Grassland or Plains

[Flash]

Hello All,

As I sit here, I'm working on the land and vegetation of Australia. As I look at my atlas, I face a delima... How do I deside what land should be defined as grassland and which should be defined as plain?

The choices that I need to define (Note, some are obvious):

Alpine

Desert and Desert Scrub

Mid-Latude Forest:
... Broadleaf Forest
... Coniferous Forest
... Mixed Coniferous and broadleaf Forest
... Mixed Woodland
... Woodland and Scrub (mediterranean)

Mid-Latitude grassland:
... Short Grass (Steppe)
... Tall Grass (Prairie)
... Tall Grass (Prairie) and Wooded Steppe

River Valley And Oasis

Scrub and fernland

Tropical Forest
... Tropical Rainforest
... Light Tropical forest
... Woodland and Scrub

Tropical Grassland
... Savanna
... Wooded Savanna

Tundra and Alpine

Permanent Ice