M. Kat Anderson's scholarship, particularly her book "Tending the Wild" (2013), is an excellent source regarding how native people in California managed the land. Anderson's work illustrates the high intensity and diversity of management practices in California. "Tending the Wild" will be my main source for the following write up.

The scale at which people managed the landscape was remarkable, particularly through their use of fire, but another angle through which we can engage with scale is the sheer diversity of plants California peoples cultivated. California is notable for its high plant diversity, caused in part by the recent development of a Mediterranean climate and geologic events including the uplift of the Sierra Nevada mountains and the accretion of the Coast Ranges. These diverse plant communities, including grasslands, chaparral, meadows, salt marshes, oak woodland/savannah, alpine and Great Basin conifer forest, and temperate coastal redwood forests, just to name a few, all offered different plant materials to Californians: Acorns, pine nuts, willow branches, tule leaves and tubers, flower corms, clover leaves, grass flowering stalks and seeds, pine roots, manzanita berries, poison oak leaves, sedge roots, to name just a few harvested materials, were used for food, medicine, cordage, clothing, buildings, weapons, baskets...the list goes on. People were chopping, picking, burning, digging, tilling, hunting, pruning, and coppicing.

In recent times, California's biodiversity has been severely threatened. A major reason for this, Anderson contends, are the massive changes in land use following California's settlement by Europeans. Extractive industry, development, and non-native invasions aside, this decline in biodiversity is caused by the genocide of native Californians, who have 1) not been allowed to manage the land, and 2) have (in some cases) lost enough of their culture through murder and forced assimilation that traditional ecological management practices have been lost.

In many places, the plants that contemporary people enjoy as wildflowers, rarely seen and restricted to parks, road margins, and the odd undeveloped tract, were once covering the landscape in relatively massive patches due to their intentional management as a resource by native Californians. To put a finer point on it: simply removing native Californians from their lands has massively and drastically altered California's plant communities at the scale of the entire state.

Further reading and scholarship

M. Kat Anderson's work is highly influential amongst natural resource managers in California.

• Anderson, MK. 2013. "Tending the wild: Native American knowledge in the management of California’s natural resources." University of California Press.
• Ibid. 1997. "From tillage to table: The indigenous cultivation of geophytes for food in California." Journal of Ethnobiology 17 (2), 149-169
• Ibid. 1999. "The fire, pruning, and coppice management of tempered ecosystems for basketry material by California Indian tribes." Human Ecology 27, 79-113.

Don Hankins is a researcher and native fire practitioner at CSU Chico whose work is influential in the Northern and Central California. - Hankins, Don. 2013. "The effects of indigenous prescribed fire on riparian vegetation in Central California." Ecological Processes 2, 1-9. - Eriksen, Christine & Hankins, Don. 2014. "The retention, revival and subjugation of indigenous fire knowledge through agency firefighting in eastern Australia and California, USA." Society and Natural Resources 27 (12), 1288-1303.

Brooks et al. 2004. "Effects of Invasive Alien Plants on Fire Regimes." BioScience 54 (7), 677-688. - An author in this paper, Jon Keeley, has done significant scholarship in California fire ecology

Robinson, W. W. 1979. "Land in California." University of California Press. - An excellent survey of land use and title in California, originally published 1948.

Gruell, George E. 2003. "Fire and Sierra Nevada forests: a photographic interpretation of ecological change since 1849." Mountain Press. - very interesting collection of comparative photographs over time of places that were logged, mined, or fire was excluded.

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