Research and management in forests with altered fire regimes often focus on understanding and manipulating fuels. Fuel loads are difficult to measure because of their inherent variability, but a better understanding of fuel-bed characteristics can aid in evaluating potential fire behavior and effects. Overstory forest structure and composition, which are more readily measured than fuels, would be expected to influence fuel accumulation. Forest Service researchers used intensive tree and fuel measurements in a fire-excluded Sierra Nevada mixed conifer forest to assess relationships and build predictive models for several classes of surface fuel to overstory structure and composition. Overstory variables explained between 16 and 29 percent of the variation in fuel load. Greater canopy cover and white fir abundance were associated with greater total fuel loads, while greater pine abundance was associated with lower load of fine woody fuels and greater load of litter. Duff load was positively associated with total basal area and negatively associated with oak abundance. Knowledge of relationships contributing to within-stand variation in fuel loads can increase our understanding of fuel accumulation and improve our ability to anticipate fine-scale variability in fire behavior and effects in mixed species stands.