Kurt Steger is interested in time, in the way it transforms both natural and man-made elements, in the way it changes things in the visible world, in the way we are changed by it. It is the key element in many of his new sculptures at Julie Baker Fine Art in Grass Valley.

A woodworker and fine furniture maker turned sculptor, Steger gives us several pieces that will change with the passing of months and years. Meant to be placed outdoors, they will weather and acquire patinas. Some may even collapse and disintegrate, teaching us, as if we needed to be taught again, that all things are ephemeral, that all things change and ultimately pass away.

Titled "Weight of Time," the show, Steger states, "reflects the uncertainty and weightiness of the world events we are facing." But it does so not in any simple or obvious way. Steger's finely crafted works hark to the realm of metaphor, giving us complex images that speak to themes of loss and impermanence, fear and uncertainty, journey and transformation.

At the heart of the show is an installation whose centerpiece is the powerful sculpture that gives the show its title. "Weight of Time" plays heavy and delicate materials against each other in a work that, despite its mass, is graceful and elegant. Hanging by thin steel wires from a curving convex wooden beam that suggests the lintel of a Japanese tori gate, a chunk of concrete with rock tailings from the nearby Empire Mines is suspended over a wooden trough of water, suggesting that the piece is a kind of bridge, carrying heavy freight.

We feel the weight of the suspended form and the uncertainty of the thin wires that hold it even as we sense the transformational nature of its journey over healing water. The whole is set in gray sand raked in concentric lines that echo the footprint of the sculpture, an evanescent Zen garden, and the piece is flanked by a pair of drawings done directly on the gallery's walls.

The drawings take the form of sunlike circular spots made up of intersecting lines. On the left, a network of random charcoal crosshatches, bristling with dark energy, forms "Death After Life." On the right, "Life After Death" is a welter of similar markings in brilliant white chalk against a dark background. Presented as aspects of the same phenomenon when looked at differently, they speak of disruption and continuity as opposite sides of the same coin.

Meant to be placed outdoors, "Weight of Time" will change as nature and the elements work on it, as will "Adrift," an arklike vessel that encloses a canoelike trough filled with water. As a vessel that is a refuge for another vessel, it speaks of a double longing for safety and endurance, an emotion common to all of us in these hard times. As the seasons change, creatures may take up residence in the ark, peering out of its crude windows, drinking from its trough of water. The wood will weather and crack. The water may grow moss or algae or leak slowly away. "Adrift" is a rough refuge that seems fragile in the face of time and the changes it will bring.

Weather and nature will also work on an untitled pair of tall sail-like forms that resemble the innards of small airplane wings. The shelflike skeleton of the pieces will act as catchers for snow or falling leaves, making the piece a kind of repository for natural elements.

Steger also addresses the landscape in another pair of outdoor pieces so beautifully crafted that you want to run your hands over them to feel their smooth and rough textures. "Suspended Horizon," made of wood, concrete, water, copper and steel, is an almost decorative piece in which undulating, abstracted hills in earthy reds and browns are suspended over a trough of water. "Titra" is a grittier piece in the form of a rocking half-circle of wood and concrete that is topped by a miniature landscape of black forms echoing the formations of the Sutter Buttes.

Indoor pieces range from "Web," a network of black strings that form a totemic wall piece, and "Shield," a spooky, spiky covering for a torso made of wood and painted paper, to the magnificent "Migration of Souls." Installed against a stark white backdrop held in place with flat river stones, "Migration of Souls" suggests a skeletal boat suspended over a vast abyss. With long, fleshy forms made of wax and human hair hanging above it, it might be a slave boat bearing tortured human cargo. Conversely, its lightness and openness taken in concert with the white expanse below it conjures up a spirit boat transporting souls to an unknown realm.

Steger has previously shown his work at the Sonoma Museum of Visual Art in Santa Rosa and at Exploding Head and b. sakata garo in Sacramento. He made a strong impression in those local showings, as well as in the last Crocker-Kingsley Exhibition, but this is his most coherent and powerful show to date.