Culture and Ecology of Chaco Canyon and the San Juan Basin

Environment and Natural Resources 49CULTURALSEQUENCE.------r-H~'S T-OR-'C-' N-'V-AJO 7~ ~~~ n 7 i 7~ ~I' ~II j !;,.Ii iIFigure 2.7.Environmental reconstruction based on study of macrobotanical remains recovered frompack rat middens. (Taken from Betancourt and Van Devender 1981 :Figure 1.)to changes in the environment during the past 11,000years. Figure 2.7 summarizes the data, which wereinterpreted as follows:Late Pleistocene: The area probably was coveredby a subalpine forest consisting mainly of limberpine (Pinus cf. jlexilis) , Douglas-fir (Pseudotsugamenziesii), and spruce (Picea sp.).Early Holocene (or Paleoindian, 11, 000 to 9,000B.P.): Mixed conifer communities were dominated byDouglas-fir, Rocky Mountain juniper (Juniperusscopulorum), and limber pine. There was only oneexample of spruce. It was inferred that the plantcommunities in Chaco Canyon were relicts of anextensive Late Pleistocene forest dominated byDouglas-fir, limber pine, and spruce. The weather