John C. Stokes, 70, of Haddonfield, a former planner and executive who played a leading role in the preservation of the 938,000-acre Pinelands in South Jersey, died Tuesday, July 14, of an aneurysm at Cooper University Hospital in Camden.

Mr. Stokes was executive director of the New Jersey Pinelands Commission from April 2003 until his retirement in early 2011. He took the top post after serving for 23 years as assistant director.

An original member of the commission’s staff, he was one of the chief authors of the Pinelands Comprehensive Management Plan, the rules that govern land use, development, and natural resource protection of the tract. Under his guidance, the plan was updated with 15 amendments.

“John’s service to New Jersey as executive director of the Pinelands Commission was invaluable,” said former New Jersey Gov. James J. Florio, who chaired the commission from 2002 to 2005.

“When I served as chairman of the Pinelands Commission, I observed his practical, wise, and environmentally sensitive work in action. His approach was key to protecting and preserving a fragile part of New Jersey that constitutes 20% of the state. New Jersey has lost one of its most valuable citizens,” Florio said.

“John Stokes was a giant in the protection of the New Jersey Pinelands,” said Betty Wilson, who succeeded Florio as commission chair from 2005 to 2008. “He dedicated his professional life to the preservation of the Pinelands National Reserve.

“All who knew and worked with John felt his deep personal and professional commitment to the preservation of the Pinelands. The Pinelands National Reserve stands as a monument to John’s dedication, his intelligence, and his steady hand of leadership.”

The commission, an independent state agency, is governed by a 15-member panel appointed by the governor, the seven counties the reserve spans, and the U.S. secretary of the interior. Parts of the Pinelands are in Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, and Ocean Counties.

As executive director, Mr. Stokes oversaw the commission’s daily operations and its staff of 43 planners, scientists, environmental reviewers, and educators.

Under his tenure, the commission set up a conservation fund to permanently preserve nearly 9,000 acres in the Pinelands, instituted measures to protect 7,000 acres in Ocean County ‘s Toms River and Oyster Creek Basins, and launched a study of the Kirkwood-Cohansey Aquifer beneath the reserve.

“I personally think there are few people that have done more to advance the cause of Pinelands preservation than John Stokes, both from his early days as a staff member to his leadership as executive director,” said Alan W. Avery Jr., the commission’s current vice chairman.

Terrence Moore, the commission’s executive director from its inception in 1979 until 1999, said Mr. Stokes’ methods for developing the comprehensive plan and implementing it have become a national model.

“To those who worked closely with him in this endeavor, as I did for its first 20 years, he has remained a close and cherished friend and will be greatly missed,” Moore said. In retirement, the two met for lunch, Mr. Stokes’ family said.

Born in Philadelphia, he grew up in Haddonfield. He graduated from Haddonfield Memorial High School in 1968 and earned a bachelor of science degree from North Carolina State University in 1972.

He was certified as a New Jersey professional planner and was a member of the American Institute of Certified Planners.

A civic volunteer, Mr. Stokes was chairman of the Haddonfield Planning Board, a member of the Haddonfield Environmental Commission, treasurer of the Camden County Council of Girl Scouts, assistant administrator of the National Little League in Haddonfield, and a member of the Haddon Avenue Transit Corridor Study Committee.

After retiring in 2011, Mr. Stokes taught master’s level courses in environmental science at Stockton University. He enjoyed working in his yard and participating in activities with the Haddonfield Lions.

He is survived by his wife of 51 years, Linda Baud Stokes; a son, Daniel; a daughter, Wendy Donaway; three grandchildren; and a brother.

A viewing was held Monday, July 20. Services and burial were private.

Donations may be made to the Haddonfield Lions Foundation, Box 401, Haddonfield, N.J. 08033.