A Wisconsin alluvial deposit with surface features similar to those of rubble streams, rock glaciers, or debris flows occurs in Tom Mays Park Canyon in the northern Franklin Mountains between 5,100 and 5,900 ft elev at lat 31°53′ N. This was too low, at this latitude, to permit formation of interstitial ice. The deposits may have resulted from major flash-flood deposition of rock-fall talus-slope accumulations, resulting from intense frost action, in a regimen originally suited to the transport of products of a normally arid, frost-free climate. This boulder flow is an aggregate of rhyolite which was uniquely responsive to an ephemeral Wisconsin frosty climate. Maximum erosion in this canyon since middle Wisconsin is about 40 ft in stream alluvium and nil on talus slopes. The term boulder flow is proposed for a rock fragment wet flow.