Abstract for M028

Great Plains Floodplain Forest
Forêts alluviales des Grandes Plaines

M028 describes North American Great Plains floodplain forests and woodlands. The Canadian expression of this vegetation occurs on river floodplains throughout the Great Plains region in southern Alberta, Saskatchewan and Manitoba. In Canada, floodplain forests are dominated by cold-deciduous broad-leaved tree species, including eastern cottonwood (Populus deltoides ssp. monilifera), Manitoba maple (Acer negundo) and red ash (Fraxinus pennsylvanica), with other species locally important. Dense understory vegetation comprises broad-leaved shrubs, forbs and graminoids. Common species include red-osier dogwood (Cornus stolonifera), willows (Salix spp.), cranberry viburnum (Viburnum opulus), saskatoon (Amelanchier alnifolia), chokecherry (Prunus virginiana), wolf-willow (Elaeagnus commutata), silver buffaloberry (Shepherdia argentea), bluejoint reedgrass (Calamagrostis canadensis), slender wildrye (Elymus trachycaulus), fowl bluegrass (Poa palustris), Canada goldenrod (Solidago canadensis), star-flowered false Solomon's seal (Maianthemum stellatum), wild licorice (Glycyrrhiza lepidota), poison ivy (Toxicodendron radicans), stinging nettle (Urtica dioica), Maryland sanicle (Sanicula marilandica) and American cow parsnip (Heracleum maximum).

In Canada, M028 occurs in a dry to subhumid continental temperate climate with cold winters and warm summers. Mean annual temperatures average approximately 3˚C, and precipitation varies from approximately 300 to 500 mm. Sites supporting stands of M028 are characterized by extra moisture as a result of high water tables, run-off from valley slopes and/or stream overflow. Sediment and dissolved materials carried by inflowing water can make floodplain sites relatively nutrient rich. Soils are usually Regosols, lacking horizon development because of ongoing deposition of alluvium.