If you were a rancher and you were under serious threat at some unknown point in the future, the best, most cost effective action would be to leave. That whole position is a deathtrap, most homes in general are.
Assuming Earls got equal numbers to the tranchers, then any half decent attack could hit from 2-3 directions. There's no good cover in the area at all, maybe the building basement if its got a sunken foundation. The rest is concealment at best and won't stop much, shitpiles excluded maybe. If they're getting hit from multiple directions, that concealment is pretty much moot, as its scattered, isolated structures. I doubt any one position they could take would be concealed from multiple likely angles while also being useful to return fire, so their only real option is hit the dirt or stay in the house. If they stay inside, that building is gonna be on fire in short order, concentrated gunfire will start hitting electric lines, gas, storage batteries, etc. If they stayed in the house or basement, now they're fucked.
If they had more than 2-3 of them outside, and they weren't shitting themselves in fear at this point, they could try fire and maneuver drills, if they figured out where the shots were coming from. Disregarding that they'd still be taking fire from multiple directions for a moment, they're still fucked. It takes an incredible amount of training and confidence to do bounding actions into oncoming fire. You need to absolutely fucking trust the guys behind you to keep heads down, and you need to trust that the spot your going is at least as safe as where you were. Troons are delusional, so I can see them trusting each other to that level, but even experienced soldiers should be sweating bullets at the idea of trying to bound along open, desolate shrubland, with no real dips or peaks to take advantage of. The place is really fucking flat, and that'd be the end of them. Seriously, entire generations of infantry fighting vehicles have been dedicated to the problem of keep infantry alive over large, desolate tracts of land.
The militia don't need to be brave, iron soldiers to make this happen either. The attackers advantage is gonna be getting to a position you feel good with, and then firing from it until they're dead. Normally that's the defenders advantage, but we all know they're not actually running proper defenses, one twitchy troon in a window is not good area defense. Done right, they don't need to run around much. A handful of spiteful ranchers could easily be coordinated enough to set up that crossfire.
In a realistic scenario, the militia set up the crossfire, open up as night sets in and the troons are going to bed, catch a couple out in the camper slums. The rest either give up on the spot, or the house troons go full retard, gear up, and start looking out windows or running out doors, and get lit up too. Militia fades into the night, and the ranch survivors scatter to the wind for their seven figure book deals. Everyone wins.