There's a tough new rule in the Skagit Valley's never-ending struggle to preserve farmland. From now on, you won't be allowed to build a new house on land zoned for farming, unless you're a farmer. Not a make-believe farmer, but one actively making a living from the land.

Under the new rules, when you apply for a county permit to build a house on farmland, you sign a sworn affidavit showing three years of farm income from the lot where the house would stand. And forget about nesting there as a non-farmer while renting the tillable land to someone else. If you're going to build on it, you'll have to farm it yourself.

Skagit County has had the latent authority to do this for ten years, but Planning Director Gary Christensen says the language of the code, until now, was too imprecise to enforce. So the astonishingly productive lands of the Skagit Valley, listed by agronomists as among the best in the world, are becoming home sites.

There's been a 40-acre lot-size minimum in the Skagit ag zone for years. But as Christensen explained to the Skagit Valley Herald, the agricultural parcels "can in the end turn out to be large-lot residential parcels on which maybe McMansions are built."

Planners in Pacific Northwest farming counties are learning now what those in the farming states of the Eastern Seaboard found out 40 years ago &mdash zoning land for large minimum acreages does not necessarily stop sprawl. It simply changes one-acre sprawl to five-acre sprawl, or in the case of the best Skagit lands, 40-acre sprawl. So regulations meant to protect farmland can make it disappear even faster.

Every region of the country faces Skagit County's dilemma. A study by the American Farmland Trust six years ago found the United States losing two acres of farmland to development every minute. In the course of a year, that amounts to an area more than half a mile wide that would stretch from San Francisco to New York.

Christensen's new interpretation doesn't change the rules for those who want to remodel or rebuild an existing house on an agricultural lot. It's aimed at stopping new building on ag lands by non-farmers, and reflects an extraordinary passion by Skagit Valley residents to hold onto what's left of agriculture.

Kenny Johnson, a retired dairy farmer who serves on the Skagit County board of the Washington Farm Bureau, thinks the new rules could help save agriculture. It isn't just the literal conversion of farmland from growing crops to growing houses that worries him. It's what happens to the price of land. "Some very well paid executives with plenty of money to invest, they can pay $20,000 an acre more than a farmer can," Johnson told Crosscut. "With us, the land has to pay back our investment. These guys buying it up just for a place to live, they don't have to worry about that."

Johnson and other farmland advocates worry also about the critical mass of farmers. Once the number of farms in a given community drops below a certain level, farm-related businesses go away. Soon there are no machinery dealers, dairy processors, truckers, seed and fertilizer dealers. It's next to impossible to farm without those supporting businesses, and once they've gone, farmers begin to give up.

Johnson sees one major problem with Planning Director Christensen's new enforcement tools — the provision that disallows the 40-acre homeowner to rent his unused land to someone else. "They say you have to farm it if you're going to build on it," Johnson observes. "That really means a neighbor can't rent that farm land that isn't being used. I'm afraid that's wishful thinking. Farmers here are always looking for other land to rent. I don't see how they're going to enforce that."