa Pine, Rocky Mountain Douglas-fir, trembling aspen, Lodgepole Pine, and Western Larch. Much of the area is used for timber harvesting, ranching, and orchard-growing. The winters are cold and dry, and the summers are hot and drier. Interior Redcedar-Western Hemlock Zone: An interior wetbelt, similar to the Coastal Western Hemlock