Grassland Region
Area, ha
Ecoprovince
Ecosections
Boreal and Taiga Plains
15,160
3,360
Boreal Plains
Taiga Plains
Peace Lowland
Halfway Plateau
Muskwa Plateau
7,720
6,285
Contents:
Grasslands along the Peace River valley and plateau surface. K. Vince
The grasslands in the Muskwa Foothills Ecosection of the Taiga Plains Ecoprovince cover an extensive lowland that has been cut into by many large rivers. Soils are developed on glacial deposits that vary from glacial till to thick sediments left when ice-damned lakes, such as Glacial Lake Peace, drained.
The grasslands regions of the Boreal and Taiga Plains are influenced by weather systems from both the Pacific and the Arctic. Winters are long and cold under the influence of Arctic weather systems and, while summer is the time when most rain falls on the plains, long sunny and hot conditions dry out the soils.
back to top
Grasslands are now restricted to the south-facing slopes, river terraces and uplands along the main river valleys. The grasslands of the rolling plains were ploughed under after the First World War finished in 1918. Livestock grazing has been extensive along the Peace River and the present composition of many plant communities may have been altered.
The Peace River valley is the most prominent feature of the Boreal and Taiga Plains Ecoprovince. It has carved its course from it’s headwaters in the northern Rocky Mountains to the Alberta border and on to the Athabasca River. The deep valley up river from Hudson’s Hope is now buried under the waters of Williston Lake behind the W.A.C. Bennett dam. Below Hudson’s Hope the spectacular valley has been carved through the layers of deposits that poured into the ancient Glacial Lake Peace as the ice melted after the last glaciation. In places these deposits are as much as 225 metres deep.
Most of the remaining grasslands communities in the Boreal and Taiga Plains Ecoprovince are found along the breaks of the Peace River valley where cultivation was difficult or impractical.
Ecosection
BEC Zones with grasslands1
Major2 grassland BEC Subzones and Variants
Kiskatinaw Plateau
Clear Hills
Boreal White and Black Spruce Zone
BWBSmw1: Peace Moist Warm Boreal White and Black Spruce Variant
BWBSmw2: Fort Nelson Moist Warm Boreal White and Black Spruce Variant
1 Click here to find out more about the Biogeoclimatic Ecosystems Classification (BEC) System : http://www.for.gov.bc.ca/hre/becweb/system/how/index.html
2 Over 3,000 hectares.
The grasslands of the Boreal and Taiga Plains, on the dry eastern side of the Northern Rocky Mountains, are part of the northern extension of the mixed grasslands of the prairies.
BWBSmw1: Peace Moist Warm Boreal White and Black Spruce Variant: 14,245 hectares
Slender wheatgrass, related to the southern bluebunch wheatgrass, is the dominant grass species. The most extensive grasslands occur in this variant. The most widespread grasslands community is wheatgrass-needlegrass that covers the rolling plateaus and south-facing slopes of the major river valleys between 750 and 1050 metres. Other characteristic species in this community include short-awned porcupine grass, june grass, blunt sedge, northern bedstraw, yarrow and veiny meadowrue.
The Wheatgrass-Sedge association is less extensive and is found on low, moist, flat areas. It has a much wider variety of plant species, especially grasses and sedges. Other characteristic species include awned sedge, prairie rose, and common snowberry. The rich layer of flowering plants includes sedges, northern bedstraw, fireweed and veiny meadowrue.
Needlegrass communities, which include porcupine grass, Columbia needlegrass and green needlegrass are restricted to the drier, steeper south-facing valley slopes and knolls . They compete with poplar vegetation.
A small area of grassland that occurs on steep slopes along the Prophet River at the southern end of the Muskwa Plateau. Species composition is probably similar to the grassland communities described above.
Other Grassland Communities
Other grassland communities include Prairie sagewort-Western wheatgrass that grows on heavy soils on steep slopes above the Peace River. The shrub-steppe communities have a mix of saskatoon, rose, western snowberry and trembling aspen and are found on steep, south-facing slopes of the Peace, Beatton and Halfway Rivers.
Physiography of grasslands along the Halfway River. K. Vince
Many grasslands communities found in the Boreal and Taiga Plains share characteristics with other grassland communities further south in the prairies of Alberta. Some plants are at the most northern extent of their range, such as the plains reedgrass. Green needlegrass is unique to the Taiga Plains Ecoprovince but is common on central Alberta’s parklands. Other species occur throughout circumpolar regions and probably originate from arctic regions.
Slender Wheatgrass Slender Wheatgrass (Elymus trachycaulus)
Slender Wheatgrass
The position of the Boreal and Taiga Plains ecoprovinces on the east side of the Rocky Mountains and the rich variety of grassland habitats gives rise to a number of wildlife species not found elsewhere in British Columbia.
The Boreal Ecoprovince is home to the boreal chorus frog, which is unique to this region, while the only reptile species is the infrequently seen common garter snake. Many bird species that occur in the wider Alberta Plateau area occur only in this region in British Columbia. Canada warbler, MacGillivray’s warbler and orange-crowned warbler forage in grassland edges such as riparian areas. Three other grasslands birds, the sharp-tailed grouse, upland sandpiper and Eastern phoebe, are most abundant in this region of the province.
Three large mammals, the Stone sheep, dall sheep and grizzly bear use the grasslands for all or part of their needs. The wood bison has been reintroduced in three areas where they forage on grasses, sedges and various shrubby species.
Check the list of wildlife viewing sites publications.
Red- and Blue-listed grassland elements in the Boreal and Taiga Plains:
Element
Red List*
Blue List**
Vascular Plants
Plant Communities
Insects
Reptiles and Amphibians
Birds
Mammals
Total Elements
16
2
1
0
5
3
27
14
8
41
*Red list: List of ecological communities, and indigenous species and subspecies that are extirpated, endangered or threatened in British Columbia.
**Blue list: List of ecological communities, and indigenous species and subspecies of special concern (formerly vulnerable) in British Columbia.
The large number of listed plant species in the Boreal and Taiga Plains probably reflects the fact that these north grasslands are an extension of both the prairie grasslands and the southern extension of Arctic species. Fennel-leaved desert-parsley, long-leaved mugwort and Nuttall’s orache are three species common further south in Alberta, but red-listed in BC. Similarly with prairie buttercup and slender penstemon.
Three blue-listed large mammals can be found on the grasslands at all seasons: Dall sheep, Stone Sheep and Grizzly Bear. The red-listed Wood Bison has been re-introduced to the Pink mountain area, and the Upper Halfway and Sikanni Chief valleys. Some of the red-and blue-listed bird species include gyrfalcon, short-eared owl, Smith’s longspur, bobolink and Western grebe.
Blue-listed in BC
Pike’s swallowtail (formerly Baird’s swallowtail) is found flying in the dry grasslands on the banks of the Peace River west of the Alberta border from May to July. At 6.9 cm wide this yellow butterfly with the characteristic black markings of the swallowtail is larger and a brighter yellow than its southern grasslands cousins. It also has a distinguishing characteristic mark in the dorsal hindwing. It prefers to feed on tarragon plants and lays single, round eggs on the leaves. All stages of the immature butterfly may be found moving around on the plants. The pupa hangs below a branch.
Pike’s (formerly Baird’s) swallowtail: Peace River at the Clayhurst Bridge, 21 June 2006. © Cris Guppy
Pike's (formerly Baird's) swallowtail: Eggs, 21 June 2006. © Cris Guppy
For more information on species at risk in BC, visit our SAR page.
For definitions of technical terms, please see the GLOSSARY.
Print This Page