The Leanin’ Tree Museum and Sculpture Garden will close its doors in August, after a more than 40-year presence at the company’s Gunbarrel facility.

The museum features the private art collection — nearly all of it Western- and Native American-themed — of Ed Trumble, the owner of the Leanin’ Tree Greeting Cards company.

Most of the collection will be placed on auction in Scottsdale, Ariz., early next year, according to a news release Wednesday.

“He’s 92, and he decided that everything will be sold with him here or not here,” gift shop manager Danielle Vorthmann said. “He’s excited to see how his collection will do and who will be interested in it.”

Trumble was not immediately available for comment on Wednesday, but Vorthmann said the collection includes more than 300 paintings and about 200 bronze sculptures by artists of varying note.

She said that at least one painting in the museum, by artist Fritz Scholder, was on loan to the Denver Art Museum recently.

Vorthmann said that Trumble has collected art for decades but the museum dates to 1974, when he bought land in what was then farmland in Gunbarrel to build a facility that houses the company’s manufacturing operation.

Outside the building are multiple large metal sculptures that Vorthmann said will have to be sold before they can be moved.

“They had to use cranes to bring them in,” she said.

Leanin’ Tree was founded in 1949 and briefly operated in Fort Collins before Trumble moved it to Boulder. The company works with 600 independent artists to produce more than 30 million greeting cards a year, as well as other items.

The closure of the museum won’t impact the greeting card company, which employees about 200 people, and the company plans to use the space for its factory, Vorthmann said.

She said the museum sees about 25,000 visitors a year.

“We are sad to see the museum go,” she said. “But we want to respect his wishes.”

More information can be found at leanintreemuseum.com. The museum and greeting-card factory are located at 6055 Longbow Drive in Gunbarrel.