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On grasslands, these fires limit encroachment by most woody trees and shrubs (Biodiversity Guidebook 1995). Late seral and climax grasslands and shrublands are typically restricted to droughty sites that occur at low elevations or on steep south-facing slopes or fire-prone areas. The Kamloops Land and Resource Management Plan (LRMP) has designated portions of the watershed as Critical Deer and Moose Winter Range (Speed and Henderson 1998).

The Grassland Ecosystem

Grassland communities currently face the greatest threats to their biodiversity (Harding and McCullum 1994). B.C. grasslands are unique in Canada because they are dominated by bunchgrass, bluebunch wheatgrass and many other plant species that occur only rarely east of the Canadian Rockies. Moreover, B.C.’s grasslands represent the northern limit of extensive bunchgrass vegetation in North America (Harding and McCullum 1994). Most of the grasslands in Canada have been eliminated primarily due to agricultural cultivation and livestock grazing. In the Southern Interior of B.C., fire suppression, urban development and associated outdoor recreational pursuits are all major factors contributing to the disappearance of grasslands. It should also be noted that in some instances agriculture and the responsible grazing of domestic livestock has contributed to the enhancement and preservation of grasslands. (e.g. Douglas Lake Ranch)

Fire in the Valley Ecosystem

Before European settlement, low elevation grasslands and open forests were more widespread throughout the Bunchgrass and Ponderosa Pine biogeoclimatic zones and drier elements of the Interior Douglas-fir biogeoclimatic zone. Prior to settlement, natural fire disturbances were fairly common. In addition, some of the open forests and grasslands were maintained by aboriginal use of fire. Recent human activities have altered fires regimes in much of the Deadman Valley. Several decades of fire exclusion has caused many Ponderosa pine and interior Douglas-fir stands to fill in with young conifers. This has resulted in fuel accumulations, increased probability of crown instead of surface fires, loss of understorey forage, and insect disease and damage.

There is also a change in forage quality. Native bunchgrasses associated with fire-maintained stands produce high protein levels during the growing season. In closed and ingrown stands, the lower-growing pinegrass predominates. It produces lower protein levels in the summer and does not retain its protein through the winter. Pine grass is also extremely unpalatable to domestic livestock therefore often not grazed unless there is absolutely no other available feed. According to valley residents, these patterns are evidenced in diminishing quality and quantity of grazing areas, the distribution and abundance of certain species of wildlife and culturally important vegetation (ie. berries and medicinal plants).