Precipitation during the wettest quarter 0.000121 Nitrogen content of soil 0.501749 Precipitation during the coldest quarter 0.60318 Precipitation during the driest quarter 0.670888 Ratio of precipitation to potential evapotranspiration 0.673592 Precipitation during the hottest quarter 0.742361 Carbon content of soil 0.775854 Bulk density of soil 0.883717 Compound topographic index (relative wetness) 1.04692 Temperature during the hottest quarter 1.59029 Solar interception 2.05567 Available water holding capacity of soil 2.1925 Day/night diurnal temperature difference 2.24573 Sum of monthly Tavg where Tavg >=5 deg C 2.57326 Temperature during the coldest quarter 2.68327 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 3.04624