How do hairy flower stalks help cottongrass and willows grow in the tundra?

In the tundra ecosystem, the hairy flower stalks of cottongrass and willows serve as a vital adaptation for survival in harsh, cold environments. These hairs function by retaining warm air, which effectively raises the temperature in the immediate vicinity of the stalks by 3–9 °C (5–15 °F).1

This localized warming is crucial because it allows these plants to successfully flower and complete their reproductive cycles in areas where ambient air temperatures may hover near the freezing point. By maintaining a warmer microclimate around their reproductive structures, these plants can thrive despite the short growing seasons and cold conditions characteristic of the tundra.1