Rust Horse Farm Economics

How horse dung works

A horse eats food from a Hitch & Trough, and every calorie it digests becomes dung. The game converts 0.1 dung per calorie, but a horse only digests up to 100 calories per hour — so a single horse produces at most 10 dung per hour. Extra food isn’t wasted: uneaten calories are banked and digested later, so keeping the trough stocked keeps the horse at max output.

Each piece of Horse Dung then composts into 5 fertilizer — the best ratio of any compostable item. That chain (10 calories → 1 dung → 5 fertilizer) is what makes horses so strong: at the 100 cal/hr cap, one horse yields up to 50 fertilizer per hour.

The economics: feed → dung → fertilizer

Because every calorie is worth half a fertilizer, high-calorie crops are the best feed. Here is what common farm crops convert into (rate-capped at 100 cal/hr per horse):

Why not just compost the crops?

Composting a crop directly yields only 0.2–0.3 fertilizer per item. Feeding that same crop to a horse first turns its calories into dung, and dung composts at 5 fertilizer each — so routing food through a horse produces vastly more fertilizer than composting it raw. One corn composted directly is ~0.3 fertilizer; fed to a horse it becomes ~38.

This creates a self-reinforcing loop: grow fertilized crops → feed the surplus to horses → compost the dung into fertilizer → grow even more. A couple of horses can fertilize a large farm indefinitely.

Setting up a horse farm

1. Place a Hitch & Trough and hitch a horse to it (horses are found in the world or bought at the Ranch / stables).
2. Fill the trough with high-calorie food — potatoes, pumpkins, or corn from your farm.
3. Let the horse eat and produce dung; collect the dung that drops beneath it.
4. Feed the dung into a Composter to turn it into fertilizer (5 each).
5. Use the fertilizer on your planters, and feed the extra harvest back to the horses.