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Keepers of the Oaks

Modern Americans may preserve California better than Native Americans did.

By Glen Martin
Aug 1, 1996 5:00 AMNov 12, 2019 6:44 AM


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One Thursday in November 1856, a Marysville Herald reporter visited the native people of Yuba City, California. It is not necessary for us to speak of their filth, and other circumstances connected with their miserable condition, he wrote. We would rather ask, is there no method by which they could be made to improve themselves? In their council hall, as it is called, but more properly a deep dirty pit, with poles for bunks, and everything else in keeping, we saw three chiefs, and a dozen or more captains, large, muscular men, squatted on the ground by bowls of acorn mush, lazily lying in their bunks, with a few unraveling a red comfort, to bedeck themselves for some imbecile fandango. There is to us something so utterly abhorrent in the thought that they must waste away life like that in inactivity, or by the more speedy process of dissipation, to which they are becoming addicted. Could not those who live among us by some law be required to bind out their children to farmers and others, for a given period, so as to make them useful, and thus induct them to habits of cleanliness and industry?

While twentieth-century anthropologists emphatically reject the reporter’s moral judgments, until recently they did agree that California’s natives were no farmers. They held that California, like most of North America during neolithic times, was for millennia a wilderness populated by hunter-gatherers. Before Columbus landed, they believed, American agriculture was confined to southwestern and eastern tribes, who cultivated beans, corns, and squash. California’s natives neither sowed nor reaped. They appeared to fit the hunter-gatherer profile precisely, subsisting entirely on what nature offered them--grass seed, salmon, game, and acorns.

But recent research suggests that California’s natives weren’t waiting for the manna of acorns to fall from the trees into their hands. Instead, anthropologists and ethnographers increasingly view the state’s first inhabitants as agriculturists. True, they didn’t plant grains or vegetables or cultivate fruit trees, but they employed intensive horticultural practices to ensure that oak trees would flourish. In their own way, they farmed oaks.

Anyone who has ever nibbled on a raw acorn might doubt that the things are edible, let alone worth cultivating. But once the nuts have been processed to remove their tannins, which are responsible for the acrid taste, acorns are an impressive source of nourishment. With up to 18 percent fat, 6 percent protein, and 68 percent carbohydrate, depending on the species, they compare favorably with modern grains--wheat and corn register about 2 percent fat, 10 percent protein, and 75 percent carbohydrate. The acorns’ richness and abundance made them the staff of life for California’s natives.

That abundance was largely the result of the careful use of one important tool: fire. Californians certainly didn’t practice agriculture in the traditional sense. They didn’t domesticate the oak, as Mediterraneans did the almond, by selecting and planting nuts with useful characteristics. Oaks may have to grow 20 years or more before yielding a good acorn crop-- hardly a desirable trait in an orchard tree. But by employing fire as a horticultural tool, California’s natives achieved a singular feat. No other people have ever bent the recalcitrant oak so effectively to the human will. Simply put, regular low-level wildfires encourage oaks in California. Stop the fires, and plants with low fire resistance, such as shade-tolerant conifers and brush, dominate. This fact, researchers are recognizing, was not lost on California’s Indians.

Historical descriptions support this conclusion. Spanish missionaries in the eighteenth and nineteenth centuries, and American settlers in the nineteenth century, reported that natives regularly set fire to grass and forestlands. As one woman of the Karok tribe explained in 1933, Our kind of people never used the plow. . . . All they used to do was burn the brush at various places so that some good things will grow up. . . . And sometimes they burn where the tan oak trees are lest it be brushy when they pick up the acorns. . . . Some kinds of trees are better when it is burned off. They come up better ones again.

Fires helped keep the trees healthy, ensured bigger crops, and made it easier to gather the nuts. Naturally occurring oak seedlings form very thick stands, says Pamela Muick, a San Francisco State University ecologist who is conducting an oak habitat study at the Elkhorn Slough Sanctuary on Monterey Bay. Burning thins them out, creating a density pattern that allows trees to grow large, healthy, and easy to walk through.

