So I'm thinking of running an E6 campaign with no full-progression casters (or, alternately, having them use Spheres of Power). It's supposed to be somewhat gritty, and being in a frontier area I'm going to be playing up interaction with the local environment. However, I'm having quite the hard time figuring out how to adjudicate how much time and what sort of rolls (if any) are necessary for some of these things:
1) Digging a pit - a 10-foot deep pit that's 5-feet wide and long (your basic pit trap, in other words) probably shouldn't require any rolls, but I'm not sure how long it takes to dig (without getting into all sorts of cumbersome equations...let alone issues of Strength scores, how many people can participate, adamantine shovels, etc.). This also goes for trenches.
2) Making a berm - roughly the same problem here, insofar as time adjudication goes. This is made with the displaced earth from digging a pit. I'm mostly confident no rolls are needed here either.
3) Chopping down trees - This one seems a lot simpler. Wood has hardness 5, and 10 hp per inch of thickness. The issue is that there's a question as to whether or not that's too much for "just" chopping a tree down, since usually that's enough to open up a 5-foot square in a wall.
4) Damming a river - I have no idea how to adjudicate this. Presumably there's some sort of skill check involved, and the dam would have hardness and hit points?
5) Salting the earth - Alkalizing a patch of earth so it won't ever grow anything again (at least for a while). For a 5-foot by 5-foot patch of earth, how much salt does this take, how much would that salt cost, and how long would it take to do this? Would any rolls be involved?
6) Erasing a scent - Obviously a stronger scent can cover up a weaker one. But besides a powerful chemical, or a skunk, what can do this? Is there a scent equivalent to covering yourself in mud to hide your body heat? There's presumably some intersection of Perception and the scent ability here, but the specifics seem vague.
7) Insects as irritants, not threats - Presuming that things like mosquitoes don't become deadly swarms, what's a good way to treat them as irritants that have some sort of mechanical effect don't rise to immediately life-threatening dangers?
8) Sleeping in trees - This isn't really an issue of altering the environment, but I'm not sure if I should hand-wave this or not. Would this require a Reflex save not to fall out of the tree during the night? Can you get sufficient rest while tucked in branches?
10) Smoke signals - I'm tempted to have this just be a language, taken with a single rank in Linguistics. Presumably there wouldn't need to be much of a Perception check within a few miles, at least during the daytime.