Available water holding capacity of soil 0.355131 Precipitation during the hottest quarter 0.438788 Sum of monthly Tavg where Tavg >=5 deg C 0.58717 Precipitation during the coldest quarter 0.63469 Nitrogen content of soil 0.647052 Compound topographic index (relative wetness) 1.01264 Ratio of precipitation to potential evapotranspiration 1.08529 Precipitation during the driest quarter 1.2103 Precipitation during the wettest quarter 1.23468 Solar interception 1.23616 Temperature during the hottest quarter 1.89741 Integer number of consecutive months where Tavg >= 5 deg C (Length of potential growing season) 1.98519 Carbon content of soil 2.35971 Temperature during the coldest quarter 2.40391 Elevation 2.82657 Bulk density of soil 3.49181 Day/night diurnal temperature difference 4.32458