Patrick McDonough’s art is not infrequently called playful. The Washington artist’s 2010 installation at Flashpoint Gallery, “reck room,” included a foosball/table tennis hybrid that was designed to be used by gallery visitors (and, in fact, was used, by downtown lawyers on their lunch break). His current show at the American University Museum, “bright­veridiansentinelevents” features a punningly titled sculpture, “133006-mussels two ways (muscles two ways).” It’s made from exercise equipment and discarded mussel shells from the D.C. restaurant Marvin.

Yet even he acknowledges that this lighthearted description may not be the best one for his work, which is often as earnest — not to mention as enigmatic — as it is cheeky. “I admittedly ask a lot of people,” says McDonough, whose art, while visually provocative, is also at times perplexing, inviting viewers to puzzle out more hidden connections than they may be used to.

In addition to work evoking mussels/muscles, the A.U. show includes: a sculpture made from Hemcrete (a concretelike building material made from hemp); found photographs of activist Ralph Nader, naturalist John Muir and environmentalist Aldo Leopold; video of the artist tossing golf balls made from cast aloe vera gel at a metal gong; a high-tech sculpture that uses photocatalytic paint to remove nitrogen oxide from the air; and detritus from two recent art actions in which McDonough painted a series of lawns in Rosslyn white.

Are you still with him? “I probably lose some people along the way,” McDonough says of the somewhat arduous conceptual path that his work invites viewers to walk.

Don’t worry. The artist has planted clues along the way to tie all this together. I’m going to help you find some of them.

The first clue is in the title. “Veridian,” a homophone for “viridian” (or green), is the unifying concept, which has to do with sustainability and the environment. That’s underscored in the museum’s outdoor sculpture garden, where you’ll find an array of such drought-tolerant plants as salvia and fescue, growing in cast-off containers that have been turned into planters. (Hemp is also drought-tolerant.)

Why the deliberate misspelling of viridian? “Ver,” which evokes the root of the Latin word for truth, is one likely reason. Again and again, the show hints at the idea of falsehood, as in the case of one sculpture that features a bank of tanning-booth light bulbs. There’s also a kind of television studio set featuring a green screen of the kind used by weathermen to create fake video backdrops.

How did we get onto the weather? We never really left. Remember those drought-tolerant plants? McDonough wants viewers to think about global warming. His white-painted grass is a simulacrum of snow, of which the artist (who’s from Wisconsin) is afraid we might start seeing less and less.

As for “sentinel events,” that connects back to the mussels (there are lots of them in the show): Due to their sensitivity to pollutants, biologists consider the shellfish a “sentinel” species for its ability to warn of environmental degradation. The allusion to muscles suggests that any solution to the problem of climate change is going to involve heavy lifting. And that any faith in a quick fix is a delusion. Which takes us back to the idea of truth.

Okay, okay. So McDonough is waving his hands like a maniac, warning of the dangers of climate change and climate-change denial.

Well, not exactly.

If “brightveridiansentinelevents” is a cautionary tale, it’s an oblique one. McDonough’s work is subtle and complex. He’s also, for example, interested in aesthetics. Although his sculptures can be ugly, as in the case of the Hemcrete lumps, the artist wants us to question what we find beautiful, and why. Although some people find solar panels and wind turbines to be eyesores, those judgments, McDonough argues, are learned behaviors. And they can be unlearned.

None of this, of course, hits you over the head while you’re walking through the show.

Rather, it is questions we’re left with at the far end of “brightveridiansentinel­events,” not answers. That makes for the kind of art that’s troubling, in the best sense of the word.

The Story Behind the Work

Be sure to visit the sculpture garden before you leave “brightveridiansentinelevents.” There, green-minded gardeners will find not only ideas for plants that don’t require a lot of watering, but also a pair of artworks that actually air-condition the great outdoors.

One features an electric air filter, with a motor powered by a solar panel. It briefly comes on automatically, every 20 minutes or so. The other pieces work more quietly, using panels that have been coated with special paint that bonds with noxious chemicals. When activated by sunlight, those atmospheric pollutants are broken down into harmless organic compounds, including water and carbon dioxide.

If it sounds like a sermon or an industrial demo, Patrick McDonough denies that he is either a preacher or a salesman. He fully realizes the futility of trying to scrub the Earth of smog through paint. His piece may be green, at least figuratively, but in the end, McDonough says, it’s also “just a painting.”

— Michael O'Sullivan