The entire crew is ready to start working, but Gladys is being a prima donna. It's the exact opposite of the movie star cliche: Gladys refuses to get into her trailer. She has a point. It's late July, her trailer has no air conditioning, and it's full of goats.

Gladys is also a goat, though she’s shorter and lumpier than the others in the herd, like a corgi among deer. She’s got one horn and a King Tut-style beard. Her objections are noted, but supervising forester and Eco-Goats owner Brian Knox carries her into the trailer with the rest of the team — which is on its way to work. These are professional goats; they are hired to eat excess vegetation. This crew — 25 of the 28 goats in the herd — just finished a job yesterday, and now they are setting out from their home at Where Pigs Fly Farm in Centreville, Md., for another gig, just over the border in Delaware. The trailer has a trough of grain, just in case someone needs a snack on the way to the food.

Eco-Goats made a big splash in August 2013 when its goats were hired to eat vegetation at Congressional Cemetery in Southeast Washington. It was a slow news week (slow news weeks are things that used to happen), and the media went crazy for the goats. There’s a little bit more to the story, though. In the past decade or so, the Washington region has grown from one goat-landscaping business to at least five within about a three-hour drive. Besides Eco-Goats, there’s also Browsing Green Goats, Glorious Goats, Harmony Church Farms and Goat Busters.

Mary Bowen at Browsing Green Goats, who started with 15 goats in 2010 and now has 75, says the business grows bigger each year. She’s booked all season, April through November, for private yards and public areas.

Knox, who also works in conservation consulting, started Eco-Goats when a client of his bought goats nine years ago; the client — after spending time with the goats — lost the stomach to raise them for food. The business grew to 140 goats with work seven days a week, though it has since downsized to 28 and a more relaxed schedule. When I asked him the secret of Eco-Goats’ success, he said it was a lack of competition. They seem to have all the work they want.

So why is there so much demand for goat grazing? For consumers, there’s still a novelty factor and the constant search for ways to be greener. Goats do emit methane, a greenhouse gas, but — unlike machines — they don’t consume fossil fuels. And as Jenny Gardiner, a satisfied customer, wrote in the Charlottesville Daily Progress in 2013, watching “goats munching away at ugly weeds has been downright soothing.”

For entrepreneurs, meanwhile, the barriers to entry are low — if, that is, you happen to have access to a herd of goats and some land. (Vet bills can be the biggest expense, Knox says.) Often, you don’t need a permit to let them chow down on an overgrown field. And the District recently loosened regulations on goats in the city. Previously, it had only allowed the animals for special events and educational purposes (a loophole Eco-Goats used for Congressional Cemetery).

At the Eco-Goats work site in Delaware, the herd stays in the trailer, while Knox, chief shepherdess Jennifer Vaccaro and Vaccaro’s nephew Mason mark out the border inside which the goats will graze for the next four days. They’ll put up a portable electrified fence, but first Knox has to use a chain saw to carve out where the fence will go. The client originally asked about clearing five to six acres, but only about a third of an acre is suitable for the goats.

This is typical, according to Vaccaro. People want goats, even if they’re not suited for the terrain. “People hear about goats, and goats are fun,” she says. “Probably 90 percent of the time we say, ‘This is not an appropriate job for goats.’ ” The animals, for example, prefer not to eat plants low to the ground, such as grass or English ivy. If they do, they could get parasites.

The idea is to clear the invasive plants and leave the vegetation the customer wants to keep. Knox tells me about a time when they told a client: “I’m sorry, we’ve got all this good stuff in here, we’re not going to graze it anymore.” And the customer complained: “I want my goats.” Vaccaro picks up the thread: “ ‘I want to be the neighborhood goat lady!’ Sorry.” There is, in short, goat demand that will not be met.

Using goats to clear land “is way more labor-intensive than anyone can imagine,” Bowen says, adding that she doesn’t work on plots of less than half an acre anymore. At Eco-Goats, the humans will step in with tools when the job is not goat-appropriate. Still, it’s the goats that get the clients in the door. “We think of them as our marketing department,” Vaccaro explains.

They are also, in a sense, the perfect employees. They love their work, and they don’t take bathroom breaks but go right where they’re eating, while they’re eating. Even that is good for business, enriching the soil. They’ll eat their way through their plot of land efficiently — section by section, as a team. Knox says his herd of 28 can clear an acre of brush in 10 to 12 days. Eco-Goats charges $2,500 to $3,000 per acre plus expenses.

Gladys and the other goats seem happy enough in their trailer, or at least quiet and still. They huddle together even though it’s hot. One goat scratches her face using the point of another’s horn. They have strange horizontal coin-slot pupils. I ask if there’s a scientific name for that. “Crazy goat eyes,” Knox says.

For more than an hour, the three humans dig postholes in the hard dirt, put up a fence and prepare the goats’ meal. The goat-grazing business, says Vaccaro, is “hot, sweaty, dirty, buggy work.” It’s midday, and she and her nephew are in rain boots to protect against chiggers.

The herd makes a little money, Knox says, but it’s not a living on its own; profit margins are thin. Yet there are forces other than capitalism at work here. Knox says the mission is more about forestry rather than all the work the goats can get. Eco-Goats recently had one of its goats de-bucked because 28 goats seemed like enough, and, Vaccaro says, they couldn’t bear to sell kids after seeing how mothers and babies will stay together as companions even after the kids grow up. Says Knox: “They’re too much like family.”

Rachel Manteuffel is a Post editorial aide.