Bruce Conkle has been in all kinds of group shows around town, and solo shows as far away as New York City and Iceland, but this is his first local solo show since 2004. As Portland's preeminent "eco-artist" (whatever that means), Conkle is perennially fascinated by the environment in general and global warming in particular, and his current show at Rocksbox, Friendlier Fire, updates these pet themes with deep foreboding.

When you walk into a Bruce Conkle show, you enter a sylvan fiefdom with a different set of aesthetic parameters. In essence, the work is high concept but low budget. Past shows have been fashioned from aluminum foil and stuffed animals; this one is mostly comprised of scrawly, amateur-chic drawings, Styrofoam coffee cups and black-lit incense burners. It's all part of the artist's populist strategy to make fine art more accessible to the archetypal "common man." As Conkle told me on opening night, "When people say, 'My 5-year-old could've made that,' I take it as a compliment."

Conkle imagines the world as a better place after the environmental apocalypse he is convinced is looming. In his drawings, his melting snowmen—a favorite canary-in-the-coal-mine motif for global warming—have liquefied and watered the roots of trees, reincarnating themselves as pagan tree spirits. His A New Beginning rings a nuclear mushroom cloud in a cheery rainbow, suggesting a beatifically human-free planet after the jump. The Cup Room leads the viewer through a forest of used Starbucks cups stacked one atop the other in a memorial to post-consumer waste. And the show's most imaginative departure, TGI Doomsday, portrays the White House fireplace as it might appear after environmental Armageddon: lit by a sorry propane canister, the flame's lonely shadow flickering over an overhead-projected drawing.

Conkle has created an artistic jurisdiction in which normal expectations of sophistication in craft and materials do not apply; in which, as the price of entry, you must give yourself over to a vision of nature that is as childlike and romantic as its view of technology is jaundiced. Despite its rainbows, this is a show of dark poetry.

Friendly Fire

at Rocksbox, 6540 N Interstate Ave., 971-506-8938. Closes Oct. 26.