Thursday, March 28, 2024

Special Clay at Herrontown Woods

We've had people of many sorts and interests visit Herrontown Woods--botanists, geologists, historians, birders, ecologists, herbalists, herpetologists, architects, a dry stone waller--all drawn to a particular facet of this multi-dimensional place. This post, about a ceramicist's visit, began with a conversation at one of our monthly May's Cafes at the Barden. Maybe we were talking about Toshiko Takaezu, the celebrated ceramicist who is said to have gathered clay for her pottery at Herrontown Woods, but in any case someone told me that there is an artist at the Arts Council of Princeton who is sampling clay from various locations in our region. I contacted Adam Welch, executive director of the Arts Council and himself a potter, for more information.

That someone canvasing clay in NJ turned out to be Ryan Lilienthal, the Arts Council's current resident artist. He was enthusiastic about visiting Herrontown Woods, and as it happened, he visited Toshiko's studio the day before coming. 

He brought a friend along, and I showed them a few places where I had encountered particularly dense clay. Ryan began digging, and was soon demonstrating "the worm test," in which soil is rolled into the shape of a worm. If it holds together, that means the soil's clay content is high. 

I have grown to love and respect clay, for the very reasons many gardeners dislike it. The denseness of clay slows water's passage through it, allowing water to linger on the surface. That water, if the clay is sufficiently dense, will form vernal pools in spring where frogs and salamanders can gather to breed and lay eggs. Many native plant species also thrive in areas where clay keeps the ground wet. Sedges, rushes, and wildflowers like hibiscus, ironweed, and cutleaf coneflower all thrive where sunlight reaches the wet ground made possible by clay. 

Ryan proved to be a kindred spirit. A longtime painter, he has in recent years taken a passionate interest in clay, and reveled in the mud that Herrontown Woods holds in abundance.

That clay comes in many colors--usually brown, but sometimes grey, and sometimes with an orange cast that reflects a higher iron content. Understanding clay in its many forms, and the forces that led to its creation from the underlying rocks, is a lifelong study in and of itself.

Ryan collected samples from several locations, placing shovel fulls in large ziplock bags, to take home and test. 

One of the tests he conducts is to make a brick out of the collected clay. A week after his visit, he sent me a photo of one of the bricks made out of Herrontown Woods clay. 

Where might this exploration of local clay lead? A possible next step that Ryan talked about is pit firing pottery, that is, using the ground as a kiln to fire the clay. 

In so doing, Ryan would take us back, or forward, to an era when people interacted with nature by making stuff. A government website about New Jersey's geology provides a dramatic contrast between how clay was used in the past, and how it is mostly used now to, alas, cover mountains of trash:
Back in the day, hundreds of thousands of tons of clay dug in Central New Jersey was used to make bricks, pottery, roofing tile, and other useful products. Most of the clay that is currently mined in New Jersey is used to seal the tops of landfills. 

The purpose, by the way, of putting a thick layer of clay on top of a landfill is to prevent rainwater from seeping into the pile of trash, where it might then flow down through the garbage and into the underlying aquifer, picking up toxins along the way. Instead, rain hits the impervious clay and runs off the landfill, keeping the contents dry and the groundwater supposedly unpolluted. Nice to think of the clay in Herrontown Woods' soil as cradling the rain in vernal pools for slow infiltration, rather than shedding it.

The "cultural zone" of Herrontown Woods--the area between the Veblen Cottage, Veblen House, and the main parking lot--was historically used to make stuff. The land was cleared to grow food. Boulders were quarried for trap rock. Trees were harvested for firewood or used for building. Though I'm glad they stopped hauling away rocks from the ridge (we like our boulder-studded forest!), there's something honest about local harvest. Now, we manage the land for native diversity, which is important, but it's also very satisfying to find utility in the landscape. We cut boards from fallen trees to make a boardwalk, and have started to grow some food near Veblen House. We collaborate with nature at the Botanical Art Garden. What a fine thing if clay, cursed by so many gardeners, becomes yet another source of art, utility, and wonder at Herrontown Woods. 

To get more of a sense of how clay was mined and used historically in Princeton, read Clifford Zink's history of Jugtown, in which he describes the use of local clay to make bricks and pottery in the Jugtown neighborhood of Princeton.