In 1990, the estimated number of Community Supported Agriculture (CSA) farms in the United States was 50. Today, according to Wikipedia, there are estimates as high as 3,000. Wisconsin alone has over 100.

With more and more people looking for a low-carbon diet, the interest in CSA's model of food production is rapidly growing.

Simply put, the system connects local farmers with local consumers who become members or shareholders of the CSA by financing the farm's whole seasonal budget, including seeds, tools, maintenance and land payments. In return, they get weekly or monthly baskets of fresh, organic produce, fruits, flowers, herbs, eggs, milk -- anything the farm produces.

Pinehold Gardens, a 21-acre CSA farm in Oak Creek, has been an active CSA since 1995. For the past seven years, owners David Kozlowski and Sandra Raduenz have participated in the CSA and Local Farmer Open House at Milwaukee's Urban Ecology Center, 1500 E. Park Pl. in Riverside Park.

This year's is happening Saturday, March 7 from noon to 4 p.m.

Every year a couple dozen Wisconsin CSA farms and farmers converge to educate the community about the importance and impact of buying local foods. Kozlowski says CSA membership has quadrupled since the event launched in 2003.

Still, there are many people unaware of how CSAs work and how much food can be sourced locally. And it's more than just boxes of fruits and vegetables -- it's easier now than ever to buy meat and dairy from local farmers. That is the No. 1 message at annual open house.

"Second is help educate people on growing practices, particularly those practices that don't include chemical fertilizers or pesticides," says Kozlowski, who has helped organize the event for the last four years.

"There is considerable emphasis placed on the quality of local food and how to prepare, preserve and store the abundant produce that is available in southeastern Wisconsin in the summer. We have always wanted the open house to be an event that brings families together around food and farming. Even if no one decides to participate in the effort to buy local food, we still consider the event successful for anyone who walks away with fresh perspective on farms, farming and food, and who has had the opportunity to talk with people who do participate."

The event is free and features activities for kids and door prizes totaling $600.