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Wildlands, Agrifolia, and Enchanted Landscapes

A few years ago, an oak by the open-space entrance lost a large limb. The tree, apparently healthy, was damaged by the strong winds and heavy rains of El Niño.

This was a magnificent old oak, probably over 200 years old. Since moving here over eleven years ago, I must have passed by that oak hundreds of times and each time I noticed it. The sentinel to our open space, it stood only about a hundred yards from the cattle guard entrance gate that marked the barrier between the housing subdivision and the more natural wild lands beyond. Standing alongside the track, all animals, human or otherwise, had to pass by this oak. And in that passing, one’s deeper being, whether consciously or subconsciously, acknowledged its greatness.

This particular oak, like the majority of our oaks along the north coast of Marin County, is a Live Oak, or Quercus agrifolia. There are nine species of tree oaks (there are also some shrub oaks) in California. Species refers to the second part of the name, in this case ‘agrifolia’.

When I looked up ‘agrifolia’ (always capitalize the Genus; never the species) in the Guide to Word Roots for Scientific Names, ‘agri-‘ oddly enough, has two meanings. The first is Latin for field. This makes sense, like the word agriculture. Coast Live Oaks grow in the open coastal plains. They are not found directly along the coastline, but across valleys and hillsides, as far inland as 50 miles, and north as far as Mendocino County, and south to northern Baja. Although they grow near watercourses and in rocky canyons, sometimes packed like groves, the oaks that dot our open ranges, especially during winter when the hills are green, leave the greatest impression. Early California visitors wrote about the mystical beauty of this tree and its enchanted landscapes.

Another translation of this prefix comes from the Greek, meaning ‘wild, fierce’. Quercus agrifolia has a wide and helmet-like canopy, rather than upright like the valley oak, which also grows in Marin. It readily stump-sprouts after being cut, broken or fire-damaged, and so it is frequently multi-trunked, some limbs venturing horizontal, while others grow vertically. It’s gnarled and massive appearance looks especially haunting at night; hence it’s ‘wild, fierce’ name. ‘Folia’, of course, means foliage.

Once the large limb broke off, a pathway opened for various fungi to enter. Because these fungi have evolved over millions of years with the oak, they have developed immunity to the strong chemicals, called tannins, the tree manufactures to ward off pests. When the fungus finds a path of entry, the oak is doomed. The organisms work their way into the heartwood, creating passageways for insects and other diseases that finish off the oak.

The oak doesn’t go down without a fight though. As the fungus works it’s way into the wood, literally eating it as we eat food, the oak puts down a barrier of live and dead wood cells. The fungus responds and tries to get past this barrier. The oak responds by putting down more wood, and so the battle goes.

There’s a saying that oaks seem to “live for about a hundred years and then die for a hundred years.” This beautiful oak was slowly dying. With each passing season, new limbs fell. During the winter of El Niño, each new heavy storm brought the mighty oak a little closer to its knees. Day after day I’d walk into the hills to find the tree transformed and disfigured. Conchs, large woody mushrooms that look like odd wavy shelves of dark extruded wood, began to appear on the tree. These conch fungi mean the tree is invaded and it is only a matter of time before this fungus and others, along with a host of insects, converts the tree back to the soil in which she began.

It is now three years since that first large limb broke. The tree, now almost limbless, still struggles to rejuvenate. With all but one or two large limbs lying on the ground, the remaining limbs have re-sprouted and are covered with vigorous new growth. The tree, ‘knowing’ it is in the throes of death, produced extra heavy crops of acorns several seasons ago. These acorns sprouted and now form a ‘holy’ circle around the dying oak. Without the heavy canopy of greenery to obstruct it, the sunlight pours in to aid the saplings’ growth.
This particular oak has a personal history for me. My son used to sit in a groove in one of its low-lying branches and I’d push the branch gently like a swing. As he got older he climbed on its limbs. Friends I know took pictures every year for the holidays of their children sitting on this tree. But all oaks have stories they are silent about. This oak could tell over 250 years worth of stories.