As late as the 1960s, recall surviving members of California’s tribes, people were setting fire to the forests every year, just after the midfall acorn harvest. One member of the Wukchumni Yokuts tribe told a researcher that the burning was necessary to rid oak lands of acorn pests. If left unchecked, filbert worms and weevils can destroy up to 95 percent of the acorn crop dropped by individual trees, agrees Kat Anderson, an ethnobotanist with the American Indian Studies Center at ucla, who for the past ten years has been studying the influence of Native American cultural practices on plant distribution. Fire breaks the life cycle of both pests, ensuring much better crops.

Setting fires wasn’t the only native practice that kept oaks healthy. The preferred method of gathering acorns was to knock them off the trees with long, flexible poles, says Anderson. But when they were knocking acorns off, people would also knock off dead or diseased wood, a practice that stimulates new growth. I’ve talked to elders who say that the traditional knocking off of old wood has the same effect as a big snowstorm, which breaks off dead and weak wood--it’s good for the trees.

California’s native people also performed another task critical to successful agriculture: weed removal. Galen Clark, a nineteenth-century Yosemite Valley resident and one of Yosemite National Park’s first nonnative caretakers, reported that Indians diligently pulled cottonwood seedlings from meadows surrounding oak groves. Keeping those meadows open protected the oaks from harmful crown fires and encouraged light surface fires that would burn out only the undergrowth. Other modes of weeding may have been practiced as well, though solid evidence is lacking. I’ve found that a quick removal of the grass around each seedling oak in the spring contributes tremendously to their vigor, says Muick. Annual grasses are serious competitors with young oaks for water and nutrients. A few seconds of weeding for each tree during the first few seasons is all it takes--they respond tremendously. I can’t believe that similar empirical observations weren’t made by indigenous people.

Fire, though, was the primary horticultural tool. It was easily and quickly employed, and it could be used to work many acres. Applied regularly over a vast area for centuries, fire became a force as profound as weather in its impact on regional ecology.

Essentially, large portions of California tend to go one of two ways, depending on whether fire regularly burns across the landscape. In the Sierra foothills and other portions of the north, the choices are forests of conifers--dominated by incense cedar and white fir--or savannas of oaks. In the coastal central and the southern parts of the state, the choice is chaparral or oaks. Fires favor oak habitats in both areas. If fires aren’t regularly introduced, the oaks gradually disappear.

For the past 70 years, the fires have been stopped, by California’s fire-fighting agencies. As a result, much of California’s forestland looks very different from the way it looked when European explorers first arrived. As late as 1844, when explorer John C. Fremont led an expedition to the Sacramento Valley, he described the north state foothills as smooth and grassy; [the woodlands] had no undergrowth; and in the open valleys of rivulets, or around spring heads, the low groves of oak give the appearance of orchards in an old cultivated country. Similarly, a nineteenth-century visitor to the middle fork of the Tuolumne River near Yosemite Valley found it like an English park--a lovely valley, wide and grassy, broken with clumps of oak and cedar. Fire made the difference.

However much benefit the native people derived from oaks, it appears the stately trees weren’t their original reason for burning off the land. Natives may have been setting fires in California for at least 5,000 years, speculates Anderson, judging by how long fire-loving giant sequoias have been expanding their range. But California’s Indians didn’t begin relying on acorns until at least 1,000 years later.

At first, acorns seem to have been a food of opportunistic significance, not a staple, says anthropologist Helen McCarthy of the University of California at Davis, who has been studying the relationship between California’s native people and plants for more than 25 years. Natives buried them for a long time, and groundwater slowly removed the tannins. Then, we think, they were eaten one by one. Ambitious acorn processing, she says, is associated with stone mortars and pestles--and those that have been recovered are 4,000 years old at most. It’s just my opinion, says McCarthy, but that leads me to believe acorns became a staple part of the diet around 4,000 years ago. For some parts of California, Anderson puts that date even later: 1,000 years ago.

