Parasol or umbrella?

We usually call them umbrellas, without thinking that the word umbrella means “little shade.” When parasols became fashionable among women in the nineteenth century, it was about the only way that they could find any shade. And that is because the nineteenth century was the time in which westerners cut down as many trees as possible, as if they were enemies or impediments created by God just to vex us.

Of course, trees are perhaps the ultimate blessing of creation. The photosynthesis of their leaves puts oxygen into the air, removes carbon dioxide from the air, and create cool shade. The trunks transported massive amounts of water from the soil into the air, creating clouds. The roots held the soil in place. Trees created new soil; their shed leaves were mulch, which held moisture in the soil. You can read all about it in my book Green Planet.

We take parks for granted. Of course every town has at least one. But this is a new way of thinking that westerners did not have until late in the nineteenth century, when Frederick Law Olmsted created the concept and oversaw the creation of municipal parks, starting with Central Park in New York but extending all over America. Europe did it too. As a result, it was not as important to have a parasol as it had been before; to get out of the sun, just duck into the shade of a tree. The new concept created by Olmsted has transformed our world. Think about this next time you park or walk in the shade.

More Evidence, As If We Needed It, of Global Warming, part three

I am posting this on the day on which Europe is having its warmest May on record, passing previous records by a long ways. The ways I am keeping cool is by sitting under ceiling fans and not doing much except writing. But this series of essays is not about global temperatures directly, but about their effects on the seasonal activities of plants.

I conducted a sixteen-year study of budburst dates in Oklahoma deciduous trees, and I found that winter buds opened in spring earlier and earlier each year, consistent with global warming. The results were highly significant. I did not, however, have time to publish this study in a scientific journal before I retired. I decided instead to publish it on my website. Here is the link to the article, with illustrations. Please note that the mailing address on the cover page is now obsolete; you may contact me through the website email link (stanriceauthor@gmail.com).

I here address an interesting point about this research, aside from its unsurprising conclusion. And that point is, how do we avoid bias?

Here is a photo of mulberry buds.

Everyone is biased, including scientists. The people who proclaim themselves to be unbiased (politicians, industry leaders) are in fact the most biased people in the world. Scientists are much less biased, and for good reason. The process of scientific research requires specific steps to be taken to deliberately avoid bias. So, when I conclude that global warming is occurring, a politician (such as the infamous Oklahoma Senator Jim Inhofe, who said whatever oil companies paid him to say) could accuse me of being biased. This is true, but I, unlike him, deliberately designed my research to minimize the bias. Take that, Jim Inhofe! I cannot tell him this, because he died in 2024.

Here is how I did it. For sixteen years, I walked around and noted the budburst dates of a couple of hundred trees. In the back of my mind, I was thinking that the sixteenth year would have much earlier budburst dates than the first year. That, of course, is bias. But budburst is a continuous process. If you note down the very earliest date on which the buds appear to reawaken in the spring, you get an early budburst date; if you note down the first date that the leaves or flowers emerge from the bud, you get a medium budburst date; if you note down the date on which the leaves or flowers are fully expanded, you get a late budburst date. I had to choose some indicator of budburst; I chose the date on which the bud swelled just enough to allow the tissues inside the bud to be visible. And once I had chosen this indicator, I had to stick with it for sixteen years. You can see this in the color photos I included in the article, and in these blog essays.

The technical term for choosing a standard of measurement is construct validity. You can read about it in my book about the adventure of scientific discovery.

There is, in addition, a tradeoff between how detailed your observation can be and how many observations you can make. You cannot measure everything everywhere. When it comes to spring budburst studies, they fall into two categories:

First, satellite measurements. Satellites can measure buds turning green in the spring over hundreds of square miles. This allows the results, such as earlier budburst, in any one location to be generalizable over a larger area. This gives satellite measurements external validity, that is, they are valid not just for the area in which the measurements were made.

Second, there are ground-based studies, such as mine. I am sure of the budburst date and species for each tree. But, as I openly admit in my article, the external validity of ground based studies is limited.

I will explain, in the next essay, yet one more interesting point about scientific research into global warming.

Forgotten Landscapes: Native Americans and Cool Shade

I have just published my sixth book, Forgotten Landscapes: How Native Americans Created Pre-Columbian North America and What We Can Learn from It. I am starting a series of essays and videos to promote portions of this book. The video that goes along with this essay is here.

In this book, I describe one ecological problem that white European and American villages had that Cherokee and other Native villages did not was the problem of how to stay cool in the summer.

The video shows my neighborhood in Alsace, France. It is densely populated, and there are hundreds of condominiums right next to my building. Our condominiums are very energy-efficient, even the ones built a long time ago, such as mine. Our windows and walls are thick, which keeps our units quiet as well as insulated. And this is how that efficiency is achieved:

• Sources of energy. Instead of each condominium having its own individual heating units, as is often the case in America, these buildings get their heat from hot water going through radiators. The hot water comes from a network from a centralized power plant where furnaces burn methane to heat the water. The methane (as I described in the previous video) comes partly from food wastes.
• Required energy efficiency. Whenever one of the condominiums is sold, the building owner has to meet new standards of energy efficiency, e.g. through improvement of insulation; the building owners pass the costs to condo owners who pass the costs on to renters.
• Little but deliberate things. In the middle of our courtyard there are a lot of trees, which provide cool shade. There are two reasons for this. First, the leaves absorb sunlight energy and emit the heat straight up into the air, away from where we live. Second, transpiration (the evaporation of water) uses up some of the heat energy. These îlots fraîcheurs (cool islands) are a deliberate part of urban planning. Some American cities do this also. Las Vegas recently decided to plant trees to help deal with the over-110-degree summer heat. The problem is, where are they going to get the water for the trees? It can be done, but has to be planned.
• Air conditioning. Very few French apartments have air conditioners. We are just lucky to live 48 degrees north latitude where we can get away with not having air conditioners.