From the beginning of it’s life as an acorn until it’s demise, oaks feed and shelter an enormous variety of life. Leaves provide food for small insects such as caterpillars, leaf miners, tussock moths, aphids, mites and leafhoppers. Large mammals such as deer and wood rats browse the young tender growth. If an oak survives all the browsing, it grows up to provide shelter for a variety of birds, mammals and insects. The large canopy regulates heat, wind, light, moisture and temperature, providing animals within its branches all they need to build nests, lay eggs, and ward off predators. Reptiles—salamanders, snakes, and frogs—live in the cool leaf litter below, as well as small mammals and insects.

Oak communities in Marin also serve as corridors for birds that travel long-distances in their migrations. Many of these birds over-winter as far south as South America. Other species of birds over-winter in Marin, enjoying our mild climate. Our oak has probably seen many different species of non-native birds move through its branches, some nesting in its branches year after year before they head back to northern grounds in the summer.

The leaves, the canopy, and the leaf litter—the oak gives of itself to its ‘community’. Yet there is even more that our oak gives. The most life giving force of the oak—the acorn—is consumed by a wide array of animals. From the smallest to the largest–insects to man—the acorn provides food. Maybe this oak was standing here when black bears and grizzly’s feasted on her bounty of acorns. Maybe this was a preferred tree for the Miwok Indians that lived in these lands. Squirrels, wood rats, scrub jays and acorn woodpeckers cache nuts for the winter. Deer, pigs, and other large mammals fatten up for the winter on the oily nuts. “The list of organisms that feed on acorns is encyclopedic”, says botanist Glenn Keator.

For thousands of years life for Native Americans living in Marin revolved around the oaks. Not only did each tribelet know the location of important groves around them, but some families even had “collecting rights” to special groves. Time was measured by the oaks. The new year began with the acorn harvest, and every month was a ‘moon’ after or before it. The people followed every stage of the oak’s development throughout the year with awe and joy, from the tiny pink flowers to the gradual ripening of the acorn, when runners were sent to check on the health and abundance of the acorn crop. Excitement and anticipation swelled as fall approached, for the acorn gathering was the biggest event of the year. It was not only the annual occasion for the gathering of acorns, but a confluence of tribelets and relatives enjoying feasting, gambling, games, and socializing. In early October the tribelets made their way to the ancestral groves. Every night dancers dressed up in feathers and ceremonial paints, chanting and dancing not just to spirits or the Great Spirit, but to the trees themselves. One can imagine the oaks reveling, glowing even, with pleasure and health as the Miwoks gave their hearts and reverence to them. These trees, which spend their year giving so much, were now being given back to through the ecstasy of song and dance.

When the morning came, the entire Indian community gathered acorns. Boys climbed trees and shook the branches; men used long sticks to knock down acorns; and everyone collected acorns off the ground, tossing out the ones with wormholes. Baskets were filled and refilled. So it went day after day for almost a month—ceremonies in the evenings, gathering acorns during the day. The nights were colder now; sometimes there was rain. The Indians slowly dispersed back to their villages. Now it was time to begin the long and tedious process of leaching the tannins out of the acorn, grinding the nut into meal, and storing the meal away from animals. A typical Miwok family consumed up to 2,000 pounds of acorns a year. Although this might seem high, consider the mule deer, which can eat over 300 acorns a day in October. Acorns are highly nutritious, comparable to wheat or barley, yet with a much higher fat content—around 18% compared to 2%.

With the disappearance of the Miwoks, their culture disrupted and denigrated by the missionaries and the Spaniards, a new order emerged in Marin—the Dons or Mexican ranchers and landowners. The Mexican government granted large tracts of land to any citizen who wanted to settle in California. By the mid-1800’s, the few Miwoks that were left had congregated around the Nicasio area. Promised a large tract of land, they were subsequently cheated out of it by a greedy Don. Never having a need for the concept of land ownership, the Miwoks unknowingly signed over their land rights—and a piece of history disappeared. On that day, the oaks cried and the hills became silent forever. Unwritten histories, like footprints in the sand at the beach, show no tracks, leave no trace.

