Meredith Monk’s works are like rites: relics of a lost culture you once knew about, emerging from some untapped collective unconsciousness in the corners of your own mind. The performers chant, their voices weaving in complex maypole patterns, or move their hands in quick sharp planes like folded paper, or rock back and forth and make quiet sounds like keening — or any of dozens of other ways to use the voice.

People don’t always know what to call this work — Monk was long labeled a “choreographer,” is now more often called a “composer” and is maybe best described with the amorphous “genius” tag that accompanies receipt of the MacArthur Foundation award she got in 1995. And people don’t always know what to make of the work, either. Some people find it utterly simplistic; others become adoring fans. Few remain ambivalent.

Monk is not bothered. She simply continues to make pieces that may or may not include music, movement, projections, video, narrative, you name it, taking one step after another, extending herself gradually in different directions. In recent years — she’s 71 — this has led to some of the best and richest work of her career: “Songs of Ascension,” in which vocalists and string quartet sing and play and move along two intertwining spiral staircases in a tall tower (a rite, indeed), or “Impermanence” (2005), a reaction to the sudden death of her longtime partner, Mieke van Hoek, in 2002. Her latest multi­­media theater work (for lack of a better term) is “On Behalf of Nature,” which is about nature and the environment — a self-described attempt at an “ecological art work” — and which is coming to the Clarice Smith Performing Arts Center at the University of Maryland on Saturday night. After its premiere in January at UCLA, Los Angeles Times critic Mark Swed called it “some of the finest music Monk has yet written.”

“I’m basically devoting the rest of my life to pieces [about subjects] that you can’t make pieces about,” Monk joked, speaking by phone last week from her home in New York. “How do you make a piece about something so literal? Everything you do could turn into this literal silly message.”

It’s hard to pin down in what sense a Monk piece is “about” anything. But certainly some of her previous pieces have included clear vignettes, such as “Magic Frequencies,” a “science fiction opera” that opened with aliens observing the rituals of ordinary Earthlings at dinner. And “On Behalf of Nature,” her ecological opera, couldn’t do anything so clear-cut. Its most literal reflection of its theme: recycling. Monk used a couple of movements from past works (including “Realm Variations,” which she wrote last year for the San Francisco Symphony), sketches from old composing notebooks and bits of video from her 1988 film “Book of Days,” although cut up and reassembled in a wholly new form. In this repurposing, she was following the lead of the piece’s costume designer, Yoshio Yabara, who rather than create new outfits from scratch, used the performer’s own clothing, tearing it up and making it into entirely new garments.

Meredith Monk (Jesse Frohman)

But “I wasn’t going to do nature films or films about coal mines,” she says of the accompanying video. “Any kind of image became so completely corny and stupid.”

The resulting piece is an abstraction — it’s more a meditation than a narrative,” she says. “I think of it more as an offering.” She adds: “It’s kind of a ritual to acknowledge these energies that go unrecognized, to somehow make people aware of what we’re in danger of losing” — that is, the beauties of the natural world — “but without pointing a finger. I can’t work that way. Will you get enough what the piece is ‘about,’ because it’s so abstract — but that’s much more honest for me. I don’t know how to do that playwriting kind of thing. We have plenty of finger-pointing as it is.”

Monk has managed to remain sui generis, even as many other artists have come after her whose vocal-
performance-multi­media work might appear at least superficially related: from Joan La Barbara to Laurie Anderson to Pamela Z. Perhaps it’s because there is nothing extreme or self-indulgent about even her most personal pieces: They are always accompanied by an inner rigor. “Each time I make a piece,” she says, “I think of it as a world. Part of my process is digging down and trying to understand what the laws and principles of that world are and what does the piece need.”

Because her music doesn’t follow the Western-art playbook, a lot of people still misunderstand it — even at a time when our ears are far more open to alternatives from around the world. Javanese gamelan and Tuvan throat singing are not unfamiliar elements in concert halls. Monk’s “extended vocal technique” includes a lot of sounds and effects that are not a traditional part of classical vocal tradition: tinny nasal tones, or breathy huffs. But the work is a lot harder than it seems to someone who measures music by the yardstick of Beethoven’s counterpoint.

It’s also harder to commit to paper. Monk composes like a choreographer or a sculptor, tweaking and adjusting the material in front of her. Until recently, her work was an oral tradition, passed on to the members of the ensemble she founded in 1978. But as the artist got older and began thinking about her legacy, she realized that there was going to have to be some way to offer it to posterity. The music publisher Boosey and Hawkes took years to convince her to sign with them; once she did, it was not entirely easy to get the work notated. “Panda Chant,” one of the first published scores, is a minute and a half of music; figuring out how to write it down, Monk says, took 21 / 2 years.

“It isn’t how do you actually get the sound that you’re looking for,” she says. “People are going to play it however they want. But how are you at least clear in conveying the principles of the music. In my music, you always have to understand the principles.”

Yet in her own mind, today, the multi­media aspects of her work are taking second place to the composing. And “On Behalf of Nature,” she says, is “so complete in the music that I would very happily do it as a music concert.”

On Behalf of Nature

will be performed by Meredith Monk & Vocal Ensemble at 8 p.m. Saturday at the Clarice Smith Performing Arts Center. Tickets: $10-$35 from the Clarice Smith Center box office,