Day/night diurnal temperature difference 0.229153 Temperature during the hottest quarter 0.478123 Nitrogen content of soil 0.585767 Compound topographic index (relative wetness) 0.650891 Carbon content of soil 0.72069 Precipitation during the wettest quarter 0.767646 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 0.847625 Precipitation during the driest quarter 0.904471 Elevation 0.927482 Sum of monthly Tavg where Tavg >=5 deg C 1.20545 Bulk density of soil 1.33574 Available water holding capacity of soil 1.82972 Solar interception 2.78922 Temperature during the coldest quarter 3.1978 Precipitation during the coldest quarter 3.68218 Precipitation during the hottest quarter 3.99059 Ratio of precipitation to potential evapotranspiration 4.33628