Theodore Roosevelt gets rightful credit as one of the tall trees in the nation’s early conservation landscape, but as presidential biographer and historian Douglas Brinkley’s new book tells it, the environmental accomplishments of his fifth cousin, Franklin Delano Roosevelt, cast their own, equally impressive and very long shadow.

Although FDR is best known for progressive New Deal economic and social recovery programs and leading the nation through World War II, Mr. Brinkley’s exhaustively researched book recasts America’s 32nd president as a prime preserver and protector of America’s pristine public lands, and a leader of early efforts to clean up urban blight and industrial pollution.

Mr. Brinkley, 55, will talk about the Roosevelts and his book, “Rightful Heritage: Franklin D. Roosevelt and the Land of America,” at 7:30 p.m. Monday in the Carnegie Music Hall in Oakland. The appearance is part of the Pittsburgh Arts & Lectures’ Ten Evenings series.

The FDR book, published earlier this year, is a companion piece to his 2009 biography, “The Wilderness Warrior: Theodore Roosevelt and the Crusade for America.”

“TR was my boyhood hero, but FDR, after Abraham Lincoln, was our nation’s greatest president,” Mr. Brinkley said, speaking by phone from his home in Austin, Texas, earlier this month. “His environmental legacy was misunderstood and undersung. He came up with the New Deal and the Civilian Conservation Corps. He oversaw the planting of 3 billion trees. He preserved public lands and created America the beautiful.”

In an unavoidably ironic wood resource-consuming 589 pages (744 counting appendixes, acknowledgements, maps, notes and index), Mr. Brinkley details how FDR came by his environmental ethics early and honestly as a boy growing up birding, hunting, fishing and boating in the Hudson River Valley of upstate New York. There, as caretaker of the family’s Hyde Park home he displayed a passion for forestry.

Although he was president of the United States from 1933 to 1945, Mr. Brinkley said, “He liked to introduce himself as a ‘tree grower,’ and he wasn’t being cute.”

The book recounts how FDR’s passion for the outdoors permeated his presidency and made conservation, along with land and water restoration, a priority for a number of the administration’s programs, including the Civilian Conservation Corps. During the nine years the CCC operated it employed almost 3 million men to build trails, dams, roads and bridges in the nation’s parks and forests, clean up polluted landscapes and plant trees to anchor soil and provide wind breaks to combat Dust Bowl soil erosion.

“Everyone focuses on the stock market crash and the Great Depression, but we had blighted landscapes then, too,” Mr. Brinkley said. “FDR began to clean the nation’s rivers, restocked the lakes and streams, brought back deer and ducks and geese whose populations were decimated by overhunting.”

FDR also oversaw a robust expansion of national wildlife refuges and the National Park System, including The Great Smokies, Joshua Tree, the Everglades, Big Bend and the Olympics. Further burnishing his environmental bona fides, FDR spent three weeks while he was president in 1938 in the Galapagos Islands “following in the footsteps of Darwin,” Mr. Brinkley said. And he held press conferences in the Great Smokies and delivered a radio address from Glacier National Park in Montana.

“FDR was part of the forward march of conservation that featured Teddy Roosevelt and Gifford Pinchot [a Pennsylvania governor and first head of the U.S. Forest Service] and that moved on with FDR and Aldo Leopold,” Mr. Brinkley said. “By the Kennedy years, Rachel Carson [a native of Springdale] published “Silent Spring” and started connecting the environment to public health in a much more profound way.

“It wasn’t just about the land then, it was also about health and today, environmental justice.”

Mr. Brinkley, a writer for Vanity Fair magazine, presidential historian for CNN and a professor of history at Rice University, has Pittsburgh-area roots: His father was born in Clarion, and both his father and mother attended Clarion University. His sister was born in Oil City, and he said he has cousins “all over Pittsburgh and its suburbs.”

He’s visited the city before and notes that Pittsburgh is among a group of cities benefiting from their environmental stewardship.

“The key thing is to reclaim riverfronts,” he said, “and Pittsburgh was smart that way.”

He said he hasn’t determined the subject of his next book biography.

“I wouldn’t mind doing President Obama,” he said. “But I think I’ll pass on Donald Trump and Hillary Clinton.”

Don Hopey: dhopey@post-gazette.com, 412-263-1983, or on Twitter @donhopey.

First Published: November 20, 2016, 5:00 a.m.