Okanagan dry forests is a

temperate coniferous forest Temperate coniferous forest is a terrestrial biome defined by the World Wide Fund for Nature. Temperate coniferous forests are found predominantly in areas with warm summers and cool winters, and vary in their kinds of plant life. In some, needlel ...

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...

in the

Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, as defined by the

World Wildlife Fund The World Wide Fund for Nature Inc. (WWF) is an international non-governmental organization founded in 1961 that works in the field of wilderness preservation and the reduction of human impact on the environment. It was formerly named the Wo ...

(WWF) categorization system. It is closely associated with the

Okanagan The Okanagan ( ), also known as the Okanagan Valley and sometimes as the Okanagan Country, is a region in the Canadian province of British Columbia defined by the basin of Okanagan Lake and the Canadian portion of the Okanagan River. It is part ...

region of

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

and

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

. Only 20% of the ecosystem is still intact, and continues to be under threat for preservation due to land clearing and urban expansion, alongside the increasing threats of fire and

extreme weather Extreme weather or extreme climate events includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Often, extreme events are based on a locat ...

due to climate change.

Geography

This ecoregion occupies the south-central interior of

and adjacent

state between the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...

to the east and the

Pacific Ranges , photo = Mount Garibaldi (50997016501).jpg , photo_size = 280px , photo_caption = Mount Garibaldi massif as seen from Squamish , map = , map_image = South BC-NW USA-relief PacificRanges.png , m ...

to the west. It is composed of gently rolling hills of Tertiary

sediments Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand a ...

and

volcanic rocks Volcanic rock (often shortened to volcanics in scientific contexts) is a Rock (geology), rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of Volcano, volcanic origin. Like all rock types, ...

between 1220-1525 metres (4000-5000 ft) in elevation. These hills are incised by numerous bodies of water such as the

Columbia River The Columbia River (Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, C ...

Thompson River The Thompson River is the largest tributary of the Fraser River, flowing through the south-central portion of British Columbia, Canada. The Thompson River has two main branches, the South Thompson River and the North Thompson River. The river ...

, and

Okanagan Lake Okanagan Lake ( oka, kɬúsx̌nítkw) is a lake in the Okanagan Valley of British Columbia, Canada. The lake is long, between wide, and has a surface area of 348 km2 (135 sq. mi.). Hydrography Okanagan Lake is called a fjord lake as i ...

Climate

The ecoregion has a

cold semi-arid climate A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-ar ...

(

Köppen Köppen is a German surname. Notable people with the surname include: * Bernd Köppen (born 1951), German pianist and composer * Carl Köppen (1833-1907), German military advisor in Meiji era Japan * Edlef Köppen (1893–1939), German author and ...

''BSk'') with very warm to hot, dry summers and moderately cool winters with little snowfall. A strong elevational gradient in precipitation occurs, ranging from 250 mm (9.8 in) to over 1000 mm (39.4 in) per year. On average, precipitation is in the range of 400 mm (15.75 in) on the plateaus. The mean annual temperature is around 7°C (44.6°F), mean summer temperature ranges from 15°C (59°F) to 16.5°C (61.7°F), and mean winter temperature is around -2.5°C (27.5°F). The driest place in Canada outside of the

Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...

is in the

Kamloops Kamloops ( ) is a city in south-central British Columbia, Canada, at the confluence of the South flowing North Thompson River and the West flowing Thompson River, east of Kamloops Lake. It is located in the Thompson-Nicola Regional District, w ...

region of

Thompson Country Thompson Country, also referred to as The Thompson and sometimes as the Thompson Valley and historically known as the Couteau Country or Couteau District, is a historic geographic region of the Southern Interior of British Columbia, more or less de ...

, which falls within the northwestern bounds of this ecoregion. The Okanagan dry forests ecoregion is sometimes referred to as a

desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...

due to its hot, dry climate relative to the rest of Canada. However, it and the neighbouring Columbia Plateau ecoregion near

Osoyoos Osoyoos (, ) is the southernmost town in the Okanagan Valley in British Columbia between Penticton and Omak. The town is north of the United States border with Washington state and is adjacent to the Osoyoos Indian reserve. The origin of the na ...

are

semi-arid A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-ar ...

ecoregions and are not true deserts.

Ecology

Flora

Looking Eastward over the Southern Okanagan Valley on a Spring Afternoon

Vegetative cover in this region encompasses forests and grasslands that change in character with increasing altitude. Lower elevations contain communities of

ponderosa pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the ...

bluebunch wheatgrass ''Pseudoroegneria spicata'' is a species of grass known by the common name bluebunch wheatgrass. This native western North American perennial bunchgrass is also known by the scientific synonyms ''Elymus spicatus'' and ''Agropyron spicatum''. The g ...

, blue grass, June-grass, and Great Basin sagebrush. Mid-slope elevations are home to communities of

Douglas-fir The Douglas fir (''Pseudotsuga menziesii'') is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three va ...

and

pinegrass ''Calamagrostis rubescens'' is a species of grass known by the common name pinegrass. Distribution It is native to western North America, including Canada from British Columbia to Manitoba and the United States from California to Colorado. It ca ...

