They go back and forth to take down the grasses square foot by square foot as Dremann uses hand signals to guide the crew above the noise of the trimmers like a conductor directing an orchestra.
The work goes on for up to eight hours at a time, with the crew lugging their 25-pound trimmers across the meadow.
Kite Hill, between the Glens neighborhood and I-280, used to be alive with wildflowers and native plants centuries ago, Dremann says.
But when the Spanish explorers and settlers landed in California they brought their livestock with them. The livestock had eaten hay that contained seeds from weedgrasses that originated in Europe, he explains.
Within three generations, the weedgrasses took over the fields where the native plants once thrived burying the plants underneath them.
During summertime the weeds dried up and turned brown, creating fuel for the type of devastating wildfires that we're experiencing today, Dremann says.
Meanwhile, the native plant seeds lay dormant beneath the soil waiting for their opportunity to emerge.
The string trimming tops the weedgrasses and kills their seeds so that within four or five years they're completely wiped out, allowing the wildflowers to reappear, he explains.
Woodside's Kite Hill is now ablaze with Tidy Tip, a member of the daisy family, which has white and yellow flowers and dozens of other multi-color blooms..
"A botanist who said he has been observing the plants on Kite Hill for 59 years said it was the best blooming he had seen in all the years he's been observing," Dremann says.
The Kite Hill project got started four years ago, helping the expanse of land to go from 90% non-native to 95% native with 100 species of wildflowers, Dremann says.
He says he's "unearthed an entire ecosystem" in the soil below as purple Owl's Clover, Miner's Lettuce and other natives have bloomed, replacing the grasses that have largely been wiped out.
"On the Peninsula, it's like ecological ruins restoration, restoring a system that's been around for millions of years," he says. "The nature preserve will be wiped out if you continue to let the weeds expand their territory."
Dremann's interest in plants began when he started a garden at his home in Redwood City at 4 years old.
When he was attending Sequoia High School he got a job a doughnut shop so he could raise the money to start his own vegetable seed business.
The interest in native plants came from being near open space at his home in the Redwood City hills. "I looked around in the '70s and '80s and thought about who is looking at our native plants, and the answer was nobody," Dremann says.
Now an East Palo Alto resident, Dremann began researching on his own about how to eliminate the weedgrasses, using small plots to try different techniques before perfecting his method.
In the meantime, he worked as an ecological restoration consultant for various agencies, including the California State Transportation Authority and the U.S. Forest Service.
Volunteers from the neighborhood had been pulling up the invasive Yellow Star Thistle that had been growing on Kite Hill more than 10 years.
The residents didn't know how to get rid of it, so they approached the town about the problem.
"Woodside decided to go in a native plant bent," explains Frank Manocchio, a Woodside maintenance contractor who supplies the labor and works with Dremann on the project. "When our test plot was successful, they OK'd us to move forward on Kite Hill."
"I know the neighbors are thrilled," he adds.
Dremann is being paid about $10,000 a year for his work from the town's general fund, and Manocchio is paid by the private Woodside Community Foundation, according to Town Manager Kevin Bryant.
"I think the project has been fairly successful," Bryant says. "People were volunteering their time, and it wasn't really working, and we very quickly thought there was a better way to go about it."