Soon thereafter, California began a series of rapid changes. We became part of the Union, but even more importantly, gold was discovered. That discovery marks a dramatic shift in the state of our eco-system and our oaks. Most redwood forests can measure their age based on the dates of the gold rush. San Francisco was a growing boomtown, where people came down from the hills to sell their gold, restock their goods, and have a good time. Timber was needed to build the cities. Where before this time all our redwood forests were old growth, now logging mills sprang up, cutting down old growth and replanting with young trees. Most protected redwood forests have trees that are no more than 100 to 150 years old—the gold rush!

Although oaks were generally spared this fate since their wood is not a straight grain, they faced other new perils. Oak country became primary cattle grazing land. With cattle came several new problems. First, the introduction of European annual grasses brought in through feed and feces all but obliterated the perennial bunch grasses that are native to California. These annual non-native grasses sprout quickly in the spring, using up precious water that would otherwise nurture young oak seedlings.

In order to protect the cattle, mountain lions were killed, dramatically reducing their population. With the big cats gone, the deer population exploded. Deer and cattle love to browse on the young leaves of oaks. Young oaks are often shrubby and bush-like because of this grazing. Once they make it past about 5 feet, they will grow into the tree structure we are familiar with. But many never make it past this point due to the continuous grazing.

Declining populations of bobcats, fox, coyotes and badgers have allowed an explosion in the rodent population. Many studies have shown that less than 1% of acorns escape rodent predation.

Cattle also compact soils, making rainfall penetration difficult. And yet cattle grazing has actually been one of the uses of open oak grasslands that have preserved our oaks. Because oaks live so long, it will be decades before the impact of cattle on grasslands can be fairly evaluated. It may be fair to say that the decline in oak seedling population is due not to cattle grazing, but to a whole range of factors, cattle grazing accounting for only a small percentage. In our changing and shrinking world, the demand for land is great. Protecting large tracts of land for parks can be difficult to politically initiate, especially within critical time frames. Oaks may actually need cattle to survive, since ranchers, working in conjunction with biologists, can help work to preserve our oaks.

One of the biggest threats to our oaks has been development. Housing and shopping malls have replaced oak lands. Children who inherit their parents ranches, yet have no need for ranching themselves, are stuck with huge inheritance tax bills and no cash to pay the government. The easiest solution is to sell the property to the highest bidders i.e. developers, and pay off the debts with the cash. Oaks don’t adjust well to grade changes, summer watering, or soil compaction. If the developers don’t bulldoze them down, usually within thirty years the old oaks have fallen down or have declined beyond saving.
The recent discovery of the deadly Phytophthora fungus is a new and interesting twist in our story.

Fires have always been a natural part of the California eco-system. Many of our native plants are adapted to fire. This means for some that their seeds will only open and sprout after the heat of a fire. For other plants it means they only establish themselves in fire stricken areas, growing quickly with nitrogen-fixing nodules in their roots that add nutrients to the new, bare soil. Oaks are highly adapted to lower temperature fires.

Higher temperature fires come about only when there is an abundance of brush to burn. This occurs usually in areas that haven’t burned for a long time. Fires were a natural part of the ecosystem in the woodland community. For millions of years, fires raged naturally every 50 to 100 years, ignited by lightning. Native Americans exploited this natural process to their advantage, practicing controlled burns. Clearing underbrush insured better hunting, easier gathering of acorns, less chance of large hot wildfires, and was even a type of ‘farming’. Since some plants grow more abundantly after a burn, the Miwoks used this principle to enhance the growth of certain seeds and forbs they desired. The land we now see was not the land encountered by the explorers. That land, over 300 years ago, was consciously shaped and altered by the Miwoks, giving it an almost park-like quality. They were the stewards of the land and their tool was fire.

