Painting with fire

The University of Minnesota, Morris, now practices the ancient craft of wood-fired pottery with a kiln of its own

A wood-fired plate by UMM alum Sam Johnson.

by Pauline Oo

From M, spring 2004

When you stick an unfinished pot into a wood-fired kiln, angry flames lick at it and wood ash rains down on it creating, if you're lucky, a glassy patina known as a "melting ash glaze." Geometric shapes may form on its surface as a result of shadows cast by nearby pots. With the building of a new kiln on campus, University of Minnesota, Morris, (UMM) can now introduce its students to the sensual and artistic magic of this millennia-old process.

Building the kiln was part of UMM teaching specialist Kevin Flicker's summer school class called Wood-fired Kiln Design and Construction. The class was partially funded by a UMM Educational Development grant for innovative curriculum and Flicker, a 1974 UMM alum, also received $12,000 worth of donated construction materials from several regional companies. Fuel for the kiln has come from trees uprooted during a freak summer windstorm.

"At most schools, students don't learn much about firing from a gas or electric kiln," says Flicker. "They make their pots and put them on a shelf for the teacher to load and fire. The actual firing process is fairly boring, highlighted by turning up a switch or valve every hour or two."

Wood-fired kilns, on the other hand, require the potter to cut wood, start a fire, and feed it often enough to generate up to 2,400 degrees Fahrenheit--almost seven times what you need to bake a cake. The fire, stoked around the clock for several consecutive days, needs a generous supply of wood, and the type and size of the wood is important.

During the inaugural firing at UMM last fall, 25 people spent four days feeding four cords of wood into the kiln, and after another seven days--in which the kiln underwent a cooling-down phase--the potters entered the dark chamber to unload their treasures. "I had never seen coloration and texture like that from any electric or gas kiln," says UMM freshman Megan Weisbrod.

Flicker, along with project consultant, potter, and UMM alum Sam Johnson, studied many kilns while designing the one for UMM and were particularly influenced by old Japanese kilns from the Bizen area in western Japan. Those kilns were designed to yield decorations on the pots from the firing process itself, rather than from applied glazes. "You literally paint with flame," says Johnson. "When I'm working with a wood-fired kiln, I'm touching something ancient. I feel connected to other potters who have worked with it before me."