Precipitation during the wettest quarter 0 Day/night diurnal temperature difference 0.021788 Compound topographic index (relative wetness) 0.141126 Temperature during the hottest quarter 0.148853 Nitrogen content of soil 0.207426 Carbon content of soil 0.221217 Precipitation during the driest quarter 0.274307 Elevation 0.32228 Bulk density of soil 0.36998 Sum of monthly Tavg where Tavg >=5 deg C 0.46989 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 0.615575 Precipitation during the hottest quarter 0.933557 Precipitation during the coldest quarter 1.09109 Available water holding capacity of soil 1.19955 Solar interception 1.28804 Ratio of precipitation to potential evapotranspiration 1.40759 Temperature during the coldest quarter 1.45989