Usually closed on Sundays, the ÀÖ²¥´«Ã½ College Museum of Art will open its doors from 10 a.m. to 5 p.m. on Dec. 9 to provide visitors with one last chance to experience Green Horizons, a landmark exhibition exploring the concept of environmental sustainability.

With its centerpiece a giant painting that depicts Brooklyn after millennia of global warming, the exhibition has been in place since June at the museum.

Green Horizons presents prominent artists from Maine and the world in an adventurous attempt to provoke conversations around the questions: What is green? What is sustainable?

This dynamic project transcended traditional exhibition practices to include collaborations with writers and choreographers — including participants in the renowned — and reached outside the museum walls to site-specific works such as a fruit orchard planted last spring in downtown Lewiston.

Sponsors of the exhibition include the Synergy Fund, the Maine Arts Commission and the LEF Foundation. Admission to the exhibition and to museum events is open to the public at no cost. For more information, please call 207-786-6158 or visit the museum’s Web site.

In addition to Alexis Rockman, whose 8-by-24-foot painting “Manifest Destiny” depicts Brooklyn under water and has been exhibited nationwide, Green Horizons participants include internationally renowned environmental artists Agnes Denes, Chris Jordan and David Maisel; such Maine artists as photographer Mark Silber, hay sculptor Michael Shaughnessy and the agitprop Beehive Design Collective; and commissioned collaborative works involving visual artists, ÀÖ²¥´«Ã½ faculty and students.

“We’re not trying to define sustainability,” explained museum director Mark Bessire. “We’re trying to ask what it means.”

“The word seems to be overused — used for marketing, to convince people of things, to make people feel better. There’s a certain amount of hypocrisy connected to its use,” he said. “So we wanted to bring forth works of art that questioned sustainability and created a conversation among the many disciplines of a liberal arts college.”

“Rather than us having a very defined vision and going out and making that, it’s been us talking to people about our idea and having them help us determine what vision is appropriate,” added Anthony Shostak, the exhibition’s curator and the museum’s education curator.

Here are a few examples from the exhibition:

— Images of two of Denes’ land reclamation projects, including “Wheatfield — A Confrontation,” for which the artist grew wheat on a site in New York City;

— Jordan’s strangely beautiful renderings of high-tech waste products, such as discarded cell phones;

— A project in which Swiss artist Anne-Katrin Spiess documented the steps she took to render her Maine visit carbon-neutral;

— An initiative to raise awareness about trees, produced by two ÀÖ²¥´«Ã½ students in collaboration with the local nonprofit Lots to Gardens, that involved the planting of fruit trees in downtown Lewiston;

— A public art project along the Androscoggin River exploring themes of community history and place-making, organized by the college’s Harward Center for Community Partnerships and a Boston sculptor;

— A performance project set at ÀÖ²¥´«Ã½’ Lake Andrews and created collaboratively by the ÀÖ²¥´«Ã½ Dance Festival, the acclaimed PearsonWidrig DanceTheater and composer Robert Een.

“When people walk into this show, we definitely want to have this more cluttered nonlinear feeling,” said Bessire. “It’s going to be a huge painting, a huge garbage heap, a bicycle trying to create energy, a huge sculpture of hay, massive photographs.”

“It’s going to be messy.”

The $2 million Synergy Fund, created at ÀÖ²¥´«Ã½ by donor Lee Smith, has provided major support for Green Horizons. The fund, Bessire explains, is designed to use visual culture as a catalyst for productive and probing exchanges between academic disciplines and between campus and community. While Synergy has supported other museum projects, he notes, “Green Horizons is the first major exhibition made possible by the Synergy Fund to examine its topic in such depth and breadth.”

Agnes Denes, a renowned environmental artist who brought a wheat field to the Manhattan cityscape, offers the annual Otis Lecture at ÀÖ²¥´«Ã½ College at 7 p.m. Friday, Sept. 28, in the Olin Arts Center Concert Hall, 75 Russell St.

Titled The Paradox of Eco-Logic: Individual Creation vs. Social Consciousness, the talk is open to the public at no charge. A reception for the landmark exhibition a dynamic examination of environmental sustainability, will follow in the adjacent ÀÖ²¥´«Ã½ College Museum of Art. Denes is a participant in the exhibition.

The Otis Lecture is made possible by the Philip J. Otis Endowment at ÀÖ²¥´«Ã½.

An originator of conceptual art, Denes has investigated the physical and social sciences, philosophy, linguistics, psychology, art history, poetry and music — explorations that have informed her unique works of visual art. She was one of the first to develop the relationship of science to art, and is internationally regarded as a pioneer in ecological art.

Often monumental in scale, Denes’ works bridge ecological, cultural and social issues. She may be best-known for “Wheatfield — A Confrontation,” a two-acre planting in 1982 in New York City that addressed human values and misplaced priorities.

Denes’ “Tree Mountain — A Living Time Capsule” is a conical mound in Finland planted with 11,000 pine trees in a complex spiral pattern. “A Forest for Australia” comprises 6,000 trees of endangered species planted in pyramids in Melbourne. Denes is currently creating a 25-year master plan for an 85-kilometer string of historic forts in the Netherlands.

