submitted by Philip Fry
Not long after “CO2 Down to Earth 2” appeared in the NGT, I dropped in to see friends who live just down the road from us. They had seen the article and I was complimented on the picture; then came a pointed question: “I hope you don’t want me to dig holes in our lawn.” It was a moment that I dreaded, for I realized that the lawn question would seem to be a direct attack on their values, but I knew that it would come up some day. I felt conflicted and responded rather awkwardly: “yes and no, that is something I am suggesting one might want to do.”
The problem is that my friends’ grounds are beautiful, and in spite of my concern about the need to act urgently about the climate crisis, I continue to admire their garden’s expansive, sweeping lawn which is framed by borders of carefully selected and tended flowers and scrupulously laid out rectangular vegetable beds. In the background, there stands a second or third growth of woods. Who was I to call such work and expertise, such care, into question? I later found out that their woods cover at least two-thirds of their property, more than compensating for the lawn. Ouch! My friends are indeed working in the right direction. My point is that solutions to the environmental crisis will involve differentiation and personal decision making. But stabilizing the carbon cycle by sequestering excess CO2 in soils is nevertheless a shared, central issue.
Transforming our regional soils into effective carbon sinks will be a challenge. From a geophysical point of view, our soils are young, fragile, and nutrient poor. About 12,000 years ago, as the glacier that covered our region receded, the ocean invaded, forming the Gilbert Gulf of the Champlain Sea. The movement of the waters sorted and layered glacial deposits of gravel, silt, sand and clay, building wave-like overlapping layers on the limestone bedrock. After the waters withdrew, it took millennia for plant and animal life to adapt to the harsh conditions; eventually the area developed into a part of the Great Lakes-Saint Lawrence mixed forest. Various species took up their location where the deposits of mineral out-wash suited their particular requirements, slowly initiating self-sustaining nutrient cycles with a mix of the local parent minerals with decomposing organic material. In our location, where sand, hard-pan (a mix of clay, silt, and dispersed stones) and gravel overlap and dominate, few available mineral nutrients are present, so the soil remains fragile and of poor fertility.
There is archaeological evidence that management of soils and crops was introduced by indigenous peoples about 1,000 years ago. After choosing a suitable location, they probably used a slash and burn technique, first girding the trees, then leaving them to stand and dry before burning out the area. The resulting ash and charcoal added a temporary supplement of carbon, phosphate and trace elements to the nutrient poor soil. Companion plants known as “the three sisters” – beanswhich fixed atmospheric nitrogen, corn which provided elevation for the climbing beans, and squash which trailed on the ground, moderating the impact of the weather – were grouped throughout the garden and complemented by sunflowers and tobacco. The soil was nevertheless exhausted for farming purposes after a few years of good production. When this happened, the depleted fields were abandoned, and as new clearings were opened, the old clearing regenerated, becoming host to an enhanced diversity of species. The result was a long term, sustainable use of otherwise fragile and relatively nutrient poor soils.
Should we not include these facts in our thoughts as we seek reconciliation with those whose land we now inhabit?
Most climate scientists situate the onset of the environmental crisis at the industrial revolution in Europe. Is it not possible that in our region it began with colonization, local land allotment, and the influx of settlers who introduced European agricultural methods?
Working on that must be left for the next instalment of CO2 Down to Earth. Meanwhile, please contact me at [email protected] with your comments.