Fungus/Xenofungus  
Xenofungus or Fungus is a form of plant life native to Alpha Centauri. It has a number of unusual properties which you may discover in the course of play. Some of the more obvious properties include:

(1) Fungus impedes movement. Units may have difficulty entering Fungus squares. Increasing your PLANET social engineering rating will alleviate this problem. Building the Xenoempathy Dome improves Fungus movement considerably.

(2) Fungus has some defensive value when defending against other human factions. Against alien Mind Worms, however, Fungus has negative value.

(3) Fungus squares can be tapped for resources; the resource level provided by a fungus square is determined by the number of Centauri technologies you have discovered.