The road turns to gravel just past the front gates, rattling teeth and dashboards alike to enforce a de facto speed limit that keeps traffic from moving much faster than a wild buffalo.

The bumpy ride eventually leads to the Tallgrass Prairie Preserve "headquarters," where the bathrooms are relegated to a separate building on the other side of the parking lot, and docents can wait all day to see just one visitor at the gift shop.

Obviously, the Prairie Preserve isn't trying to be a major tourist attraction.

Tourists come anyway - more than 20,000 of them a year.

"But for us, it's not about the visitors," says Bob Hamilton, who was part of the Nature Conservancy's original effort to establish the preserve and still serves as its science director. "It's about the grass."

A short drive from headquarters, Hamilton pulls his pickup off the road near one of the few barbed-wire fences that still cross the preserve .

On one side of the fence, the yellowed grass stands waist-high, but on the other, it barely reaches his knee.

"And, yes," he says, "the grass is always greener on this side."

More than 2,700 head of roaming bison keep it freshly mowed.

Most visitors come to see them, not the grass. But conservancy officials are fond of saying that the grass isn't here for the bison; the bison are here for the grass.
As the Prairie Preserve begins to celebrate its 20th anniversary this month, everything is still ultimately about the grass.

"This place is about conservation," Hamilton says, "not tourism."

It wasn't always going to be that way.

In the mid-1980s, the federal government was planning to buy up thousands of acres of virgin grassland in Osage County to open a new national park, a kind of "Yellowstone on the prairie."

With it, presumably, would've come paved roads, hotels, campgrounds and other developments that always spring up near a national park.

"It probably would've been a bigger economic asset for the local economy," Hamilton says. "I think it's an interesting 'what if.' "

Instead, the effort fell short in Congress, and, in October 1988, the Nature Conservancy stepped in with Plan B: The conservancy itself would raise $15 million to buy the land and create an endowment to fund a privately owned preserve.

At the time, it was the largest capital campaign ever launched by the conservancy. And the plan seemed particularly ambitious, considering that the Oklahoma chapter was only 2 years old.

"I'm sure there were some people," Hamilton says, "who doubted we could do it."

The conservancy took possession of the historic 29,000-acre Barnard Ranch on Nov. 8, 1989, which is considered the preserve's birthday.

"I like to think of the last 20 years as our startup phase," Hamilton says. "Now that we're settled in, we can really get to work."

The next 20 years, offi cials say, will involve "moving conservation off the preserve."

The preserve itself has grown to 39,100 acres. But that's only a fraction of the 3.8-million-acre region known as the Flint Hills, straddling the Oklahoma-Kansas state line with the largest remaining patch of tallgrass prairie on the continent.

"We think of the preserve as an incubation site," Hamilton says, "for encouraging conservation across the wider area."

Toward that goal, in recent years the preserve has developed a sophisticated system of controlled "patch burns" to mimic the role natural grass fires used to play on the open prairie. Hamilton hopes to see the practice spread like wildfire, so to speak, across private ranches in the area.

"Fire is a big part of what we do," he says. "Take away fire, and in a generation or two, the prairie will turn into a woodland."

Along with patch burning, private landowners could adopt methods of "conservation grazing" that are being develo ped on 12,000 acres set aside for domesticated cattle, to show how ranching can coexist with natural tallgrass.

Hamilton also wants to expand the use of "conservation easements" across the entire Flint Hills region, offering landowners financial compensation for agreeing to give up the right ever to disturb the natural tallgrass with plowing or development.

Easements might prove to be the most effective way to fight wind power, which Hamilton expects to become a major threat to the natural prairie over the next few decades.

While wind power generates clean energy, the vast networks of turbines, roads and power grids can disturb a natural ecosystem just as much as any other industrialization, Hamilton says.

"I think the next 30 or 40 years will be decisive," he says. "Whatever land that is going to be set aside for conservation will be set aside by then, and the rest will eventually be lost forever."

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