Camp Bowie (marked by white star) is located 
                    on the southeastern edge of the Rolling Plains, just north 
                    of the Llano Uplift, or Central Mineral region, of the Edwards 
                    Plateau. Map courtesy of Texas Parks and Wildlife Department. 
                    Click for more detail and map key.
                     Click images to enlarge 
                   
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                  The Camp Bowie project area encompasses 
                    several different vegetation zones. Map courtesy CAR- UTSA. 
                    Click for more detail and map key. 
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            The area that is now called Camp Bowie lies within 
              the Rolling Plains physiographic region. Its gently rolling hills 
              are cut by seasonally active steams and are dotted with stands of 
              oak, juniper, mesquite, pecan and elm trees along with grasses and 
              cacti. But the landscape we see today may scarcely resemble what 
              hunters and gatherers saw in the prehistoric past, prior to the 
              17th century (1600s). 
            Over the past 10,000 years, the vegetation of the 
              Camp Bowie area shifted between grasslands and woodlands as the 
              climate fluctuated between dry and moist periods. Brown County is 
              in a transitional climatic zone between the semi-arid western half 
              of Texas and the increasingly humid eastern Texas. Climatic shifts 
              change the dominate vegetation patterns and food supply and, in 
              turn, the availability and density of animals and birds. Prehistoric 
              hunters and gatherers would have adapted to the changing resources 
              as well. 
             Reconstructing the past environment is important 
              to the understanding of why people camped in particular areas and 
              what resources they may have been using. Understanding these questions 
              helps us to better understand why burned rock middens are so common 
              in the Camp Bowie region. 
            Using data such as fossil pollen from bogs and dry 
              caves and animal bones from archeological sites, scientists have 
              been able to reconstruct past environments in some areas. Preserved 
              pollen from certain species of grass or trees helps indicate whether 
              a prairie or a woodland was present at various times in the past. 
              Finding bones of animals such as bisonwhich inhabit grasslandsor 
              certain species of snailssome of which thrive in aquatic settings, 
              others in more arid settingsprovides another line of evidence 
              to past environmental conditions.  
            From roughly 18,000 to 10,000 years ago, Central Texas 
              began to change from generally cool, moist conditions to a warmer 
              and drier environment. This period, termed the Late Pleistocene 
              era, was followed by a moderately moist period from about 8,000 
              to 10,000 years ago (the Early Holocene period). The Middle Holocene 
              (4,000 to 8,000 years ago) was generally warm and/or dry, with a 
              brief moist (mesic) interlude sometime between 5,000 and 6,000 years 
              ago. By Late Holocene times about 4,000 years ago, the climate shifted 
              back to wetter conditions similar to the modern climate. These long-term 
              generalizations are, of course, just that; short-term fluctuations, 
              such as multi-year droughts, would have sometimes caused drastic 
              changes in how people used the landscape. 
            Several types of evidence hint at a dryer period between 
              about 750 to 1,500 years ago, while a more mesic interval is suggested 
              for the last 750 to 800 years. While all of the different data may 
              not be in agreement, it is clear that the past environment was not 
              static, but fluctuated between warmer, drier and cooler, moister 
              conditions.  
            For the Camp Bowie area, the full impact of long-term 
              climatic changes on the plant and animal communities isfor 
              the most partunknown. More recent changes, largely due to 
              human intervention, are more noticeable. These include an historic 
              increase in woody species, especially juniper/cedar and mesquite, 
              caused by the cessation of range fires and severe overgrazing by 
              livestock in the late 19th and early 20th centuries, the subsequent 
              clearing of wooded areas, the pumping of water for irrigation that 
              has lowered water tables, and the impacts of military training. 
              
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                  Rains bring seasonal streams in the Camp 
                    Bowie area to life. Shown here is the Devils River, a tributary 
                    of Pecan Bayou and part of the Colorado River drainage system. 
                    (Note that this small "river" in Brown County is 
                    not the same as the far larger Devil's River in southwest 
                    Texas.)   | 
               
              
                  
The Camp Bowie landscape 
      today probably looks quite different from how it appeared in prehistoric 
      times. Juniper (cedar) and mesquite, the dominate species today, were less 
      common (but still present) prior to the late 19th century. The virtual cessation 
      of range fires, over grazing, fencing, and other historic land use practices 
      have resulted in major vegetation changes.  | 
               
             
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