The Underground Campus

Field Notices

Luther College Chips
November 20, 2008

The underground campus—that safe haven where mind-blowing chemical transactions are going down all the time—is a place few ever see.

That’s too bad because we spend much of our day beating its upper surface with the bottoms of our shoes.

Yes, I’m talking here about the literal underground campus, the part of Luther College where living things are surrounded by more dirt and stone than air.

The perfectly obvious reason we rarely see that environment is that we need air to live. We only put people in the ground when what’s left of them won’t be needing oxygen any more.

But put on that funky imagination hat of yours for a few minutes and travel with me down the proverbial rabbit hole for a quick adventure in underland. For the sake of easing our transport, let’s imagine that like Alice, for our journey we get very, very tiny.

As we shrink down to the size where we disappear into the turf grass on the bell green to venture downward, we immediately feel topsy turvy. Under all that grass is its pale, thin, slightly longer and more twisted double, growing in reverse. A grass plant is a bit like Johnny Depp Siamese-twinned to Brad Pitt by the soles of his feet. We are used to seeing the green, wide-bodied Brad Pitt side of grass that stretches always toward the sun. But before that side can start growing, its flip Johnny Depp side must ease twisty roots away from the light, down into the soil.

If big picture vision were allowed us on this journey, we would now see the upside-down canopy of tree roots all across campus spreading out around us, and stretching to astonishing depths below the tips of the grass roots.

The nature of turf grass as well as for trees is to roughly equal the living mass above and below ground, so for every massive oak, maple, cottonwood and pine you used to see stretching above you on your jog-trot between classes there is now a root mass of equal size stretching below into the darkness.

Had we made our underground sightseeing trip under Anderson Prairie, an even bigger surprise would wait for us. Instead of inches of roots anchoring inches of grass, as on the lawn, the four to six feet of prairie grass is anchored by 12 to 18 feet of roots. Prairie puts two to three times as much energy below ground as above.

But big picture vision and cross-campus leaps are emphatically not allowed. In fact, what with all this dirt, it’s getting dark, and more and more crowded as we go. Within seconds we can see little. To go forward we might as well forget about those feet of ours. Transport has now become a scratch, wriggle, and squirm operation where head first is clearly superior to feet first.

The tight squeeze can’t be blamed only on geology. It’s crowded underground. The 13-lined ground squirrels that poke their heads out of holes near the library and which you used to consider cute in your large aboveground life are massive, top-of-the-food-chain monsters down here. Besides grass and roots, they gobble earthworms, wireworms, caterpillars, beetles, ants and insect eggs. That list describes the bigger company you are now jostling as we make our way.

But pull your magnifying glass out of your very, very tiny pocket and, if we can find a light, you’ll see that as you go smaller the population climbs: microbes in their thousands and bacteria in their billions press around you.

In every square foot of highly active, organic soil, there can be five pounds of animal life, most of it incredibly small.

Roots and fungal hyphae weave the soil together like a net. At this tiny level, creatures swarm in what’s called the “rhizosphere,” a frantically busy little environment emanating out from each root.

It’s at this tiny not-easily-seen level that all the complicated chemical dealing goes on underground. Roots release acid, sugar and water, trading them to microorganisms for the vitamins, hormones, antibiotics and minerals they give in return.

If we have been lucky enough to find a little patch of campus lawn that the broadleaf herbicide has missed, we might come across the roots of clover. Clover and other legumes develop root lumps that house bacteria which transform inert atmospheric nitrogen into the fertilizing nitrogen compounds plants need. More microscopic dealing: the plant swaps home, the bacteria swaps food.

As the snow starts to fall, the temperature sinks below freezing and the leafy, buzzing world aboveground grows bare and quiet, soil around us remains active. In this sheltered space plants have stored nutrients for next spring, insects have deposited eggs or larva for a future hatch, and amphibians and mammals (like those ground squirrels) have burrowed in for a quiet season of sleep. It’s one happening scene.

But don’t panic. We can come out now, dust off, and expand back to our normal—wait, from our new underground perspective make that Jurassic—size.

And don’t feel sorry that you’ve missed the underground campus up until today. It’s probably not your kind of place. But don’t dismiss its importance. As you can tell, its dark economy of exchanges is where aboveground life begins.