AT the Corcoran Gallery, "Spectrum: Natural Settings" shows 15 attempts to fool with Mother Nature. These are landscapes Frederic Church never dreamed of.

Cheryl Laemmle, one of the seven artists whose work is displayed here, expresses the prosaic idea of evergreens on a snowy hillside through an unusual device. She arranged 77 cutout trees on a wall painted gallery-white. One might still dismiss it all as a Christmas card gone wild, were it not for the fact that the trees nearer the ceiling diminish in size, giving the optical effect of a slope. And, from a single tiny cabin nestled under one of the trees, two windows gaze on the viewer and invite speculation on scale and human insignificance.

Idealized landscape artists like Church form a point of departure for April Gornik, whose "Suspension" explores the indifference of nature. In this luminous painting, brown-black clouds edged in sunset orange are swallowing a blue sky; a featureless sea reflects the scene. Clouds and rocks form a stasis that will be rent by the inevitable storm.

The disembodied ceramic heads of Michael Lucero are based on the idea of the head of a Roman statue broken off and lying in ruins. Wildflowers and weeds would grow up around it -- but Lucero's natural world grows into it. "Island Dreamer" gives the illusion of a head dripping and flowing, as hair melds with stream. Lucero asks us to wonder where imagination begins.

Jim Sanborn's awe at the unnatural world is expressed in a dramatic sculpture, "Striking Stones Under the Thunder." A "thunderhead" parts to let a lightning bolt through. The artist produces the effect of lightning by directing light through a crack in a slate roof, the roof being the thunderhead itself. Seeking a lodestone, the lightning streaks between two pillars of stacked sandstone that stand for eons.

This show is the first of three parts in the Corcoran's "Spectrum" series, exploring contemporary art issues.