♪♪ This west Texas field may not look like a university laboratory, but the agricultural research on these 44 cotton plots in San Angelo, Texas, could dramatically reduce the need to use chemicals to fight weeds.

Don't look for researchers in white lab coats here.

Instead, these sheep, in their own wooly white coats, are the focus of the research.

[Reagan Noland] We've got certain weed species that are becoming very problematic, and a lot of these are very palatable for sheep.

And so, the logic here is that sheep will graze the weeds in the cotton before they eat the cotton.

And so, we approach this, um, for one, kind of as proof of concept, because this has never been documented in a scientific research project- running sheep in a cotton crop as a method of weed management.

♪♪ Moving their wooly assistants from corral to the field lab, Dr. Reagan Noland and student Matt Stewart are testing two of the research variables: timing and intensity.

At what stage of cotton growth do you start weeding with sheep?

And how long do you keep the sheep in the crop field?

Having this many plots helps researchers better test those variables.

The good news?

As the sheep do their weeding work, they avoid eating the cotton plants because the plants themselves contain a toxin that sheep find less than tasty.

[Reagan] They're keeping the cotton a lot cleaner.

So, it's exciting to see the contrast between the weedy plots and those that we're running sheep in.

Texas leads the nation in cotton production and raises the lion's share of organic cotton grown in America.

That share has grown in recent years, thanks to higher prices for the organic fibers.

Add to that, consumers preferring the "feel" that organic fibers deliver in clothing and they like products raised without the use of chemicals.

But foregoing chemical herbicides to control weeds has been a challenge, along with protecting the soil for future crops.

[Reagan] When we get into sustainability, this is a big factor.

So, a lot of cotton weed management is tillage-intensive, especially in an organic system where they can't use herbicides.

And so, they're plowing a lot.

They're burning a lot of fuel and they're disturbing the soil quite a bit to manage those weeds.

And then, what weeds they don't catch with a cultivator, they're hand weeding or they're not being able to control them.

[Chad Raines] You... You look through here and the only weeds that are out here are right here, where the cotton is.

So, we can't get it with any type of mechanical plow.

In addition to the Texas A&M University research, sheep rancher Chad Raines is using 145 of his animals for "real world" weed control in this West Texas organic cotton field owned by a neighbor.

Dr. Reid Redden, a sheep specialist, is following the results.

[Reid] Which of these weeds, um, do you see the sheep really selectively go after?

[Chad] You know, it's kind of like on my cover crops.

The sheep, they... they like the variety.

[Reid] We need the basic science.

We need the people in the lab generating, you know, new and novel technologies that you'd never really think of, uh, but we also need the applied people.

Growers and ranchers say there are mutual benefits to sheep weeding.

Seth Fortenberry owns the organic cotton fields being used by Chad Raines.

The weeds provide forage for Chad's sheep, keeping his feed costs down, and Seth eliminates a cost he's faced in the past.

[Seth] We'd mainly just had to hire labor.

You know?

I mean, people to go out there and weed the fields manually, and these sheep, you know, are obviously- they work 24/7, you know, all the time.

I mean, you don't have to worry about them showing up.

You don't have to worry about paying 'em.

I mean, you know, they... they just are good workers.

With organic cotton fetching higher prices than non-organic, farmers say that sheep weeding can deliver savings, economically and environmentally.

[Chad] A lot of our land is family land.

It's been in my family for generations.

I want to take care of it, and sustainable, for me, is that I'm doing...

I'm doing my job.

I'm taking care of it.

It's going to last.

It's going to be here for my kids and my grandkids, and... and, uh, it's, you know, it's still going to be productive.