The horse collar got to England by the 12th Century — around or just after the late Norman era. However, it took until the early 19th Century (c. 1840) for oxen

The horse collar got to England by the 12th Century — around or just after the late Norman era. However, it took until the early 19th Century (c. 1840) for oxen to finally disappear from the plowfield. Why? Expense. In Domesday era [c. 1066-1086, before the horse collar advent] small tenant farmers could get away with a single yoke of oxen — a single pair. While large farms used teams of up to 8 to pull a plow through the rough clay. As the medieval period transitioned into the modern you saw larger and larger farms. A Domesday era villein might keep only 120 acres under plow (48 hectares); a small holder with a single yoke might only hold 30-40 acres (12-16 hectares). Average farm sizes continues to grow to this day. Today the average English farm is nearly 220 acres (88 hectares). Larger farms, and more varied farmwork, meant the expense of horses could be afforded better. A chart in this report shows how the sheer number of horses did not equal the number of oxen until the late 15th Century, when it was estimated a little less than 400,000 of each creature plowed fields throughout Britain. There was a gap in the records until the middle of the 16th Century. By then, and afterwards, the number of horses well exceeds the number of oxen. That number continued to skyrocket into the Victorian era, by which time use of oxen was nearly eliminated. And then, when the steam engine (and eventually petrol engine) tractors came along, you'll see the agricultural horse population likewise collapse. https://ir.library.louisville.edu/cgi/viewcontent.cgi?article=1882&context=faculty https://ir.library.louisville.edu/cgi/viewcontent.cgi?articl...