Precipitation during the hottest quarter 0.174979 Nitrogen content of soil 0.224257 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 0.269893 Precipitation during the coldest quarter 0.329526 Compound topographic index (relative wetness) 0.382202 Precipitation during the driest quarter 0.3873 Available water holding capacity of soil 0.421009 Ratio of precipitation to potential evapotranspiration 0.475799 Precipitation during the wettest quarter 0.514527 Bulk density of soil 0.630363 Elevation 0.653162 Carbon content of soil 0.66544 Sum of monthly Tavg where Tavg >=5 deg C 0.7326 Temperature during the hottest quarter 0.865172 Solar interception 0.98012 Temperature during the coldest quarter 1.45722 Day/night diurnal temperature difference 2.79214