PORTLAND — Edward Weston, one of America’s most innovative and influential photographers, traveled cross country to capture America’s culture and spirit of the 1940s.

His goal was not to photograph the nation’s untouched beauty.

Rather, at the request of the Limited Editions Club of New York, he set out in early 1941 to take photographs to illustrate its deluxe edition of Walt Whitman’s epic poem, “Leaves of Grass.”

Originally published in 1855, “Leaves of Grass” has since appeared in many editions. The first volume contained 12 poems, but by the time of Whitman’s death in 1892, it had grown to more than 400 lyric poems focusing on everyday life in America — people in small towns as well as views of industrialized metropolitan areas, landscapes and architecture.

Weston did not photograph specific locations mentioned in this work by one of America’s greatest poets. He wanted to be “absolutely free to do anything he wanted to do from a cloud to an old shoe,” as he stated in the introduction of “Leaves of Grass,” in the 1942 edition.

Fifty-three of Weston’s wide-ranging, black-and-white images — taken while traveling through 24 states, covering 25,000 miles in almost 10 months — are on view at the Portland Museum of Art through March 13.

Weston’s photographs are clear, detached visual documents of the times, rather than the exciting sensual beauty we see in his photographs of vegetables and the human body.

“Over the course of the project,” according to the PMA, “Weston managed to produce some of the most compelling images of his later career that took his photography in a new and important direction.”

For his “Leaves of Grass” trip, Weston, who traveled with his wife, Charis Wilson, used a large 8- by 10-inch camera. He developed almost 700 images and sent in 74.

The PMA exhibit begins with photographs of California and ends with images of the East Coast, including two taken in Maine — one of the Wedding Cake House and the other of a schooner docked in the harbor.

Some memorable photos in the second-floor exhibit are “Tree, Near Nashville Tennessee,” “Mr. and Mrs. W.P. Fry, Burnet, Texas,” “Grand Canyon, Arizona,” “Greenwich Village,” “Shenandoah Valley, Virginia” and “William Edmondson, Sculptor, Tennessee.”

A favorite work of this reviewer is “Tree, Near Nashville Tennessee,” because of its mystical quality, symmetrical balance of composition, use of negative space and sparse forms.

The “Leaves of Grass” exhibit, organized by the Boston Museum of Fine Arts, is thought-provoking. It is an important reflection of our nation, both historically and aesthetically.

Various editions of the “Leaves of Grass” book are available to browse through on a library table with old-fashioned library lights in one of the galleries.

The museum at Seven Congress Square is open 10 a.m. to 5 p.m. Tuesday, Wednesday, Thursday, Saturday and Sunday; and 10 a.m. to 9 p.m. Friday. Admission is $10 for adults, $8 for seniors and students with ID, $4 for youths ages 6-17 and free for children under 6. Admission is free from 5 to 9 p.m. Friday.

Pat Davidson Reef has a master’s degree in education and has taught art history at Catherine McAuley High School in Portland. She has written two children’s books, “Dahlov Ipcar, Artist,” and “Bernard Langlais, Sculptor.”