On the Perils of Being a Farmer and a Math Nut
You know in “Your Majesties” from Rodgers and Hammerstein's Cinderella, where the chef, steward, king, and queen are singing about the preparations for the ball and “seventeen hundred guests”? Now, you may listen to it and see it (as I'm sure they intended) as a silly bit of nonsense, and think, “Wow! That's a big feast.” But my brain has a lamentable tendency to go, “Get real! No-one could possibly eat half a lobster's worth of salad, a third of a pheasant's worth of pie, over half a pound of caviar, a third of a suckling pig, and the lettuce from 1000 square feet of market garden!
So when the chef sings, “I told the steward to get us forty acres of lettuce, and six hundred suckling pigs for roasting,” I'm thinking... OK, you normally get feeder pigs at 8 weeks and 40 pounds, and they have been weaned for a little while. So a suckling pig is younger than that. Let's say, 6 weeks and 30 pounds or so. And a lot of that weight is guts and bones, so in actual meat...let's be generous and say one might feed 20 people. So that would feed twelve thousand people. That's about seven times more than they need, even if you don't account for all the other food they're serving...
And forty acres of lettuce is just way out there. An acre covers a 208-foot square. When we grow baby lettuce mix, we break our plots up into 8-foot wide strips, each of which has two thirty-inch wide beds in it. So fifty-two 208-foot long beds would make an acre. That's 10,816 feet of bed space. A good yield for one cutting (with baby lettuce you cut it just above the growing tip and let it regrow, so you can harvest one planting two or three times) is one pound of salad mix per foot of bed. So we get about 10,800 pounds per acre.
The usual catering estimate is that a pound of lettuce serves 20 people. So we're looking at about 216,000 people per acre of lettuce, and forty acres of lettuce would feed about 8.6 million people.
--Josh Grams <firstname.lastname@example.org>