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Herbaceous fuels drive fire behavior in grasslands and in mixed fuel complexes where grasses are a component of the surface fuels. In their “dead fuel” phase, herbaceous fuels constitute 1-hour fuels and contribute greatly to fire danger and fire spread. In their “live” phase, herbaceous fuels can serve as a heat source or sink depending on their fuel moisture. Therefore, grassland fuels are a fitting subject for study, especially considering the enormous land area over which they occur worldwide. Some of the biggest unknowns in fire danger/behavior modeling pertain to live and dead fuel loads, as well as live fuel moisture (not only what the values are but also how they change throughout the year). For those fire danger/behavior systems that are dynamic, fuel loads between the live herbaceous and 1-hour dead classes are shifted as a function of either manual observations (e.g., percent curing, percent greenness) or satellite observations. Live fuel moisture is often modeled by similar methods. Such systems largely have ignored the effect of surface weather conditions on fuels as well as the effect of soil conditions (e.g., directly measured soil moisture). During intensive biweekly field sampling of local plots from 2012 and 2013, we collected fuel bed data from tallgrass prairie with successional vegetation produced by fuel treatments consisting of spatially and temporally variable fire and grazing. Relationships will be investigated between the measured/calculated fuel bed variables and soil moisture measurements, weather data, and remotely sensed spectral reflectance data from a hand-held radiometer as well as from satellites. This paper will describe insights gained from these data and from associated studies relating soil moisture and weather data from the Oklahoma Mesonet to wildfire occurrence and size in Oklahoma from 2000 to 2012.