This proposal will map and measure the rates and timing of conifer invasion of grasslands at lower timberline elevations along the western slope of the Madison Range in Montana. Conifer invasion is a recent phenomenon related to overgrazing, range deterioration, fire suppression, and good conifer seed crops in years of above-average precipitation. Modelling and understanding the relationships between human land use and the physical causes of conifer invasion will increase our understanding of ecosystem dynamics generally, and human impacts on vegetational succession in alpine regions more specifically. The changes that will be modelled and explained by the investigators have major implication for species diversity in the region as well as for rangeland policy and managment.
