Precipitation during the coldest quarter 0.113373 Precipitation during the hottest quarter 0.126412 Ratio of precipitation to potential evapotranspiration 0.249609 Solar interception 0.457558 Nitrogen content of soil 0.501192 Compound topographic index (relative wetness) 0.549918 Bulk density of soil 0.553369 Carbon content of soil 0.640101 Sum of monthly Tavg where Tavg >=5 deg C 0.73985 Precipitation during the wettest quarter 0.774247 Temperature during the hottest quarter 0.83381 Day/night diurnal temperature difference 0.887007 Precipitation during the driest quarter 0.915673 Available water holding capacity of soil 1.26926 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 1.33016 Temperature during the coldest quarter 2.1735