Raunkiær plant life-form

The Raunkiær system is a system for categorizing plants using life-form categories, devised by Christen C. Raunkiær and later extended by various authors.

History

It was first proposed in a talk to the Danish Botanical Society in 1904 and briefly described in the society's journal Botanisk Tidsskrift.

A fuller account appeared in French the following year. Raunkiær elaborated further on the system and published this in Danish in 1907.

The original note and the 1907 paper were much later translated to English and published with Raunkiær's collected works.

Modernization

Raunkiær's life-form scheme has subsequently been revised and modified by various authors, but the main structure has survived.

Subdivisions

The subdivisions of the Raunkiær system are based on the place of the plant's growth-point (bud) during seasons with adverse conditions (cold seasons and dry seasons):

Phanerophytes

Projecting stems into the air – normally woody perennials - with resting buds more than 25 cms above soil level, e.g. trees and shrubs, but also epiphytes, which Raunkiær separated out as a special group in later versions of the system.