From the Sarna article for the Unlimited version of the card: “The first rule of jungle warfare is, obviously, eliminate the jungle.” — Star Captain Glen Osis, Clan Smoke Jaguar, Albiero, July 3050
Interestingly Sarna's article on the world indicates there likely isn't much in the way of jungle and that it's more likely the local defenders would have hold up in the planets extensive tunnel network (In single biome planet terms the planet is dug out mine town)