A Side Note About Acres

I've learned a lot of specific Saint Paul facts from my favorite Christmas present, Donald Empson's book The Street Where You Live: A Guide to the Place Names of St. Paul. In fact, I've spent the past couple of days jumping in and out of rabbit holes related to the history of my neighborhood, partly because of what I found in the book and partly because the Star Tribune has had its archives open on newspapers.com during the holiday weekend.

But here's one general fact I learned from Empson that I don't remember learning before:

The amount of land that could be worked by one person in one day was four square perches, or one daywork. An acre, the amount of land a team of oxen could plow in one day, equaled forty dayworks (page 5).

Checking elsewhere online, I see that a perch is considered to be 16.5 feet in length. For visualization purposes, this helpful site says a square perch is about the size of half a tennis court.

I remember learning about rods and stones in school, but I don't remember ever hearing of perches or dayworks (though it sounds like perch may be interchangeable with rod? or maybe perch is always the square of a rod). And in what I did learn about acres, I don't recall this reference to how much land a team of oxen could plow in a day.

I still don't understand what a hectare is. No, I'm not going to look it up. 

(Happy New Year!)