The Thinking, Walking Biped, part fourteen. Dreamscapes

When we walk, we each see our world in a different way, and differently at each stage of our lives. Let me tell you a personal example of this.

I grew up at the base of the foothills of the Sierra Nevada mountains in California. I could see the snow-covered peaks of the mountains in the clear air of winter, and I occasionally visited the magnificent forests of giant sequoia trees. But what I saw every day was the foothills. They were covered with grass. The only trees were oaks that grew amidst granite boulders on some of the hills. I am still not sure why the trees grew only amidst the boulders. Perhaps it was fire, or perhaps it was cattle, both of which could kill trees on smooth ground. But even on the smooth ground, there were occasional boulders, some of them large and craggy. They reminded my childish mind of menhirs and dolmans and other works of human art.

Boulders on smooth hills made me feel like I was looking at a heavenly landscape. Even today I have occasional dreams of entering an enchanted realm of boulders and grass. These are almost the only really beautiful dreams I have. Thankfully, I don’t have many nightmares. Most of my dreams are busy and stupid and quickly and thankfully forgotten.

The magical landscape of boulders and grass is not the real landscape. The weeds amidst the grass, such as fiddlehead Amsinckia, and even the grass itself, especially the wild oats Avena barbata, left prickles in my socks. Most of the year, all the plants had died back to the ground. Everywhere was the scent of cow dung. That is the reality. But that is not what I dream.

To get to the biological field station where I taught botany one summer, I drove through northeastern Kansas. There are interesting parts of Kansas, but this was not one of them. It was absolutely flat and often nothing but wheat fields was visible. Fortunately I had not passed judgment on this land, for it is where one of my students was from. “It is the most beautiful place on Earth,” she said. And she was right, about her dreamscape.

This sort of dreamscape is not reality, nor is it illusion. It is a transformed reality. I wonder if any other species of animal has this kind of imagination. And I wonder how much it is the product of our long history, and much longer prehistory, of long distance walking, of tribal leaders imagining themselves on the top of a distant mountain.

My Green, Green Happy Place

Sometimes I like to go to my happy place. This time, it was so that I could relax and enjoy my happiness at being a new grandfather. For some people, their happy place is a fantasy inside their minds. But for me, it is an actual place: the forest. In particular, the forest on Turkey Mountain outside of Tulsa.

The forest is a place with layers upon layers of stories. It is a palimpsest, that is, a document with layer upon layer of writing. On this particular like, I already knew almost all of the stories. One story was the geological history of the landscape. As I looked down from the mountain onto the Arkansas River, I remembered that this mile-wide river was once ten miles wide, as the glaciers up north melted. Another story was about human impact. The forest all around me grew in just the last century, since the time when this mountain was covered with oil derricks. Each species of tree, and each tree, had its own story: an evolutionary story of adaptation, and a developmental story of how each individual tree adjusted to its immediate environment of shade and sun, of deep soil or rock outcrop. The story is written from moment to moment. When I hiked, a drought was underway, and many leaves were wilted. Wilting is not completely a bad thing; by drooping down, a leaf has less of a heat load from the sunlight and avoids some of the damage it would otherwise experience. There are also many stories of food webs, whether it is of insects that have eaten the tender leaf tissue between the veins, or fungi eating dead branches. There is the story of the hard, green, inedible persimmon fruits that keep animals away until the seeds are ready to disperse, and only then do the fruits become ripe and delicious. There is the story of stumps sprouting back to life.

I knew all of these stories, but I just wanted to see them again on this hike. But I kept my eyes open, just in case there was a new story. And I found one—just one. A mimosa sampling was hit hard by the drought. Mimosas have lots of little leaflets which, after being held horizontally to face the sunlight in the day, close upward at night for reasons that nobody knows for sure. The leaflets also close upward during moderate drought, thus reducing their solar heat load. The leaflet movements are caused by bags of water called pulvini (singular pulvinus). When the bags of water exert pressure, they push the leaflets; when the bags lose pressure, the leaflets return to their original position.

But what I did not know was, are the pulvini on the top of the leaf or the bottom? If they are on top, then the water pressure pushes the leaflets open; their nocturnal closure represents only a loss of pressure, a relaxation, going to sleep. If this is the case, then the closure of the leaflets at night does not need an explanation. The plant is saving energy by letting the leaves relax. But if the pulvini are on the bottom, then the nocturnal closure demands an explanation: why would the mimosa leaf deliberately close its leaflets at night? This requires the expenditure of energy. The same is true for leaflet closure during moderate drought. If the pulvini are on the top, leaflet closure is merely the result of drought; but if they are on the bottom, then leaflet closure is a deliberate act to prevent drought damage. Of course, the pulvini are too small for me to see.

But I saw one leaf that was so stressed by heat and drought that the leaflets were starting to curl up and die. And in this leaf, the leaflets were horizontal. This tells me that the pulvini are on the bottom. I know this because, when severe drought causes the pulvini to stop working, the leaflets are horizontal, not vertical. In the photo, the drought-damaged leaflets are on top, the leaflets that are actively responding to drought are on the bottom. The damanged leaflets are horizontal, and the responsive leaflets are almost vertical.

To me, this was a new story that I learned on my hike. But I enjoyed re-experiencing the thousand other stories in the forest that I already knew.

A Landscape Thick with Stories

Every landscape is a palimpsest thick with stories. Where I live in Oklahoma is an example.

First, there is the story of its evolutionary past, for example when the part of Oklahoma in which I live was the bottom of a shallow sea, creating limestone filled with seashells, or when the Ice Ages caused Oklahoma to be cold and dry, a place where spruce trees and mastodons lived.

Second, there are the primordial human effects just after the most recent Ice Age. The native peoples who originally lived here were hunters and gatherers, but they deliberately manipulated the environment. They often set fires, which cleared away some of the forests and created grasslands on which game animals could graze and browse. The post oak forests were open and light because the fires did not often kill the large trees, and the oak seedlings could resprout.

Third, there are the secondary human effects caused by later immigrants, not only whites but the Cherokees, Chickasaws, Choctaws, Muskogees, and Seminoles, and later by dozens of other tribes. Not only the whites but the “Five Nations” of natives displaced from the east brought agriculture and ranching.

Finally, there are the modern effects caused by the exploitative human economy: urbanization, pollution (especially from oil extraction), and global warming.

When I walk or drive through Oklahoma, I think about all of these layers of natural and human effects on the landscape. I see myself as part of that last layer (I hope a less destructive member of that layer than are many other people), and therefore as part of a complex set of stories.

In contrast, when someone drives a big truck as fast as possible, spewing black smoke from the tailpipes, they are experiencing only one story: “me, me, me, me.”

Another place that is a palimpsest of stories is central California, where I will be going to my fortieth high school class reunion tomorrow. The San Joaquin Valley was once a vast marsh teeming with wildlife, with water coming into it from snowmelt through the Kings, Kaweah, and Tule Rivers. Today nearly all of this water has been diverted into agricultural irrigation and (to a lesser extent) domestic use.

The landscape has been totally altered into agricultural fields and weed patches, with just a few exceptions. When I grew up there, I thought I was lucky to live out in the countryside, away from the air pollution of Los Angeles. But today, and even back then, the air quality of the Visalia-Tulare-Porterville area is one of the worst in the nation, and the environment was (is?) permeated by pesticides. The story of human alteration and pollution of the land overlies the natural environment. And part of the human story includes economic injustice: migrant farm workers barely make a living, in that pesticide-drenched land, on vast farms owned by rich corporations.

We need to be able to read the palimpsest of stories on the landscape in order to understand the Earth on which we live and which is endangered by our activities.