. Higher elevations are home to communities

lodgepole pine ''Pinus contorta'', with the common names lodgepole pine and shore pine, and also known as twisted pine, and contorta pine, is a common tree in western North America. It is common near the ocean shore and in dry montane forests to the subalpine, ...

quaking aspen ''Populus tremuloides'' is a deciduous tree native to cooler areas of North America, one of several species referred to by the common name aspen. It is commonly called quaking aspen, trembling aspen, American aspen, mountain or golden aspen, tr ...

white spruce White spruce is a common name for several species of spruce (''Picea'') and may refer to: * ''Picea glauca'', native to most of Canada and Alaska with limited populations in the northeastern United States * ''Picea engelmannii'', native to the Ro ...

, and Douglas-fir. The southernmost portion of the ecoregion within Canada features a unique antelope brush plant community.

Fauna

Mammals in this region include Columbian ground squirrels (''Urocitellus columbianus''),

bighorn sheep The bighorn sheep (''Ovis canadensis'') is a species of sheep native to North America. It is named for its large horns. A pair of horns might weigh up to ; the sheep typically weigh up to . Recent genetic testing indicates three distinct subspec ...

(''Ovis canadensis''),

white-tailed deer The white-tailed deer (''Odocoileus virginianus''), also known as the whitetail or Virginia deer, is a medium-sized deer native to North America, Central America, and South America as far south as Peru and Bolivia. It has also been introduced t ...

(''Odocoileus virginianus''),

mountain goats The mountain goat (''Oreamnos americanus''), also known as the Rocky Mountain goat, is a hoofed mammal endemic to mountainous areas of western North America. A subalpine to alpine species, it is a sure-footed climber commonly seen on cliffs and ...

(''Oreamnos americanus''), American red squirrels (''Tamiasciurus hudsonicus''),

moose The moose (in North America) or elk (in Eurasia) (''Alces alces'') is a member of the New World deer subfamily and is the only species in the genus ''Alces''. It is the largest and heaviest extant species in the deer family. Most adult mal ...

(''Alces alces''),

yellow-bellied marmots The yellow-bellied marmot (''Marmota flaviventris''), also known as the rock chuck, is a large, stout-bodied ground squirrel in the marmot genus. It is one of fourteen species of marmots, and is native to mountainous regions of southwestern Canad ...

(''Marmota flaviventris''), and

wapiti The elk (''Cervus canadensis''), also known as the wapiti, is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. The common ...

(''Cervis canadensis''). The population also boasts a large population of

mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...

(''Odocoileus hermionus'') and

American black bears The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black be ...

(''Ursus americanus'').

Threats and preservation

Approximately 20% of the Okanagan dry forests remains intact, with most parts having been heavily altered due to clearing of land for agricultural production. Growing urban expansion also threatens this ecoregion, most notably around the cities of

Kelowna Kelowna ( ) is a city on Okanagan Lake in the Okanagan Valley in the southern interior of British Columbia, Canada. It serves as the head office of the Regional District of Central Okanagan. The name Kelowna derives from the Okanagan word ''ki� ...

, and

Spokane Spokane ( ) is the largest city and county seat of Spokane County, Washington, United States. It is in eastern Washington, along the Spokane River, adjacent to the Selkirk Mountains, and west of the Rocky Mountain foothills, south of the Ca ...

. Connectivity between grasslands for wildlife is heavily impaired by the development of lowland valleys. Human-caused

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

threatens to increase the frequency and intensity of

drought A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...

s and

wildfire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...

s in this ecoregion. Wildfires of note include the 2003 Okanagan Mountain Park fire, 2009 West Kelowna wildfires, and

2017 British Columbia wildfires On July 6, 2017, a two-hectare wildfire began west of 100 Mile House, British Columbia, Canada marking the beginning of the record-breaking 2017 wildfire season in British Columbia. On July 7, 56 new fires started throughout British Columbia (BC) ...

Protected areas

Some of the largest protected areas of this ecoregion include: * Arrowstone Provincial Park *

Bonaparte Provincial Park Bonaparte Provincial Park is an 11,811 hectare provincial park in British Columbia, Canada. It is located within the Bonaparte Plateau. History The park was established April 30, 1996 under the Kamloops Land and Resource Management Plan (LRM ...

Colville National Forest The Colville National Forest is a U.S. National Forest located in northeastern Washington state. It is bordered on the west by the Okanogan–Wenatchee National Forest and the Kaniksu National Forest to the east. The forest also borders Little Pe ...

Lac du Bois Grasslands Protected Area Lac du Bois Grasslands Protected Area is a protected area located north of Kamloops in British Columbia, Canada. The protected area was established by BC Parks on 30 April 1996 to protect a unique mixed forest-grassland ecosystem overlooking the ...

Okanagan Mountain Provincial Park Okanagan Mountain Provincial Park is a provincial park within the Okanagan-Similkameen Regional District of British Columbia, Canada, focused on the mountain of the same name and located on the east side of Okanagan Lake, opposite Peachland and ...

Riverside State Park Riverside State Park is a Washington state park located northwest of Spokane in the community of Nine Mile Falls. The park protects of Okanagan dry forest along the Spokane and Little Spokane rivers. It is the second largest state park in Wa ...

* White Lake Grasslands Protected Area

References

External links

* {{coord missing, Washington Ecozones and ecoregions of British Columbia Forests of British Columbia Forests of Washington (state) Nearctic ecoregions Temperate coniferous forests