Precipitation during the hottest quarter 0.399155 Nitrogen content of soil 0.579105 Precipitation during the coldest quarter 0.753771 Available water holding capacity of soil 0.842114 Precipitation during the driest quarter 1.00206 Compound topographic index (relative wetness) 1.00997 Precipitation during the wettest quarter 1.04193 Sum of monthly Tavg where Tavg >=5 deg C 1.24718 Solar interception 1.37274 Ratio of precipitation to potential evapotranspiration 1.46474 Temperature during the hottest quarter 1.54831 Temperature during the coldest quarter 1.94171 Elevation 2.52206 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 2.74378 Carbon content of soil 3.50697 Bulk density of soil 4.17223 Day/night diurnal temperature difference 6.6119