EPOW - Ecology Picture of the Week

An Arctic Field of Cotton

White Cottongrass (Eriophorum scheuchzeri arcticum), Family Cyperaceae
Spitzbergen, Svalbard, Norway

Explanation:  Adorning this arctic tundra landscape is a dappling of white cotton.  But this is not true cotton.  This is white cottongrass, a common, circumarctic genus of plants that produces a cotton-like white fluff.

So the first thing to clarify is that true cotton -- as used in many crops around the world -- belongs to the plant genus Gossypium in the botanical family of mallows, Malvaceae.  But white cottongrass belongs to the widespread genus Eriophorum of the family of sedges, Cyperaceae.  They are superficially similar but very different botanically.

Cottongrass -- including our arctic specimen here -- produces seed heads of fibrous white fluffs that catch the wind and help the attached seeds disperse, a mechanism known as amenochory or wind-dispersal.  

A number of other plants have developed wind-dispersal mechanisms, such as the helicopter-like seeds of maple trees.  Unlike the maples, cottongrass is also wind-pollinated.  

But I digress.

We are on the island of Spitzbergen, in the archipelago of Svalbard, of the country of Norway, in the very far northern arctic.  Two other species of cottongrass are found here.  Our white cottongrass differs in several ways, the most obvious in having a single (rather than multiple) stalk (spike) with a seed head.  

So welcome to the arctic land of cotton(grass)!