In September the Earth rounds an elongated curve in space and the weather begins its languorous glide into the long slog of winter. September suffers from multiple personality disorder, with summery heat one day and an autumn chill the next. The furnace will be running in the morning and we’ll need the air conditioner by afternoon.

September finds farmers busily laying in supplies for the Long Cold, like squirrels who have been given access to a vast array of industrial scale harvesting equipment.

At this time of year in our neck of the woods, it’s not uncommon to catch a particular tang in the air. It’s an aroma that simultaneously reminds me of rising bread and brewing beer and fresh pickles. It’s the magical perfume of fermenting corn silage.

Nobody knows who first conceived of the idea of chopping up corn plants and allowing the hot, wet mess to ferment. Perhaps it was the brainchild of some guy who had a new paper cutter and too much time on his hands. Or maybe it was inadvertently invented by a traveling salesman who was eager to demonstrate his large assortment of Ginsu knives.

Powered silage choppers arrived on the scene about a century ago. The newfangled contraptions, which were stationary, would throw the silage a good distance as the chopped fodder exited. It quickly dawned on farmers that erecting a tall tube next to this gizmo would enable them to store considerable quantities of feed for the winter. This gave rise to the upright silo.

Things had improved by the time I came along, although not by much. When I was a youngster, Dad owned an ancient single-row silage chopper. It was basically an old-fashioned stationary chopper mounted on a set of wheels.

When September arrived and the golden kernels of our corn began to dent, Dad would couple his Farmall “M” to the rickety chopper and hitch a silage wagon behind it. He would then pilot this Goldberg-like conglomeration of moving parts down a row of corn.

My siblings and I were encouraged to ride in the wagon. Our mission, should we decide to accept it, was to walk on the silage as it spewed from the chopper’s curved spout. The theory was that we would pack the silage and thus increase the wagon’s holding capacity. In practice, this was about as effective as using your feet to pack water. But I suppose it kept us out of trouble.

It was exhausting to wade through the fresh silage as we dodged the torrent of slimy green plant material. The decrepit chopper wasn’t very efficient at turning corn plants into uniformly small pieces. Getting bonked with a chunk of corn cob the size of a hubcap was a common hazard.

The “M” had barely enough oomph to power everything. If anything was the least bit amiss — if the moon was in the wrong phase or the corn was especially tall, or the wagon was becoming especially full — the tractor’s engine would lug and chug as its RPMs dropped into starter motor territory. The mighty stream of freshly chopped silage would droop to a feeble dribble.

But we always somehow managed to fill the wagon. Dad would unhitch it from the chopper and hook it onto another tractor and pull it onto our farmyard. Early in the silage season, when the corn was too wet to store in the silo, he would simply make a small pile of silage near our dairy barn. My siblings and I would play King of the Hill on the forage pyramid. Slices of corn cob were chucked at one another like ninja throwing stars. We hurled cob discs at the sky, miniature Frisbees soaring into the deepening twilight.

This was just a warm-up for the main event. Sometime in September a crew of neighborhood farmers would appear at our farm, bringing with them a fleet of wagons and a huge — it took two rows! — silage chopper. An enormous blower was parked beside our silo and connected to a set of 9-inch galvanized pipes.

A pair of the men would toil like maniacs as they raked wagonload after wagonload of silage into the insatiable blower. The air soon became filled with the heady fragrance of fermentation.

Nowadays, silage choppers the size of battleships cruise through our September corn fields. Choppers that have more power than the Hoover Dam, filling gigantic trucks that will never feel the jab of a silage rake. Choppers that efficiently process the corn plants into small, uniform pieces. There are no corn cob Frisbees to throw.

But there is one thing that technology hasn’t changed: the wondrous aroma of fermenting corn silage.