The Walking Forest

On Staurn, the Walking Forest attacks Heim's party and they must fight their way through.

Preliminary theories of the forest:

the abundant ultraviolet from Staurn's sun makes plant chemistry unusually energetic;

those trees need a particular mineral so a wood appears whenever faulting exposes a vein;

geology is faster on bigger planets so maybe this form of life can depend on geological accidents;

or maybe bacteria deposit organic material that is exposed fairly often;

the trees could broadcast spores that lie dormant for centuries;

the spores sprout and consume the deposits;

the forest must keep moving because it exhausts the soil where it stands;

sunlight gets the trees moving;

when they exhaust a vein, they die and their reprocessed material wakens the spores that they have left.