SupplementaryMaterial 2 Descriptions and functional indications of the species morphological functional traits measured across the seven snowpatches. Traits were measured in the field and laboratory based on protocols outlined by Cornelissen et al. (2003).

Trait (unit) / Description / Functional indicator
Plant height (mm) / Shortest distance between the upper boundary of the main photosynthetic material (usually the canopy) and ground level / A measure of species overall competitive ability at plant maturity. Species that are relatively taller will be more competitive, usually for light. Indirect measurement for biomass, lateral spread, rooting depth and leaf size.
Leaf area (mm2) / One-sided projected surface area of an average leaf / A measure of stress tolerance. Small leaves tend to be favored under heat stress, cold stress, drought stress, and high-radiation stress. Within a climate zone, leaf size tends to increase with plant height and soil nutrients, but decreases with disturbance. Larger leaves are expected in more productive landscapes.
Percent dry weight of a leaf / The oven-dry mass of a leaf divided by the water-saturated fresh weight of the leaf * 100 / Indirectly represents the mean density of leaf tissue, relates to the inverse of SLA. Low percent dry weight can indicate fast resource acquisition. Leaves tend to be more resistant to physical stress such as wind and hail. Species with low percent dry weight tend to be associated with highly disturbed environments and high productivity.
Specific leaf area (SLA)
(mm2 mg-1) / Ratio of one sided area of a water saturated leaf to its oven dry mass / Low values correspond to relatively high investment in defenses to harsh conditions including long life spans and structural adaptations. Reflects the expected return on previously captured resources such as light and nutrients. A good positive correlate of potential growth rate.