Lessons On A Forest Garden In Three Different Climate Regions
Since 2009, I have learned from three forest gardens in three different forest habitats. In 2009/2010, I lived in the Coastal Douglas Fir zone on the Sunshine Coast of British Columbia, deep within a complex mix of secondary and old growth cedar, fir, Arbutus, and red alder trees, shading salal and evergreen huckleberry shrubs. In 2011/2012, I lived in a dry wheatgrass/fescue meadow surrounded by Ponderosa pine and sagebrush in Western Montana. Then in 2012 I came to a diverse commercial fruit orchard planted in patches within live oak/pine forest in the Sierra foothills of northern California.
Forest farming is a different mindset from agriculture!
Generally agriculture in North America has come from the grass-based plains and meadows of Europe. It relies heavily on cultivated grasses, or grains, and animals who graze on grasses. When I was in my early twenties and an intern at the Land Institute in Salina, Kansas, I was drawn to horticultural societies and agroforestry. At the Land Institute, we were envisioning a food system modeled after the diverse mix of perennial grasses and flowering plants living together in the prairie. This agriculture would be a perennial polyculture with its roots deep into the rich prairie soil undisturbed by tillage and the herbicides, pesticides, and fertilizers humans created to subsidize our tillage, disturbance-based agriculture. I kept wanting to talk about fruit and nut trees and the exciting diversity of small meadows at the forest edge. In exasperation one day, Wes Jackson, cofounder of the Land Institute, told me that when people get serious about agriculture, they plant grains. He was right, especially in a world with burgeoning population growth. So, for the next 25 years I studied, researched, and taught horticulture/agriculture and produced organic vegetables and fruits on my farm in Montana, with as little tillage as possible. I added legume living mulches in between my straight rows of vegetables, fruit bushes, and fruit trees. I called my reduced tillage, increased diversity system agricultural ecology. For videos and articles about my 17 years experimenting with agricultural ecology, living mulches, green manures, and conservation agriculture in Montana go to Conservation Farming, and Biodesign Farm research. But, in 2009, I had a chance to go beyond my conventional organic techniques and learn from listening to a forest.
Our human tendency is to chop down excessive plant growth, clear away brush, control the wildness, make nature neat. But, I knew from experiments with agroecology in Montana that if we do too much, we inherit the jobs of the organisms we get rid of and are forced to make and add fertilizer, apply fungicides to control disease, and insecticides to kill insects. There is also much research on the interactions of healthy functioning forests. Scientific research shows that the spatial, or structural, diversity in a functioning forest, what we call the "uneven texture" in a wild forest, enhances bird and insect diversity and balances pest outbreaks. In other words, the shape of a forest, from top to bottom, helps it maintain its own pest resistance. Our agrocecology experiments in Montana showed us the same thing when we diversified the below-ground and above-ground plant height and texture in our vegetable fields. Pest problems disappeared over time as a larger number of generalist predators and parasites came to live on the farm.