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While most species in the Upper Sonoran Desert, particularly the saguaro/paloverde community, are adapted to varying intensities of fire, rapid changes in the fire regime during the last half of this century not only make earlier fire regimes moot, but place the broad scale sustainability of this community in peril. Case studies show new fire regimes have fire intensities beyond the survivability of the two keystone species saguaro and paloverde. When killed by wildfires these two species tend to decompose rapidly, masking the additive nature of the widespread loss of this community across large portions of the Upper Sonoran Desert. Once in place the new fire regime is perpetuated, making permanent re-establishment of these species impossible. The change in the fire regime comes primarily from two sources, an increased number of road miles (including road landscaping and road traffic), and a rapid expansion of non-native annual grasses. Long-term survival of remaining saguaro/paloverde communities and successful re-establishment of these keystone species where they have been eliminated is contingent upon reduction of grass fuels and breaking the connectivity between fire ignition sources and the desert community. Livestock have played a key role in the spread of the annual grasses, but can also play a beneficial role in reducing their impact if managed in a manner that doesn't impede the replenishing of the native forbs and seed bank after fire events.