Amadeus Schmidt wrote:
The grassland (at least in temperate regions as here in middle

> europe) isn't a natural habitat. It is created by the free-range
> meat and milk procuction
> - otherwise the areas below the tree-boundary would
> rather fast turn into wood.

Where I live (Colorado), grass is the natural state.  Trees
(other than along streambeds) are the anomaly.  Almost half of
the U.S. land is suited for grazing, not for agriculture, and can only
grow trees when they are watered by human intervention. Well-regulated
grazing is more ecologically sound in this region than plowing it up,
planting corn, and watering it from the fast-diminishing aquifers.

Lynnet