MADISON, WIS. – Rod Nilsestuen, 62, the head of Wisconsin's Department of Agriculture since 2003, drowned on July 21 while swimming in Lake Superior after spending the day volunteering with a church group building a Habitat for Humanity home in Marquette, Mich., according to The Associated Press.

On July 22, shocked and saddened associates described him as a tireless advocate for Wisconsin agriculture, instituting groundbreaking animal disease identification requirements, helping to bolster cheese and milk production and pushing to preserve farmland for future generations.

According to police reports, Mr. Nilsestuen went for a swim after dinner on Wednesday and was seen struggling after a wave pushed him away from a sandbar near Picnic Rocks, a recreation area along the lake in Michigan's Upper Peninsula. Mr. Nilsestuen tried to get back on the sandbar but couldn't, witnesses told police. He was removed from the lake less than an hour later and pronounced dead at a hospital after attempts to revive him failed, police said.

Gov. Jim Doyle (D) chose Mr. Nilsestuen to be his first secretary of the Department of Agriculture, Trade and Consumer Protection in 2003. Before that, Mr. Nilsestuen worked for 24 years as leader of the Wisconsin Federation of Cooperatives, now known as the Cooperative Network. He was also involved in creating the Wisconsin Milk Marketing Board and recently oversaw passage of a new program called the Working Lands Initiative that offers tax credits to help keep agricultural land available for farming.

During Mr. Nilsestuen's tenure, Wisconsin became the first U.S. state in 2005 to make mandatory the identifying of farms exposed to foreign animal diseases. That system was seen as a national model.

Gov. Doyle credited Mr. Nilsestuen for dramatically increasing Wisconsin's production of cheese and milk, promoting the development of biofuels to generate local renewable energy and ensuring that "farmers received the economic value of their work." Mr. Nilsestuen was raised on a dairy farm near Arcadia started by his Norwegian grandparents, graduated from the University of Wisconsin-River Falls and earned a law degree from UW-Madison.

He is survived by his wife and three sons. Funeral arrangements were pending.