Available water holding capacity of soil 0.21755 Sum of monthly Tavg where Tavg >=5 deg C 0.338036 Precipitation during the coldest quarter 0.398457 Precipitation during the wettest quarter 0.412817 Nitrogen content of soil 0.43234 Precipitation during the hottest quarter 0.434238 Ratio of precipitation to potential evapotranspiration 0.480245 Solar interception 0.746852 Precipitation during the driest quarter 0.790768 Compound topographic index (relative wetness) 1.01938 Carbon content of soil 1.45323 Temperature during the hottest quarter 1.48845 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 1.54333 Elevation 2.03337 Temperature during the coldest quarter 2.16218 Bulk density of soil 2.67843 Day/night diurnal temperature difference 3.94184