From the Summary ... 'Interpretation of underburning in mixed conifer/pinegrass community types of the Blue Mountains in eastern Oregon suggests that: surface fires occurred at an average of at least once every 10 years; ponderosa pine is being replaced by white fir or Douglas-fir; ponderosa pine stands did not develop according to the normal stand development concept; pine stands require control of stocking density to avoid stagnation; range grasses decrease with increasing tree cover as pine is replaced by fir regardless of livestock use, thereby complicating interpretation of range trend; pinegrass is capable of sustaining livestock use because of its development under periodic 100 percent utilization by fire; some plants, particularly shrubs, are dependent upon fire for their survival whereas other shrubs are killed by fire; soils in these plant communities have developed under periodic fire and should be considered brown forest instead of podzolic due largely to this fire influence and its encouragement of grass vegetation; and fire hazard is changing from light, flashy fuels under an open tree canopy to heavy fuels. Control of underburning in the mixed conifer-pinegrass community has created an increased fire hazard in a KNOWN FIRE ENVIRONMENT. We have changed from a fire resistant plant community to a fire susceptible plant community. We may not have a choice about burning -- only a choice of how to burn: prescribed fire or wildfire.'