A pair of forearms reaches into a royal blue background from the left. In the hands, blazing citrus. A message reads, "ORANGES ON FIRE."

This mysterious and ambiguous 1975 image will appear beginning Nov. 2 on billboards in 20 locations around the Milwaukee area, from South Milwaukee to Slinger, Pewaukee to Franklin, and points between.

What are they?

The signs are a temporary public art installation tied to Milwaukee Art Museum’s new show, "Larry Sultan: Here and Home," the first retrospective of work by the West Coast photographer and artist, who passed away in 2009. The show, which opens this weekend, was organized by Los Angeles County Museum of Art.

The large exhibition, in the Baker/Rowland Galleries in "the Calatrava," comprises a billboard, film, more than 200 photographs and "Study Hall," an iPad-equipped room that allows visitors to dig deeper into Sultan's photographic archives.

"Larry Sultan: Here and Home" captures moments from across Sultan's nearly 40-year career, focusing on six bodies of work, from the conceptual collaborations with Mike Mandel – like the billboards – to his later series of photographs: "Evidence" (1975-77); "Swimmers" (1978-82); "Pictures from Home" (1983-92); "The Valley" (1997-2003); "Homeland" (2006-09); and Sultan's editorial work for newspapers and magazines.

^{Larry Sultan My Mother Posing For Me From the series, "Pictures From Home" 1984 Chromogenic print Image: 40 x 50 in.
(101.6 x 127 cm.) Courtesy the Estate of Larry Sultan © Estate of Larry Sultan}

"Pictures from Home," a series for which Sultan recruited his parents to pose – willingly, but not always completely submissively – is especially engaging, exploring not only the nature of home, but also the nature of the spoken and unspoken relationships among close-knit family.

These photos are revealing and secretive at the same time, but always with a familiar ring to the viewer, who might recognize themselves or people they know in these staged scenes.

"Ambiguity was a really important part of Larry's work," says Lisa Sutcliffe, MAM curator of photography and new media. "He was someone who was interested in creating a narrative through his photographs, (and) this kind of moment of unknown. Not knowing what might be taking place, but there's a tension there."

The billboards Sultan and Mandel created first appeared in California and New York, amusing and confusing viewers, who hopefully got the message about just how pervasive advertising images had become in our lives, something that’s grown even more true in the intervening years.

Both Sultan and Mandel, who met at the San Francisco Art Institute, studied political science, says Sutcliffe.

"Both were battling against the idea of the fine photographic print. There was a romanticism at work at the San Francisco Art Institute, a la Ansel Adams," she says. "Larry and Mike were much more interested in the advertising language that had surrounded them growing up in the San Fernando Valley. They were interested in a more conceptual photography."

In a later artistic statement on the project, Sultan and Mandel wrote, "Beginning in 1973 and up until 1989, we worked together on open ended, allusive designs for outdoor advertising billboards, under the name Clatworthy Colorvues.

"The billboards were exhibited mostly in the San Francisco Bay Area, where we lived, but sometimes installed in other parts of the country, the result of workshops we led with graduate students, or exhibitions on appropriation and public art. With the billboard, we wanted to reach a larger and more varied public than would ever find its way into an art institution."

Sutcliffe says that in their "Evidence" collaboration, Sultan and Mandel's use of images taken by others suggested that, "A. authorship is in question and B. when photographs are taken out of context they can have new meanings. The ideas of photography were changed by this project."

Their billboards – a stunning original lithograph of "Oranges on Fire" is included in the exhibition – can be viewed in a similar spirit.

"They were actually photographing billboards at the time and then decided to collaborate and make their own billboards," says Sutcliffe. "They'd grown up in Los Angeles and they thought of the billboard as a kind of American folk art.

"They were interested in using the language of advertising but not trying to sell you something. So, again a kind of absurdist gesture. Also repeating what is visual, the picture, with nonsensical text. So, of course, they are oranges on fire but that doesn't tell you anything about why the oranges are on fire."

The artists would pose as journalists and ask onlookers what they believed was the significance of the billboards.

"The ambiguity is left sitting in your lap to wrestle with," says Sultan's widow Kelly Sultan – again about "Evidence" – but again quite relevant to the outdoor images.

"There is no clear meaning and that's what created a lot of controversy and conversation about authorship and context and meaning."

Milwaukee Art Museum's returning of the image to billboards once again, this time in connection with the exhibition, further clouds how we view it. Created to use the vernacular of ads but not sell you anything, the blazing citrus is now being used to "sell" the exhibition, but only sort of, since the signs will not carry any text beyond the original three-word phrase.

Ambiguity.

Though the show runs through Jan. 24, the billboards – which were donated to MAM by Clear Channel – will come down after eight weeks, around Dec. 30. Capture photographs of them and post them to social media with the hashtag #hereandhome.

As part of "Here and Home," Milwaukee Art Museum is hosting the MKE Challenge, a series of six-week photography assignments with lessons from Sultan and his proteges. To take part, follow MAM on Facebook, Twitter, or go online. Then you can upload images to the MAM website, or tag the photos on social media with the hashtag #MKEChallenge. Completed assignments will be displayed digitally at the museum.

In related news, the museum’s permanent collection galleries will reopen on Nov. 24. Stay tuned for an updated look inside, coming soon.