4.                            C A S C A D E S                                                                                                                                                                                                                                                                                                                                                                             

      Level IV Ecoregion                                   Physiography                                                              Geology                                                                          Soil                                                                        Climate                                            Potential Natural                         Land Use and Land Cover    
                                Area                                                           Elevation /                  Surficial material and bedrock                Order (Great Groups)                             Common Soil Series                Temperature  /     Precipitation     Frost Free      Mean Temperature                       Vegetation                                                       
                               (square                                                        Local Relief                                                                                                                                                  Moisture Regimes    Mean annual       Mean annual      January min/max;
                               miles)                                                             (feet)                                                                                                                                                                          (inches)            (days)      July min/max, ( F)                                                                                      

4g. Southern                   1049 Mountains with moderate slopes, broad                     2600-5800 Pliocene basalt and basaltic andesite.                      Alfisols (Haploxeralfs), Inceptisols  Freezener, Geppert, Straight, Farva,                  Mesic,             45-60           90-120              26/45;           White fir, Douglas-fir, ponderosa pine;  Extensive rather open conifer forests with white
                                           valleys, and medium to high gradient streams             /                                                               (Xerochrepts, Xerumbrepts),              Pinehurst, Dumont, Coyata.                         Frigid/                                                47/85            some Shasta red fir, mountain                  fir often common. Douglas-fir and ponderosa pine
      Cascades                                                                                                                                                                                                                                                                                                                                                                                                            
                                           and rivers. Reservoirs, a few large mountain       400-2400                                                              Ultisols (Palexerults), Mollisols        Moderately deep to deep, loam,                      Xeric                                                                  hemlock.                                       are prevalent at low elevations and Shasta red fir
                                           plateau lakes of glacial origin, and a high                                                                              (Argixerolls)                            gravelly loam, very cobbly loam.                                                                                                                                          grows at high elevations. Land uses include
                                           number of intermittent streams.                                                                                                                                                                                                                                                                                                             forestry, recreation, and some grazing. Ecoregion
                                                                                                                                                                                                                                                                                                                                                                                       4g is an important regional water source.