Nitrogen content of soil 0.432243 Carbon content of soil 0.708613 Precipitation during the wettest quarter 0.753423 Sum of monthly Tavg where Tavg >=5 deg C 0.86167 Precipitation during the driest quarter 0.907001 Ratio of precipitation to potential evapotranspiration 0.908129 Precipitation during the coldest quarter 0.983491 Compound topographic index (relative wetness) 1.26939 Precipitation during the hottest quarter 1.37585 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 1.40849 Bulk density of soil 1.47579 Available water holding capacity of soil 2.22373 Temperature during the coldest quarter 2.43268 Day/night diurnal temperature difference 2.60191 Temperature during the hottest quarter 2.65399 Solar interception 2.90042