Appendix A. A graph showing the relationship between heat sum and number of frost days along altitudinal gradients in the study regions.
FIG. A1. Relationship between altitude and (a) heat sum (degree days > 5°C) and (b) number of frost days (minimum temperature < 0°C) in the Valais (VS; filled circles) and the Wallowa Mountains (WM; open circles) from April to September 2005. The data were collected along four altitudinal transects (roads): Visp to Furka pass (VS; solid line), Martigny to Grand St. Bernard pass (VS; dot-dashed line), Mount Harris Loop (WM; dotted line), Moss Springs Rd (WM; dashed line). |