With chainsaw in hand and his climbing rope tethered to an oak tree, Jake Froyum inched his way down the cliff near Minnehaha Falls Wednesday morning. As he cut buckthorn brush that sprouted from ledges, a torrent of water poured over the falls a short distance away.

Froyum applied some finishing touches on a $300,000 job by Prairie Restorations Inc. to remove invasive plants and help restore the environment at one of the area's most popular and best-known sites.

Working on contract with the Minneapolis Park and Recreation Board, crews have cleared several thousand trees and burned dozens of piles of brush in 54 acres of the lower glen of Minnehaha Park. The work is part of a bigger $7 million makeover for the falls area that began in 2008.

"People will notice that the walls are no longer crumbling, the stairs are in better condition, and that the bridges are much improved," said Park Board Commissioner Anita Tabb.

The clearing work began in November, got snowed out until late February, and will finish this week. The glen is a narrow valley extending three-fourths of a mile from the base of the falls to the creek's confluence with the Mississippi River.

"So many of these sites around the metro are just overgrown," said Prairie Restorations President Ron Bowen. Invasive honeysuckle, garlic mustard, buckthorn and Siberian elm choke ground-level wildflowers and grasses, he said, reducing the diversity of insects, birds and other wildlife that were far more common in the glen years ago.

Removing the vegetation will also give the area a more open feel, with better sightlines and vistas, Tabb said.

Nearly $3 million for the falls-area projects came from state bonds authorized by the 2008 Legislature, Tabb said.

Near the falls, a dozen workers worked across the steep slopes, pulling brush into piles and dousing them with diesel drip torches to burn. Project manager Mike Hiltner directed a worker to cut down an half-dead elm and a poorly formed hackberry, but not to damage a couple of healthier trees on the slope.

"We've taken a few thousand full-sized mature trees out of here, and everything's been taken by hand," Hiltner said.

Nearly all of the work was done on frozen ground to minimize damage to plants and soil, he said, but the steepest slopes near the falls were too treacherous until the ground thawed.

The next stage begins in a few weeks with replanting of species such as columbine, wild geraniums, prairie phlox and little bluestem grass.

Toni Youngman, a Richfield resident who grew up in Minneapolis, looked down from the top of the falls at the rampaging creek below.

"You can see more of what's actually down there, and it might also be safer," she said. "It's a fabulous park. I've been coming here since I was born."

Tom Meersman • 612-673-7388