Sum of monthly Tavg where Tavg >=5 deg C 0.509913 Bulk density of soil 0.510115 Nitrogen content of soil 0.606589 Compound topographic index (relative wetness) 0.629699 Precipitation during the hottest quarter 0.636543 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 0.718372 Precipitation during the coldest quarter 0.728249 Precipitation during the wettest quarter 0.79084 Ratio of precipitation to potential evapotranspiration 0.838504 Precipitation during the driest quarter 0.988621 Carbon content of soil 1.13646 Solar interception 1.17522 Available water holding capacity of soil 1.26423 Elevation 1.26896 Temperature during the coldest quarter 1.282 Temperature during the hottest quarter 1.77024 Day/night diurnal temperature difference 2.82819