Oaks have adapted for millions of years to California wildfires. Fire improves sapling growth and, most importantly I think, eliminates fungi from the soils. Remember our old oak, dying slowly, struggling to ward off fungi. Nature’s natural control for fungus is heat.
We are now facing one of the deadliest threats to our oaks, the Phytohthora fungus. Biologists around the state are trying to determine what this fungus is and how it got a foothold so quickly on our oaks.

When I began pondering ‘my’ oak, I thought of just how slowly and organically it was dying. On the other hand, oaks that are dying from the Phytophthora fungus die a quick and extreme death, one that seems almost unnatural. A rogue fungus, seemingly imported via landscape material, it moves in like an odorless, colorless, cloud of death, choking the life force of the mighty oak. The oak oozes black blood, the beetles come in and finish the tree off. Never have we seen such ‘natural’ violence done so quickly to so many of our oaks. It is as if some unknown and mighty power released its chemical weapons across our county, tumbling the oaks like dominos.

Even the appearance of their death is different. The usual slow and graceful death of most oaks imparts a kind of dignity in death that Phytophthora-infested oaks do not. The leaves on the entire tree, over the course of a few months, quickly turn a rusty brown. The tree remains standing with its leaves dried up and dead, the life oozing out of it. Suddenly its limbs begin to crack and break, and in no time at all the entire tree falls over. There is no stump sprouting, no time for a bumper crop of acorns. No fight could be waged; before the tree knew what hit it, it is dead. If there was ever a war of the vegetative world, we are witnessing it now, here in Marin.

I can’t help but think that if fires had still been regularly happening here in Marin, in California, no fungus could have gotten such a stronghold. If we humans were able to step out of this picture, fires would come again, destroying the perennial grasses and restoring our native bunchgrasses, killing the fungi in the soil, eventually putting the wrongs right. The fires at first would burn hot, for they haven’t come for hundreds of years. The hot fires would destroy some oaks, instead of aiding them. But over time, as they burned more regularly, new oaks would again spring up and the balance might be restored. Of course, we aren’t stepping out of the picture, and intelligent, informed stewardship is truly the only way of preserving our oaks for future generations. I am sure this stewardship must include fire, as the oaks have adapted to fires for millions of years. And in that adaptable is a mutual dependence—oaks must need fire in ways we humans still don’t understand fully. I believe the Phytohthora fungus is evidence of this.

There are entire ecosystems that are built around one species. Ecologists call this species—whether animal or plant—a keystone species. A keystone species is a species that is so essential to the landscape that if removed or reduced, causes a domino effect of extinctions to occur. In the South Pacific, flying foxes fill this niche. In tropical forests, figs hold the eco-fabric together. Many types of oaks are considered keystone species, binding their eco-community together. Ask any Miwok. He or she will tell you what the keystone species is here. Ask the scrub jay or the acorn woodpecker, the deer or the wood rat, the oak moth caterpillar or the tiny cynipid wasp looking to lay its egg in the tissues of the oak, whose offspring will later stimulate the oak to form a gall around it. What this entire living ‘community’ knows is no secret to the scientist as well—we are in the presence of a great and wondrous keystone species.

Oak communities have lived for thousands of years before humans entered into their fabric of existence. A kind of beauty, untouched, pervaded the land. But it was lonely and the oaks had no one to sing their praises. When the Native Americans celebrated their “giving trees” with song and dance, the oaks shimmered, as a woman shines more beautifully in the presence of her lover. The landscape was a poem unsung. The Miwoks simply gave voice to it. Since they stopped singing over 200 years ago, our oaks have been declining. It is a clear message. In essence, the Native Americans here were a keystone species as well, serving the landscape and all the creatures who depended upon these oaks.

Our job today must be to sing for the oak trees again, appreciate all their giving, infuse them with life, so we can watch them glow with health again. I can’t tell you how to do this. I believe it is a process that takes place in the heart of each individual. Yet imagine if once again, like the Miwoks of long ago, each person (or at least many, many people) began to open up and deeply contact their native and ancient feelings of reverence and appreciation of our oaks. Then and only then, I believe, will our oaks begin to glow once again.



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leslie@ecoscapes.net :: phone (415)336-3405