“Soil is not dirt”

Dr. Griffin has taught soil science at Prairie View A&M, just outside Houston, for 35 years. He studies everything from wetlands and marshes to farm fields, and works on precision agriculture to help farmers grow better crops.

He called in from his phone, and the signal cut out right in the middle of his first answer, so he started the whole story over without complaining.

I didn’t know much about soil going in. I came out knowing why some lawns turn yellow in circles, why our streets flood, and that you can measure the water in your own yard with a nail. Here’s most of what he said.

Lightly edited so it reads easier. The words are his.

It started with FFA

You studied soil science at NC State and got your PhD at Texas A&M. Back in high school, did you know you wanted to study soil? Who made the biggest difference in getting you here?

“I first got interested in soils in high school. I was in the Future Farmers of America, FFA, and we did contests called land judging. Our team placed top five in North Carolina, which got us to the international contest in Oklahoma City, where teams come from around the world. It was my first time ever leaving North Carolina.”

“There I met a professor from NC State who told us about soil science as a major, and about jobs with the U.S. Department of Agriculture. Back then it was the Soil Conservation Service. Now it’s the Natural Resources Conservation Service. They also had scholarships, so that sounded good to me. I enrolled at NC State in soil science and stayed for my master’s. Then a professor from Texas A&M came and gave a seminar about PhD research. I wanted to study wet clays, and that’s what brought me to Texas.”

“I also had a really good FFA advisor in high school. He taught us so much about plants, the environment and natural resources. That really helped build my career.”

Do teens need to be 100% sure before they explore a field? Should they go for what they’re talented at, or what they love?

“I’ve found that if you figure out what you’re passionate about, you’ll spend that extra time doing the work it takes to really dig into it. And some days it doesn’t even seem like work. There are days I think, ‘Wow, I wish I could pay somebody to do this.’ At that point it’s not work. The fun is part of the exploration.”

Why some lawns turn yellow in circles

Houston has a lot of floods, bayous and empty lots. What’s a real project a teen could do in their neighborhood, without a lab, that makes an impact?

“A neat project I worked on some years ago was in Cinco Ranch, on the west side of Houston along I-10, with a Texas A&M professor who was interested in urban forestry. Parts of Cinco Ranch were built on old rice fields. You’ll notice all the homes are raised up, and the streets are the water collectors. Water runs off the lots and drops into the street. If a cul-de-sac isn’t perfectly on grade, water sits there during a flood.”

“Early on, spots in people’s lawns were turning yellow in circles, and certain trees were dying. In the old rice fields, some areas were lower than others, and those low spots held water longer. When the homes were built, they just leveled the ground over them. But the soil still has a memory of where those low spots were. They still hold water longer. Those are the wet areas in the lawn.”

The nail test

“So we took 12-inch nails, they’re called bright spikes, and cleaned off the oil that keeps them from rusting. We tied a little string to each one, and for the low spots we added a cork stopper so it would float. After watering, or in the wet winter season, the homeowner could pull the nail out of the ground and hold it up to a wooden stake with inch markings.”

“The rusted part of the nail is where water was sitting around it. So they knew exactly how much water was in their lawn. It just tells you, yes, there’s too much water here for too long.”

So you have to notice things people walking by would miss.

“That’s the scientific method. Observation. You see something you have a question about, and then you figure out some way to test what’s going on.”

Why the streets flood

“We’re surrounded by bayous in Houston, and I’m really interested in how water moves. The streets are actually the drainageways. At some point that water has to come off the street and drop into something lower, hopefully a bayou or a drain, and then keep moving downhill. If it can’t move downhill fast enough, it backs up, and that’s a flood.”

“One sign that soil has been wet for a long time is that it turns gray. Rusted iron is red or yellow. But if iron sits in water long enough, the whole soil turns gray. So next time you see a hole dug in the ground, look at the color.”

A yes, a no, or a maybe

A lot of teens feel like they don’t know enough to reach out to experts. How willing are professionals to talk with a student who has no experience but really wants to learn? What would you tell the ones who are too intimidated?

“It’s like what I see in the classroom. If someone has a question and they’re too timid to ask it, somebody else almost always has the same question. If neither one asks, neither one gets the answer.”

“People who are passionate about their work are all about sharing. That’s part of the scientific journey. What you learn, you want to give back, and you want to bring somebody else along with you. So don’t be afraid. I always say there are three possibilities when you ask a question: a yes, a no, or a maybe. Stay positive and see what you can learn.”

“And if they say no, go to the next person. Some people get so caught up in their own narrow world that they forget somebody helped them get where they are. You should help somebody else get where they can go. It’s all about helping.”

More questions than answers

It’s easy to assume a successful person’s path was smooth. What setbacks did you have, and what kept you going?

“I’m an eternal optimist. When you do research, you end up with more questions than you started with. You have a hypothesis, you get partway down the road, and all of a sudden it’s, ‘Why don’t these results match what I thought?’ It can slow you down. But maybe there’s another path, or another story to learn. I try not to dwell too long on a setback before I go discover something else.”

What do you wish you knew at 15 or 16? Would you take the same path again?

“The path is not straight. It has twists in it. But I’ve always felt that if I’m moving forward, I can keep hope and keep building.”

“I’ve been at Prairie View for 35 years, and I’ve gotten to see a second generation of students. I have a young lady in class whose father was also my student. I never knew that would happen. My wife tells me I can’t retire, so I tell her that as long as I’m enjoying the work, I’ll keep doing it. I’m an outdoors person. I can only stay inside so long before I’ve got to go outside.”

Never call it dirt

“My mother, who’s passed on now, could never believe they actually pay me to play in the soil. And in soil science, we never use the D word. It’s a four-letter word. We have an equation: soil is not equal to dirt. Dirt is soil out of place. The soil under our feet gives life to plants, to animals and to us. So we value it.”

The science under a football field

When I said most of us walk on grass every day without thinking about what’s under it, he told me about turfgrass researchers at Texas A&M.

“They take plugs out of golf courses and athletic fields and look at the grass and the roots to find disease and drainage problems. On some fields they even put plastic mesh into the soil to make it more cushiony. Think about how valuable athletes are to their team. You want them on a surface that gives back a little when they touch it, or fall onto it.”

Last thing

Is there anything else you want the teens watching to know?

“Find your passion. Find the thing you’re interested in, and keep learning as much as you can. If you can turn it into a career, you’ll find out time flies. I look back and it’s been 35 years, and it’s been an amazing journey.”

Thank you to Dr. Griffin and Prairie View A&M University for making the time.

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