Time in the field: The joy of a soil pit

By the time this column reaches you, the cottonwoods along the Platte will be leafed out, the corn will be knee high across most of the Midwest, and those of us who have a field season will be back in the rhythm that drew us here in the first place. There is a reason the tone of this column is different from the last few. April was Capitol Hill. May was the Grassroots RFP. Both were necessary, and neither was the reason I became a soil scientist. June is well into field season, and for one month, I want to write about the part of this profession that does not appear on any appropriations line or strategic plan … the joy of a freshly dug pit.

What a pit gives you

I do not think we talk about this enough. A fresh soil pit has a smell. Anyone who has stood on the edge of one knows exactly what I mean. It is the grit you feel on your skin after you have been digging for an hour. It is the way the light changes as you scrape the face clean, and a boundary you could not see a minute ago suddenly resolves itself into a horizon. For a first-year graduate student at the edge of their first pit, the experience is mostly awe—they did not know soil could look like that. For someone further along, the experience is something different, and I think it has gotten richer over time rather than less.

A kid from the Ozarks, still

In my January column, I mentioned that I grew up in the Ozark Mountains of Arkansas and stumbled into soil science through an undergraduate microbial ecology lab. What I did not mention was the soil that hooked me.

It was a Captina silt loam, on the edge of the Boston Mountains, in the Ozark Highlands. I still remember the clay films. They were shiny, and the color on those subangular blocky peds ran from bright red to a darkened purple that I had never seen a mineral do before. Below that, the Btx horizon was unmistakable in a way you only understand once you have felt it—that brittle, seasonally perched resistance of a degrading fragipan. I was a kid from the mountains looking at his own landscape for the first time as a scientist, and it changed the way I walked home that evening. Argillic horizons and fragipans are still at the top of my favorites whenever I travel to a new region. Some soils just don't leave you.

That semester also pulled me into regional soil judging, which is where many of us in this Society first met a pit we did not dig ourselves. This spring's National Collegiate Soil Judging Competition, hosted in the Piedmont and Ridge-and-Valley country of North Carolina, is the newest entry in a long line of those formative weekends. Look at the photos if you have not. Look at the students' faces.

The riddles are already doing this work

Some of you may have noticed that the Soil Riddles section in this magazine has been, among other things, quietly lyrical. That is on purpose. The riddles are poetry with science in them, and they do what this column is trying to do—they remind you that a soil profile is worth describing beautifully because it is beautiful.

Consider a few lines from April's Riddle 1:

In Bt the clays begin to show, Silty clay loam where illuviation's slow.

But deeper still, a hardened floor, My 2Btx fragipan is brittle to the core.

If that soil sounds familiar to you, it should. It is the ground I grew up on.

The reason we do the rest

The Grassroots RFP is live. The workforce challenge is real. The funding fight is not going away this summer. And we do all of it—the Hill visits, the Board meetings, the grant submissions, the 5 a.m. emails—because of what the field gives us and what we want the next generation to feel the first time they stand at the edge of their own pit.

An invitation

This month, go to the field. If you have lost the habit, start small—walk a roadcut, pull a core, scrape a fresh face on an exposure you know. If you have students, bring one with you. Bring two. Let them get their hands dirty. Let them smell it. Let them feel the grit. Tell them what the horizons mean, and point out where the story is not finished yet because it never is.

Then dig a hole, and remember why.