As if the dandruffy flurries of snow and biting winds weren’t clue enough, a sure sign of winter is the presence of snow fences on the Iowa State campus.

The fences go up as late in the fall semester as possible, said Dennis Erickson, the manager of the grounds department of Campus Services. Grounds maintenance crews try to preserve the beauty of campus until the last possible moment.

“We try to wait as long as we can because they’re not as aesthetically pleasing as they could be,” he said. “We like to wait until after all of the home football games. We [had] one this weekend, but we’ve got to put them up before the ground freezes so we can get the posts in.”

Once the birds start chirping and the winds warm up, the crew that takes down the fences will do so with all deliberate speed. “We try to get them out as early as the grass starts growing,” Erickson said.

While a dragging Iowa winter might push that date back until late March or early April, as was the case last semester, Erickson said the fences come down by Veishea for sure.

The grounds department has been erecting these fences for “over 30 years,” Erickson said. Grounds workers put up about three miles of fence each winter.

The grounds crew keeps busy putting up fences in three areas: the main campus, the Vet Med College and Towers.

“Some of them are for snow, particularly out at Vet Med and Towers,” he said. “They keep snow from going out onto the roads.”

Snow fences do their job by creating an obstruction in the path of blowing snow. Flurries hit the fence and drift against it, instead of swirling onto roads or parking lots. Fences allow grounds crews to “control the drift.”

On the main campus, there are “some fences that play that role,” Erickson said, “but many keep pedestrians from crossing in the snow and making a path.”

Since grass isn’t growing during the winter, it is more susceptible to damage by walkers.

But snow fences are a last resort.

Erickson said the grounds crew tries its best to create alternatives to snow fences that act merely as road blocks on campus, either by putting up shrubbery to cut off the path or by building a sidewalk.

But sometimes these choices aren’t feasible, especially in places like central campus between Beardshear and Curtiss Halls, where many students tramp across the grass diagonally. Snow fences are just easier and more cost-effective at preserving the greenery.

While there’s no special design the crew uses when putting up the fences, Erickson did say the height of the fence and its “distance away from the area you’re trying to protect” are important in calculating the layout of the fences.