SALT LAKE CITY – Salt Lake City schools are saving thousands in maintenance costs thanks to some kids, and probably a few bucks and does, as well.

Washington Elementary School officials are contracting with 4 Leaf Farms for the third year to employ a herd of goats to manicure the tricky terrain on campus, which typically costs about $8,000 for a landscape crew to clear out the vegetation, KUTV reports.

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The goats do it for about $3,000.

“We’re not hurting bees we’re not hurting birds, it’s just a natural thing that’s been around for thousands of years,” 4 Leaf Farm’s Greg Cover told the news site. “They’re the most efficient worker you’ll ever work with. They don’t complain. They don’t talk back. They don’t take breaks. They just go to work.”

“The terrain here is difficult to work on,” Salt Lake City custodial supervisor Ricardo Zubiate said, adding that officials have concerns about chemicals and mower emissions to remove the vegetation on the steep hillside next to the school.

“Using goats is just the right, natural way to do it,” he said.

Cover said 4 Leaf Farms employs about 400 goats to clear out both large and small plots in the area by fencing in the animals for several days and letting them do their thing.

The area around Washington Elementary, he said, should take about a week to clear out.

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“It looks like it’s been weed whacked” once the goats are through, he said.

“They just go, and go, and go,” Zubiate said.

Salt Lake City schools, of course, aren’t the first to contract with four-legged landscapers. Officials in the Lawrenceville School district use dozens of sheep from Cherry Grove Farm to groom grass around the solar plant that helps power the district’s schools. The sheep help to keep the area natural, while saving thousands in landscaping costs to maintain the 30-acre site, EAGnews reports.

But not everyone loves the idea, especially the unionized school employees who are now missing out on the work.

Western Michigan University hired a small goat crew to clear out a woodlot this summer, but the school now faces grievance filed by the local American Federation of State, County and Municipal Employees, the union that represents WMU’s maintenance workers.

“AFSCME takes protecting the jobs of its members very seriously and we have an agreed-upon collect bargaining agreement with Western Michigan,” union president Dennis Moore told the Lansing State Journal. “We expect the contract to be followed, and in circumstances where we feel it’s needed, we file a grievance.”

The union alleges WMU officials did not notify the union about the competing crew coming in.

Regardless, university spokeswoman Cheryl Roland said the goats better suited for the job. A crew of about 10 goats successfully cleared out a lot on campus last summer, and a 20-goat crew is now working to clear 15 acres of tough terrain before students return in the fall.

“For the second summer in a row, we’ve brought in a goat crew to clear undergrowth in a woodlot, much of it poison ivy and other vegetation that is a problem for humans to remove,” Roland said. “Not wanting to use chemicals, either, we chose the goat solution to stay environmentally friendly.

“The area is rife with poison ivy and other invasive species, and our analysis showed the goats to be a sustainable and cost-effective way of removing them,” she said.

Nicholas Gooch, a WMU horticulturalist who manages the goat project, told the Journal the goats are performing better than expected so far this year, but the union grievance is throwing a wrench in an otherwise perfect solution.

“It’s definitely not what we hoped would come out of this project,” he said of the AFSCME grievance. “It kind of takes the air out of your sails a little bit.”