An overflow crowd piled into the Scott County government center Thursday night to object to a plan that calls for a slow extinguishing of farming in the decades to come as a human flood gradually converts most of the county's western portions into suburbs.

"Is there anyone in this room who doesn't eat?" asked Dave Minar, of Cedar Summit Farm, at the county's southern end. "I am hearing about 'public values,' but preserving ag land isn't one of them. It's hard for me to understand."

The county was staging a key public hearing in the closing stages of a four-year process to update its long-range plan.

"Trends in agriculture have changed dramatically towards a demand for locally grown food," said Jennifer Jensen, a spokeswoman for a small grass-roots group called the Local Harvest Alliance. "There are concerns over food safety, reduced fossil fuel usage, farmland preservation, better nutrition and strengthening local economies, to name a few."

The plan envisions Scott County, until recently a thinly populated rural outpost, becoming a major population center during this century, with as many as a half-million residents at full build-out.

That's about four times as many people as live there today.

It permits much of the eastern side of the county to remain the sort of "10 acres and a horse" area that it has become. But it seeks to block that from happening in most of the west, while envisioning that most of that area would convert from farms to subdivisions.

It does set aside a portion of the southernmost part of the county as permanent farm country -- all of Blakeley and Belle Plaine townships, and portions of two others, Sand Creek and Helena.

But it assumes a deal under which the Metropolitan Council builds a big new sewer plant south of Shakopee, in return for the county setting aside a vast area for eventual suburbanization.

But a procession of speakers Thursday night asked planners to reconsider.

"In three days I found 349 people willing to sign a petition to save farmland in Scott County," Mark Jensen, Jennifer's husband, told the county's planning advisory group. "Five declined. Please take that under advisement."

Ann Houghton, who farms in the southern portion of the county, pointed to surveys showing what people in Scott County want.

"The vast majority of the public wants a rural atmosphere and small-town lifestyle," she said. "We need to take more proactive steps to maintain that. But instead we see preservation of farmland labeled as a 'strategic challenge,' rather than a goal."

Other speakers offered support for the plan, noting that especially with the slowdown in housing, farming areas can expect to remain untouched for most peoples' lifetimes.

Given the relatively tiny number of farmers remaining in Scott County -- just one in 100 working-age people in the county, according to the latest census estimate -- growth objections may be the strongest political hand the opponents can play.

It is clear from public surveys commissioned by the county itself -- most recently in 2006 -- that the county's rapid rate of growth and development are a growing source of irritation to residents. The fact that many of them are, themselves, recent arrivals, doesn't keep them from describing further growth as the biggest problem the county faces: five times more serious (48 percent fingering it as such) than the next-highest candidate, taxes (10 percent).

The county's plan only covers the county's rural townships. The cities are creating -- or technically "updating" -- their own plans for the period through the year 2030.

Thursday night's meeting began at the dinner hour and was still going strong well past 9 p.m. It is the last major public hearing on the document, though there is a public meeting expected for summer.