Step 1: Allee's 1949 biome scheme divides the terrestrial world by climate and dominant vegetation into named units: tundra in the cold arctic zone, taiga as the coniferous forest belt just south of it, and grassland as the biome of temperate open plains.
Step 2: Each of these three has a specific climatic and vegetational definition attached to it in the classification.
Woodland does not appear as a separate formal biome category in this scheme, since wooded areas are already covered under the forest biome types.
