Loadings of downed woody fuels in pine-oak forests of the Madrean Province are heavier on sites in southeastern Arizona with low fire frequencies and lower on sites in northeastern Sonora, Mexico, with high fire frequen- cies. Low fire frequencies in southeastern Arizona are attrib- uted largely to past land uses and the fire suppression policies of land management agencies in the United States. Ecologists and land managers interested in reintroducing fire into these forests to reduce fuel loadings and meet other land management objectives could use information about fuel buildups in their planning efforts. Quantifying these fuel loadings could also be useful in improving fire behavior models for the forests. 1999). Incomplete knowledge of wild-land fuel condi- tions, however, often constrains successful reintroduc- tions of fire. Quantifying fuel buildups under different fire frequencies and severities could provide useful information on fire regimes that might be prescribed in the reintroduction efforts. We discuss the effects of contrasting fire frequencies on fuel loadings in the pine-oak forests of the Madrean Province in the South- western United States and Northwestern Mexico