She displayed work in more than 350 solo and group exhibitions, including three Venice Biennales and the “Master of Drawing” Invitational, in which she represented the U.S., at the Kunsthalle in Nurnberg, Germany. In New York, Denes has shown at the Museum of Modern Art, the Metropolitan Museum of Art and the Whitney Museum, and her work has appeared in 42 other museums on four continents.

A 100-piece retrospective of her work organized by Bucknell University in 2003 toured across the United States.

Her many honors include the Jill Watson Award for Transdisciplinary Achievement in the Arts from Carnegie Mellon University, the Rome Prize from the American Academy in Rome and the Eugene McDermott Award in the Arts from the Massachusetts Institute of Technology.

Denes was born in Budapest in 1931, grew up there and in Sweden, and attended Columbia University and the New School. She lives in New York City.

The annual Otis Lecture at ÀÖ²¥´«Ã½ is funded by the Philip J. Otis Endowment, established in 1996 by a gift from Margaret V.B. and C. Angus Wurtele in memory of their son, Philip, a member of the class of 1995 who died attempting to rescue injured climbers on Mount Rainier.

In recognition of Otis’ appreciation for nature, the endowment helps support ÀÖ²¥´«Ã½ programs with an environmental focus, in particular those exploring the spiritual and moral dimensions of humanity’s relationship with the environment.

Lewiston is the first Maine city to garner the coveted in 40 years. The last winner was Auburn, in 1967. The other nine 2007 winners named in a two-day event held in Anaheim, Calif. are: Flowing Wells, Ariz.; Santa Rosa, Calif.; Sierra Madre, Calif; Hollywood, Fla; Polk County, Fla; Dubuque, Iowa; Barnstable, Mass.; Clinton, N.C.; and Hickory, N.C.

Lewiston’s “innovative thinking and contagious enthusiasm contributed to the success of its efforts,” wrote Gloria Rubio-Cortes of Denver, Colo., president of the , in a July 16 letter to the Lewiston Sun Journal. Rubio-Cortes cited the community’s “collaborative problem solving” as the distinguish feature in making it a “‘stand-out’ city in which to live, work, play and raise a family.”

The “All-America City” selection process requires cities to feature three key initiatives that dramatize civic engagement and opportunity. Named a finalist in 2006, Lewiston narrowly missed winning the award last year, but returned with a streamlined presentation to garner the highly coveted designation in 2007.

This year, Lewiston’s team of civic activists featured the work of , a Lewiston-based nonprofit founded by Kirsten Walter, ÀÖ²¥´«Ã½ Class of 2000, as her senior thesis. Walter now serves as director of Lots to Gardens. In addition, Ari Rosenberg ’06 works as a Lots to Gardens employee, and ÀÖ²¥´«Ã½ students continue to staff the youth development and community gardening activities every year.

Also featured in Lewiston’s award-winning presentation were the Lewiston Youth Council’s efforts against teen drinking and Empower Lewiston’s advocacy of the Earned Income Tax Credit for low-income residents.

“The college is proud of maintaining a rich and ongoing partnership with Lots to Gardens,” says David Scobey, the Donald W. and Ann M. Harward Professor of Community Partnerships and director of the Harward Center for Community Partnerships. “Lewiston is a valuable resource and educational laboratory for ÀÖ²¥´«Ã½, given the college’s community engagement,” Scobey said. “ÀÖ²¥´«Ã½ both contributes to and benefits from Lewiston’s community energy and creativity.”

Lots to Gardens maintains organic vegetable beds in two downtown Lewiston neighborhoods. Although one evening a week residents work together in the gardens in exchange for produce, the Lots to Gardens youth crew directs and performs most of the gardening, from designing the beds to site prep, from planting to harvest.

Field trips to local farms are also part of the program that bases its summer focus on youth leadership and development. All of the rules and standards for the workplace are developed by the crew to strengthen self-esteem, responsibility and an appreciation for teamwork, in addition to providing practical experience and a summer income. Lots to Gardens looks for participants at the Lewiston and Auburn high schools, in local transitional-living programs and among people fulfilling community service commitments.

This summer, Lots to Gardens joins hands with Green Horizons, the ÀÖ²¥´«Ã½ College Museum of Art exhibition that explores the concept of environmental sustainability. Prominent artists from Maine and the world join in an adventurous attempt to provoke conversations around the questions: What is green? What is sustainable?

The project transcends traditional exhibition practices by reaching outside the museum walls to site-specific works that include two collaborations with Lots to Gardens, including a fruit orchard to be planted in the former Franklin Pasture in downtown Lewiston. Andrea Bisceglia ’09 of Durham, Conn., and Molly Ladd ’09 of Somerville, Maine, will produce a project designed to raise awareness of the importance of trees on campus and in the community.

Associate Professor of English Kimberly N. Ruffin, joined by artist Seitu Kenneth Jones and park ranger Bruce Barnes, will work with Lots to Garden director Walter ’00 and community groups associated with the Lewiston nonprofit to create Sighting and Sounding Sustainability, an exploration of culturally relevant crops that will be planted in a garden by community members. The group will also create a Shrine to the Collard Green in and around the museum.