Most prescribed fire plans focus on reducing wildfire hazards with little consideration given to effects on wildlife populations and their habitats. To evaluate effectiveness of prescribed burning in reducing fuels and to assess effects of fuels reduction on wildlife, we began a large-scale study known as the Birds and Burns Network in 2002. In this paper we analyze changes in downed wood and forest structure (trees and snags) measured within one year after prescribed fire treatments that were completed in ponderosa pine (Pinus ponderosa) forests in Arizona and New Mexico (Southwest region), and Idaho and Washington (Northwest region). Apparent reductions in downed wood and trees were observed in both regions. However, statistically significant reductions of downed wood were found primarily in the Northwest (p < 0.001), whereas significant reductions of trees were reported only for the Southwest (p = 0.03). No significant post-treatment changes were detected in snag densities, although we observed a pattern of non-significant increases in all size classes. Additional fire treatments are likely needed to meet fuels reduction goals. Results of this study are intended to assist managers with developing scientifically sound and legally defensible prescribed fire projects that will reduce fuels and concurrently enhance wildlife habitat.