Three-field system

Instead of resting half the land each year, medieval villages split it in three: an autumn crop, a spring crop and one field fallow. That alone brought an extra sixth of the arable into use every year. The spring field grew peas, beans and lentils for people, plus oats and barley for horses. Those oats are the quiet hinge of the early entries here, since they fed the collared horses that worked faster than oxen. Historians still argue over whether yields per acre rose much, so the safest claim is more land cropped and a village's labor spread across two sowing seasons instead of one.