In comparison to very tall trees, the San Francisco artist Kal Spelletich suggests, people are losers. "Cosmicism and Contemporary Forestry from Northern California," Spelletich’s summer exhibition at Jack Hanley Gallery, includes several sepia photo collages of giant Sequoias, Redwoods, Monterey Pines and palm trees. Snapshots of sections of their sometimes 100-foot-high trunks are lined up vertically, as if they cannot be contained in one photograph. Antique coloring also refers to their great age, and as they narrow away to the sky, they seem to be fading away into the past.

Providing a contrast to these fragile photographic illusions are three charmingly absurd yet somewhat sadistic Rube Goldberg-esque mechanized contraptions made of sections of salvaged wood, ornamented with lichens and pinecones, and connected by metal joints and rivets. (Spelletich is a member of a collective devoted to robots and extreme machines, and has worked with the legendary Survival Research Laboratories.) The largest sculpture in the show, Robotic Tree, Point Lobos: Monterey Pine (2010) stretches across the center of the gallery, held up by some small metal beams. Turned on, it wiggles almost helplessly a bit from side to side, as if it were trying to swim.

Resting on a pedestal, a smaller battery-powered machine -- a coffee-table version of the big one on the floor -- can be sent into awkward undulations by pressing a silver button. And attached to the wall, the series of branches in BB-Q (2010) culminate in a small gas burner. With a red power switch, a small engine and some black tubing (that presumably attaches to a gas source), it is set up to cook frankfurters impaled on the spits of a multi-spiked circle that is rotated by tiny gears. Passing through the flame one by one, the hot dogs are like tiny damned bodies suffering in a miniature hell.

Reducing relics of majestic trees to abjectly useless machines, Spelletich creates a rather poignant allegory for pitiful human attempts to live in harmony with nature. Chopped into fragments, pierced with metal and forced to move in unnatural ways, these sorry remnants of once stately arbors bring petrified worms to mind. Outlining a benevolent scenario for his exhibition, Spelletich expresses a desire to "feed the masses" with his little barbecue machine, but I don’t believe a word of it. He wants to tantalize the viewer with fragmented sepia memories of trees we’ll never see, all the while torturing their corpses. A four-part photo collage is $500, while the largest machine can be yours for $5,000.

Kal Spelletich, "Cosmicism and Contemporary Forestry from Northern California," Aug. 5-31, 2010, at Jack Hanley Gallery, 136 Watts Street, New York, N.Y. 10013

ELISABETH KLEY is a New York artist and writer.