Usually in the suburbs, it's development replacing farmland, not the other way around.

But a new corporate headquarters proposed for the site of a onetime trucking terminal near Interstate 35W has the city of Roseville wrestling with the prospect of actual agricultural work taking place near a lake and a city park.

And it prompted one company official to make a promise to elected officials at a recent City Council meeting that the new facility won't lead to farm combines with 50-foot wingspans lumbering through city streets.

Negotiations center on a proposal by a New Brighton firm called Calyxt Inc., an ag biotech company that aims to create healthier food products. The plan calls for greenhouses and "up to five acres of outdoor research plots," near Roseville's Langton Lake Park.

The proposal has led to fear of heavy equipment damaging city streets and farm chemicals carried by the wind.

Council Member Tammy McGehee told company representatives last month that the proximity of University of Minnesota farm campus fields led to hard-fought regulations requiring, for example, warnings posted and left up "for the duration of the toxicity of the pesticide."

Pleased to have landed a corporate headquarters that promises to employ as many as 100 people on what is now a vacant industrial site, Roseville council members have seemed eager to avoid shackling Calyxt to burdensome conditions.

Council Member Bob Willmus, for instance, objected to language aimed at preventing wear and tear on city streets.

"Any homeowner can drive a small tractor on a street," he said. "This seems overly restrictive."

B.J. Haun, the company's director of product development, assured city officials that they needn't be concerned about large, destructive equipment.

"Five acres is a big garden, essentially," he said. "There will be no 16-row combines with wingspreads extending 50 feet outward going down your streets."

He said Calyxt intends to follow U protocols and will "actually apply less chemicals and fertilizers than most people do to their yards."

The firm is engaged in producing such advances as lower saturated fat canola oil, lower trans fat soybean oil and wheat with less gluten, according to its website.

City officials did caution, in a December special meeting devoted mostly to the subject, that the firm is expected to seek financial help in the form of tax-increment financing before the deal is done.