Then why were California natives setting fires, when they weren’t using acorns in quantity? Archeologists have found milling stations where no oaks grow, says Anderson, so it’s apparent they were grinding something other than acorns. All evidence points to seeds of grasses and forbs--broad-leaved herbaceous plants--which also increase with burning. Grass and forb seed remained an important secondary food source throughout the acorn era. It now appears that the first thing that was important to natives in the oak and grass savannas they created through fire was the grass. The emphasis on acorns came later.

The mortars and pestles used to grind grass and forb seed into flour, which is called pinole, typically weren’t as massive as those required for acorns, observes Anderson. Pinole mortars were usually small enough to tote around, and the pestles were relatively small. But for acorns, you need big pestles and bedrock mortars--holes dug into the living rock, deep enough to allow you to pound the acorns vigorously without having the meal scatter everywhere. We only start finding those between 450 and 1,650 years ago. That’s pretty significant, considering that Indians have lived in California for at least 10,000 years.

As well as encouraging grasses to grow, fires created ecotones-- varied ecological communities within a relatively small area. Wildland areas in California that haven’t burned in a long time are low in species diversity, says McCarthy. In the chaparral zones of California, for example, you can have huge expanses dominated almost completely by chamiso, a resinous shrub. On the other hand, regular burning produces an explosion in the diversity of plants. Such burning, she explains, creates edges in the landscape--places where different communities can take hold. From the Indian perspective, that would be very valuable, because food sources would increase in both quantity and variety. Deer were particularly important to California’s natives, and they like burned landscapes, where there’s abundant forage.

Some of the plants that grew in burned areas were important not just as food but for making tools. California natives relied on deer grass and shrubs such as redbud for their basketry, which was used for everything from storing food and goods to cooking: acorn gruel was prepared by dropping heated stones into a basket containing a cold mixture of pounded acorn meal and water. Such baskets were marvels of aesthetics and function; cooking baskets, obviously, had to be so tightly woven that they could hold water. But the materials needed didn’t just grow willy-nilly--they had to be stimulated through fire. Redbud’s immediate response to burning, for example, is to send out an abundant growth of straight new shoots of the dimensions needed for baskets. Today, Maidu, Miwok, and Mono basket makers prune individual redbud bushes to get the shoots they need, says Anderson, but they say that the traditional method is burning.

While it seems likely that tribespeople first burned for grass seed and basket materials rather than acorns, it’s not clear what made acorns assume such an important role in the native diet. Compared with grass and forb seed, acorns are tough and time-consuming to prepare. A few swipes with a pestle in a mortar is all that’s necessary to turn most herbaceous seeds into meal, but acorns take intense pounding. And the resultant meal still has to be leached of tannin. This was often accomplished by packing the meal into basins scooped from clean sand and pouring water over it several times. Sometimes cooks added yet another step, congealing the mush into a kind of bread by immersing it in cold water.

Though McCarthy doesn’t know what made California’s natives start looking to oaks as their primary food, she is sure of one thing: Generally, people don’t work any harder than they have to. We don’t know if they turned to acorns big-time because a growing population made it necessary, or if the dissemination of the acorn processing allowed the population to grow because more food became available. One way or the other, though, oaks ended up supporting a lot of people in California.

One well-regarded population study conducted in the 1950s correlated food resource bases, such as acres of oak groves and miles of salmon spawning grounds, with regional native populations, and came up with 350,000 people. Another study completed the following decade relied on Spanish mission records and native village reports, and put the population at 320,000. Either way, it’s clear that at the height of its acorn- processing culture, California supported what was an anomalously high population density. By contrast, the Great Plains--stretching from mid- Canada to the Gulf of Mexico--supported no more than 150,000 people during the late seventeenth and eighteenth centuries.

With so many people depending on oaks, it’s not surprising that a complex of laws and lore grew up around them. For example, John Hudson, a northern California ethnographer, wrote early in this century that favored trees were marked to distinguish ownership: An acorn-bearing tree was undisturbed when guarded by four sticks placed against it. An Indian believes it is sure death to disturb the sticks or their wards.

