In our last post we told our readers about the usefulness of non-native plants which are closely associated with human civilization and are therefore found everywhere, but are considered weeds. We don’t wish to leave our readers with the impression that native plants are not at least equally useful, so we will counter-balance our last post with this report based on a book about California Native Americans: Tending the Wild: Native American Knowledge and the Management of California’s Natural Resources. (1) The author, M. Kat Anderson, is the national ethnoecologist of the United States Department of Agriculture’s Natural Resources Conservation Service and an Associate in the Department of Plant Science at UC Davis.
Aboriginal societies have been categorized by anthropologists as either hunter-gatherer or agricultural societies. California Native Americans were considered hunter-gatherer societies because they were not sedentary, tied to a specific site where they tilled the land to grow crops, and they had no domesticated animals. Tending the Wild challenges this categorization based on an exhaustive survey of the land management practices of California Native Americans. The author proposes a middle-ground between the dichotomous categories to reflect the many ways in which Native Americans essentially gardened wild plants to produce their food and other utilitarian objects, while also acknowledging the seasonal mobility of Native American society.
Fire was the essential tool
Million Trees has reported many times that California Native Americans intentionally set fires, but until reading Tending the Wild we did not appreciate how essential fires were to their culture, nor did we understand the many purposes for which fires were set. Here is an incomplete list of the many reasons why Native Americans set fires:
- Fires maintained grassland by eliminating shrubs that naturally encroach on grassland in the absence of fire.
- In the absence of fire, thatch of dried grass accumulates when grasses die back during the dry season. This thatch retards the germination of a new crop of young grass.
- Young grass which sprouts after a fire is attractive to grazing animals which were hunted. Young grass was also preferable for basket-making because it is straight and pliable.
- Fire reduces shrub vegetation which competes with grasses for light and water. Land cleared by fires was then seeded with the plants most useful to Native Americans.
- Fire recycles nutrients in the soil.
- Fire was used to smoke small mammals from their burrows.
- Fires were used to corral grasshoppers and other insects considered edible for harvesting.
- Fire was used to reduce insect populations that feed on the plants eaten by Native Americans. For example, the duff beneath oaks was burned before acorns fell so that acorns were not eaten by insects.
- Fire was used to germinate seeds of the many species of native plants that require fire for germination.
- Periodic fire was considered a means of preventing wildfires fueled by accumulated dead vegetation.
Other land management methods
Fire was one of many management methods used by California Native Americans to foster the plants that were most useful to them. In some cases, these practices maximized their food sources and in others they produced useful materials such as those needed to make baskets or plants thought to have medicinal properties.
Tending the Wild reports that 60-70% of the diet of California Native Americans was from plants. Miwoks report using 48 species of plants for fresh greens compared to just a dozen salad greens typically found in a modern market. California Native Americans ate 15 of 31 native clover species. Clover seed was broadcast-seeded onto burned ground because it improved the fertility of the soil by restoring nitrogen to the burned soil.
Baskets were equally important to their culture. Every family typically had 22 different types of baskets for a variety of purposes such as storage, food gathering, beating seeds from plants, cooking, water storage and transport, fish traps, small-animal traps, etc. Seventy-eight plant species were used by California Native Americans to make these baskets.
Here is an incomplete list of the methods used to foster the plants most useful to California Native Americans:
- The seeds of favorite plants were planted to be available close to living quarters. Native tobacco is an example of a plant found around Native American settlements, presumably planted there.
- The seeds, bulbs, corms, rhizomes etc., of favorite plants were collected and transplanted close to settlements.
- Bulbs, corms, roots, rhizomes were harvested selectively to preserve the plants which were stimulated by the thinning of the plant.
- Fields of useful plants were weeded to create monocultures that made harvesting more efficient.
- Plants were pruned and coppiced to maximize fruit production.
- Plants were pruned to produce the straight twigs and grasses useful to make baskets and arrow shafts.
- Plants were irrigated to promote growth and maximize fruit production.
- Plants were treated by cooking, soaking, etc., to remove toxins so they could be safely eaten.
Impact on the landscape
Over the thousands of years that California Native Americans practiced these land management practices, the landscape was altered by them:
- Plants that did not tolerate frequent fires died out, creating a landscape that is dominated by plants that are adapted to fire. Jon Keeley (USGS) informs us that over 200 native plant species are “fire endemics,” requiring fire to germinate and dying out within a few years after a fire. (2)
- The Europeans arriving at the end of the 18th Century found a landscape dominated by grassland because repeated fires prevented succession to shrubs and forests. The absence of shade produced a landscape of native plant species that require full sun.
- Forests were open and park-like with little understory, which had been repeatedly cleared by frequent fires.
- The plants which were most useful to Native Americans were more likely to survive than those that were not useful because they were tended and competing vegetation burned or weeded.
- The natural ranges of the plants which were useful were altered by the land management practices of Native Americans. They were transplanted and grown from seed where they were accessible to the community.
What are the implications for ecological “restorations?”
The landscape selected by native plant advocates as the goal of ecological “restorations” is the landscape that existed in 1769 when Europeans first laid eyes on San Francisco Bay. Now we know that it was a landscape that had been altered by thousands of years of occupation and cultivation by California Native Americans. There are at least two major flaws in the selection of this landscape as the goal of “restoration:”
- Native ranges reflect the choices made by the Native Americans. They do not necessarily reflect the forces of nature. The modern obsession with “where plants belong” is based on a fantasy of why plants were found where they were when Europeans arrived in California.
- The land management practices of Native Americans are no longer being practiced, which means that the plants they preferred are no longer receiving the care that ensured their survival in the past. Humans no longer set fire to the landscape every year. Therefore, the landscape has changed and will continue to change to correspond to changed practices:
- Grassland is succeeding to shrubs.
- Shrubs are succeeding to forest.
- Plant species that require fire to germinate their seeds are dying out. For example, several species of Manzanita are now endangered because they cannot be propagated in the absence of fire.
- Plant species that require full sun for their survival are dying out because they are now shaded by shrubs and trees.
The relationship between humans and nature has changed since California was occupied solely by Native Americans. Consequently, nature has changed in ways that reflect how humans now use the land. The author of Tending the Wild acknowledges that her book conflicts with the goals of ecological “restoration:”
“If restoration is aimed at returning ecosystems to the condition in which they existed before Western settlement degraded them, then that condition is surely not an entirely natural one. As we now know, many of the classic landscapes of California—coastal prairies, majestic valley oak groves, montane meadows, the oak-meadow mosaic of Yosemite Valley—were in fact shaped by the unremitting labor of generations of native people. Moreover, these and other communities were managed intensively and regularly by these people, and that many have disappeared or changed radically in the absence of management shows they were not self-sustaining.” (1)
In our next post, we will think about how our relationship with nature has changed and what that means for the future of the management of our remaining open spaces. Given this revised understanding of the “native” landscape, how must we revise our goals for ecological “restoration?”
- M. Kat Anderson, Tending the Wild: Native American Knowledge and the Management of California’s Natural Resources, University of California Press, 2005 (This is the source of most of the information in this article.)
- Jon Keeley, et. al., Fire in Mediterranean Ecosystems, Cambridge University Press, 2012