Thousands of motorists, cyclists, runners, and rowers pass the historic Laurel Hill Cemetery in Philadelphia that rises 45 feet atop a steep slope overlooking Kelly Drive — the graveside monuments and headstones poking out from above as if guardians of the Schuylkill below.

Starting next week, that one-acre green slope at Kelly Drive and West Hunting Park Avenue will start turning brown as it gets defoliated with herbicides and by hand. The goal: Create a new meadow the cemetery’s owner believes will be more natural to the area, result in a haven for native bees and birds, help with erosion, and give passersby a more colorful view. Plus a granite outcrop that gives a commanding view of the river will be exposed for the first time in decades when ivy and other vegetation are gone.

“It’s a very unusual project. And we want to make sure the public is aware of what we are doing,” Nancy Goldenberg, president and CEO of Laurel Hill Cemetery, said during a walk Tuesday along the base of the slope. “I see thousands of people driving by or biking here every day. And this could all be gorgeous.”

Goldenberg fears some might think there’s been an ecological disaster when they see the denuded hillside, which she said will be replaced with “a new meadow of native flowers and shrubs.” They’ll leave native trees intact.

What is Laurel Hill Cemetery?

The project might seem unusual for a cemetery, Goldenberg said. But she notes Laurel Hill is a registered arboretum because of its 78 acres of manicured grounds in East Falls. Established in 1836, the nonprofit Laurel Hill is the nation’s first National Historic Landmark rural cemetery. Its founder, John Jay Smith, a Quaker, planned for horticulture to play a key role. Laurel Hill was also designed as a park and is open to the public.

The cemetery contains 30,000 monuments and headstones for some of Philadelphia’s most notable families from its industrial past, as well as Phillies broadcaster Harry Kalas, Civil War Gen. George Meade, and Sarah Josepha Hale, the poet who wrote “Mary Had a Little Lamb” and was instrumental in creating Thanksgiving as a national holiday. It even has a headstone used in Rocky Balboa for the fictional Adrian Balboa, wife of the movie boxer.

The cemetery’s sister cemetery, the 187-acre West Laurel Hill Cemetery, lies across the river in Bala Cynwyd. The two cemeteries together are registered as one arboretum.

Why are they removing all vegetation?

Laurel Hill Cemetery hired Larry Weaner Landscape Associates based in Montgomery County to design the meadow and the Texas-based contractor Resource Environmental Solutions to carry out the work, which is funded by a state grant.

It will take several applications to eradicate the existing vegetation — a mix of native and invasive species. The cemetery is split in half by West Hunting Park Avenue. The slope across the road will remain as is for now but could also be turned into a meadow if the first effort is successful.

Larry Weaner Landscape Associates says the current mix of plants has “little ecological value” and will be replaced with seed mixes “that will highlight distinctive viewsheds and unique areas” while bringing a cohesion to the landscape. That entails composting the site first, then putting down a mix of native grasses (sedges and rushes) and wildflowers.

Seeds include nodding onion, butterfly weed, fox sedge, purple coneflower, foxglove beardtongue, mountain mint, and smooth blue aster.

The resulting meadow should change over the seasons, while helping with erosion, conservation, and beautification of Kelly Drive, the landscape firm says. It will support species of butterflies such as swallowtails, monarchs, and painted ladies. It will attract and provide habitat for honeybees, bumblebees, miner bees, and mason bees, as well as birds such as the red-throated hummingbird and eastern goldfinches.

Mike McGraw, a wildlife biologist, and Jessie Buckner, an ecologist, both with Resource Environmental Solutions, are helping implement the design. They met Goldenberg at the slope as they surveyed for insects and birds to form a baseline of existing wildlife.

“Overall, this landscape is low-performing from an ecological perspective,” said McGraw as he pointed out various species of vegetation and noted a 200-or-so-year-old oak tree on the slope. “This is not diverse at all. The only thing you have good going for you here are these amazing trees. You have this gorgeous red oak. It’s stunning.”

McGraw said that Philly, because it is so old and one of the first big cities in America, was “ground zero” for what now totals about 150 invasive plants in the area.

McGraw noted that he had just seen a Baltimore oriole and its coloring was pale. He said that with a more abundant food supply provided by the meadow, orioles will become a more “blazing orange” as they seek mates.

What’s involved in stripping the slope?

McGraw said the use of herbicides, such as glyphosate and triclopyr, would be applied in a “surgical” way, and not just sprayed like a “fire hose.” There will also be a lot of weed-pulling by hand.

Buckner said the hillside is “not as stable as it could be” and needs to be shored up.

“So there’s an erosion and sediment control plan,” Buckner said, noting that storm runoff will be better captured in the new root systems, increasing nutrients in the soil.

Buckner said that after all vegetation is removed, crews will install filter socks around certain areas. Filter socks are tubular mesh sleeves filled with compost and used to control runoff and filter storm water. Crews plan to blow a compost across the slope that will get topped with a coconut fiber matting to hold it in place. That matting will be seeded in the fall and eventually disintegrate after the seeds take root.

The new meadow should start to emerge by spring.

When asked why Laurel Hill was putting so much effort into the meadow, Goldenberg, Laurel Hill’s president, thought for a moment.

“We’re not just a cemetery,” she said.

This article has been corrected to note that sumac will not be removed.