Particularly valued trees could have several owners, each of whom had specific rights, observes historian Malcolm Margolin, the publisher of Heyday Books in Berkeley, which specializes in texts on California natives. One person, for example, may have had the acorn franchise. Another may have held rights to hunt woodpeckers on the trees. Another would have had rights to collect deadwood for fuel.

Just as some individual trees were more valuable than others, so were some of California’s 23 oak species. Black oak is still the favorite among traditional tribal members, observes Walter Koenig, a research zoologist with the University of California at Berkeley whose work with acorn woodpeckers has led him into the related field of acorn production patterns. It has a nice big nut, it’s high in fat so it’s really tasty, the meat separates easily from the husk, and it stores well. Nevertheless, observes Koenig, if black oaks weren’t producing well one year, the tribes would use varieties that were. Oak diversity would have been insurance against hunger.

When white settlers took over the land where California’s tribes lived with their oaks, they didn’t abolish burning all at once. Early ranchers favored fires because they stimulated the bunchgrasses livestock loved, and acorns were a rich winter feed for cattle. By the 1920s, however, widespread wildland burning ground to a halt, the result of an aggressive fire-prevention policy instituted by state and federal forestry agencies (though some native people continued to burn on the sly until the early 1960s). Over the past seven decades, the conifers and brush have encroached across the state, and the oak savannas have retreated. Today the Sierra Nevada are cloaked with white fir and incense cedar; the coastal range is swathed in brush.

But things are again changing. The U.S. Forest Service and the California Division of Forestry and Fire Prevention have turned to a process called prescription burning to remove buildups of woody detritus and improve woodland diversity. Prescription burning uncannily mimics the native use of wildland fire. Forest Service fire scientists minutely monitor air temperature, humidity, and wind direction before igniting a burn, to make sure that it falls within the fire prescription. They want a blaze hot enough to destroy downed wood, but cool enough so little harm is done to standing timber. California’s Indians had the same goal. Natives typically burned during the fall, says Anderson. The cool temperatures and high humidities produced low-lying fires that burned out the deadwood without harming the trees. They would burn river drainages with different exposures at different times, depending on the kind of burn they wanted.

Each of the last five years has seen bigger Forest Service budgets earmarked for prescription burning. And California’s natives are part of that process. There’s a real resurgence in native awareness in this state, and concern for oaks is a big part of it, says Lorrie Planas, a member of the Western Mono and Choinumni tribes and a heritage resource specialist for the U.S. Forest Service Kings River Ranger District, in the Sierra Nevada. Planas oversees a Forest Service burning project on black- oak groves near the Kings River. First, says Planas, we want to invigorate the groves and prevent encroachment from other species. Second, we’re maximizing access to the acorn crop for local tribespeople. The burning clears the underbrush so people can get at the acorns more easily.

So popular are acorn-based foods becoming among California’s tribes that the merits of relative preparation methods are actively debated. Some people feel that the only way to prepare mush is the traditional way--grinding the acorns with stone implements and cooking them with hot rocks in basketry, says Planas, laughing. They say it makes the mush taste much better--more nutty and toasty. But most people opt for modern convenience--food processors, colanders, gas stoves, and metal cookware.

The growing awareness that California was a vast nut orchard for thousands of years changes the definition of wilderness. Oak landscapes were manipulated landscapes. They were very rich biologically because of their patchiness--their differences from one small area to another, explains Anderson. Ironically, the state’s ecosystems were far richer than if there had been no human influence. California’s wildlands are losing their biodiversity, their patchiness, because there is no longer a native influence on the land.

Anderson thinks that the evidence of historic native environmental impact in California will ultimately cause a sea change in the way ecological processes are defined. One of the most significant environmental disturbance factors in North America has been indigenous peoples. In ecological circles, we’ve begun to change the classic metaphor for nature from ‘balance’ to ‘flux.’ But we need to recognize that the flux was caused by native people. Horticultural practices have been an inextricable part of nature in California and other parts of the continent since natives first arrived. California is more of a wilderness now than it ever was. It’s like a feral garden, one that has gone to weeds through neglect.

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