SCULPTOR Michael Gessner calls himself a "folk expressionist," and the title is apt. Like many folk--or untrained--artists, Gessner discovers his vigorous fantasy figures within the natural twists and curves of the sticks and branches he collects.

Making them his own by carving sparingly here and there, he often leaves the bark to represent clothing and adds wooden faces, hands or feet.

The energetic results--"Wild Wood Spirits," "Branch Dancers," and "Wild Boys"--pirouette their way around the Fondo Del Sol Visual Art and Media Center in a first solo show of vitality and wit.

A friendly, flexible "Snake"--built of dozens of short sticks bound together--makes his way gracefully across the wall. "Walking" is one of several figures that is pegged so it can be moved into various positions, all graceful and recalling dance. "The All-American Stick Figure" is one of an ongoing series of "business totems" that poke fun at the dressed-for-success businessman.

Some pieces are easy--silly, in fact--especially his women who are nothing but decorative jokes with appropriate appendages attached.

The overall look is updated primitive, with overtones of indigenous African or Oceanic art, no surprise when we discover that Gessner spent some years with "Bird in the Dirt," a performance group that specializes in the conjuring of primal, indigenous forms.

This show, along with sculpture by Maria Velez, marks the gallery's 10th anniversary. It will continue at 2112 R St. NW through June 4. Hours are noon to 5, Wednesday through Saturdays. Diane Brown's N.Y. Gallery

Former Washington art dealer Diane Brown will open a gallery in the heart of New York's Soho district in September. The 5,000-square-foot space is located at 100 Greene St., near galleries owned by Ileana Sonnabend, Leo Castelli and other trendy bigwigs.

"I'm going with enough money to make it work," says Brown, who opened her first gallery on P Street here in 1976, after starting her career by holding Tupperware-style art parties. By 1980, she had established herself as Washington's leading dealer in contemporary sculpture, with space at 406 7th St. NW and a handsome loft at 52 O St. NW.

Brown will not disclose which sculptors will be included in her stable of a dozen, but it will include some Washington artists, she said. "Since I signed my lease, everyone wants to know who I'm taking. They'll have to come see." The International Art Fair

Harry Lunn, who will close his gallery here in July, has also established a public presence in New York, if not a permanent one. He is showing, through May, photographs made by Walker Evans in the New York subways between 1938 and 1941 at Books & Co., 939 Madison Ave.

For those who've wondered what Lunn will be doing with excess stock accumulated over 15 years of dealing here, he says, "There will be no fire sale at the gallery."

But, he adds, he has gathered "a quantity of fine 'decorative' etchings and lithographs from the storage bin" that will be "priced to sell" in the booth of dealer-printer David Adamson at Art 7, the International Art Fair scheduled at the Washington Convention Center June 2 through 6.

Included will be prints by Jim Dine, Adolph Gottlieb, Stanley William Hayter, Lars Bo, Walt Kuhn and Arthur B. Davies, along with John Grazier drawings and Michael Clark paintings.

Adamson plans to show new material in his booth at the fair, including prints recently produced in his own lithographic studio by Kevin MacDonald, Jim Sundquist, Ming Wang, Andrew Hudson, Michael Clark and Gene Davis. Most are currently visible in the David Adamson Gallery at 406 7th St. NW, along with a new suite of lithographs with tricky image-interplays by James Rosenquist, titled "High Technology and Mysticism." Gallery hours are 10:30 to 5, Tuesdays through Saturdays.