Precipitation during the wettest quarter 0.000603 Precipitation during the driest quarter 0.393356 Compound topographic index (relative wetness) 0.397153 Nitrogen content of soil 0.444925 Carbon content of soil 0.65892 Ratio of precipitation to potential evapotranspiration 0.665321 Temperature during the hottest quarter 0.716461 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 0.730941 Precipitation during the hottest quarter 0.731356 Day/night diurnal temperature difference 0.767505 Elevation 0.80593 Precipitation during the coldest quarter 0.909032 Bulk density of soil 0.912722 Available water holding capacity of soil 1.12503 Solar interception 1.15646 Sum of monthly Tavg where Tavg >=5 deg C 1.39401 Temperature during the coldest quarter 2.07764