In my book I describe Cherokee villages that were filled with trees that kept them cool. Meanwhile, white cities would, at the time, cut down all the trees. The Cherokees were probably puzzled that white people would work so hard to cut down the trees and then get, literally, hot under the collar about the summer heat.

I doubt that the Native Americans knew more ecology than white Americans. They just thought cutting the trees down was a lot of hard work with nothing to show for it.

 

Greetings. I have a felicitous essay with which you can begin your new year.

I have just finished the manuscript of a seventh book that I hope to publish next year (2026), if I find a publisher this year (2025). This is in addition to my sixth book, Forgotten Landscapes, which is scheduled for release July 2025. But right now I want to tell you a little about the seventh book, Every Plant Has a Story.

There are lots of books about botany for the general reader. But almost all of them are about why humans should appreciate plants, e.g., they are sources of food, spices, hallucinogens, etc. That is, plants as slaves of humans. But my book is about the stories the plants tell about themselves, as discovered by scientific research. I will not attempt to summarize it here, but will probably do so a bit at a time in the essays I will post in the coming year.

Every plant has a different story of success in the ruthless Darwinian world of competition. One example is that some plants grow as long-lived trees, while others are short-lived weeds. The long-lived trees (like oak trees) invest a lot of time and energy in building up for the future. They are tremendously successful, but it takes centuries for them to earn back the costs that it took them to build themselves. They epitomize long-term investment. Weeds, on the other hand, do not have a long term. They grow like crazy for, in most cases, a single year, then pour all their resources into seed production. There are all stages in between, such as short-lived trees (like cottonwoods).

Above: sequoia trees invest for long-term success, over millennia; below, weeds such as velvetleaf invest for success only one year into the future, then they die.

Weeds specialize on temporary habitats, such as an area disturbed by fire, flood, or human activity. Trees specialize on habitats that remain stable for many decades, even centuries. Since the Earth contains both kinds of habitats, stable and temporary, the weed approach to investing and the tree approach are both successful, in different places.

The analogy with the human economy is inescapable. You can either invest for the long term, building up savings and assets, preparing for the future. You can manage your life like a tree. Or you can spend quickly and go into debt, as if you have no future. You can be a weed. It is the people who live like trees who make the world a better place, who stabilize it. But there are plenty of people who live like weeds also.

Humans are, however, changing the global climate. Not just heating it up, through the greenhouse effect, but creating a climate that is wildly catastrophic—fires, hurricanes, floods, and all the rest. The entire world now has or will soon have an unstable climate, everywhere. Plants that make long-term investments, such as trees, may not live long enough to be successful. Only weeds, which often live just a year, can survive in a world where the climate changes rapidly. No longer will tree investments and weed investments both be successful at different times and places. Now only the weeds will succeed. I summarize this situation in the last chapter of my book: Trees are out, weeds are in.

Trees are out, weeds are in. This means that if you expect to see old forests with big trees, you’d better see them right away. And then prepare to live in a world in which there are no plants except those that grow and die rapidly. Someday, the giant sequoia forests of California, where huge trees live for millennia, will be regarded as part of a mythological past.

The analogy with human investments is again inescapable. Long-term investments, in which a corporation plans to be a stable force for good over many decades, are on their way out. Short-term investments, to make a killing rather than a living, will soon dominate the economy of the world. Only the long term allows a corporation to invest in reputation: we are a company you can trust for life, we want you to like us. Instead, corporations will all be rewarded for being rapacious, treating their customers like garbage, and they don’t care who knows it. Yes, we dump our wastes into the common space in which we all live; yes, we deny your insurance claims; no, you cannot expect us to actually honor our contracts.  In a truly free economy, consumers can choose to stay away from dishonest corporations. But in many cases, when a corporation treats its customers like garbage, and it starts to collapse, the government will come in and rescue it, or else it will merge with another corporation. Corporations lose their recognizable identities, so you cannot choose to stay away from them. The future of the human world, as of the natural world, will be wildly swerving among disasters, in which you cannot responsibly plan ahead.

I have been reading Naomi Klein’s 2014 This Changes Everything. She makes it abundantly clear that our world economy cannot possibly avoid climate-related collapse. Any company, or country, that invests in the future rather than in immediate profitability is swept aside. Countries, companies, and individuals who choose sustainability are usually beaten down. Unless solar energy is, without subsidies, cheaper than government-subsidized fossil fuel energy, it will be driven into extinction. The time is coming, soon, when sustainability will be essentially illegal. By choosing to spend less money, I am making myself an enemy of the consumerist economy. I am basing this view on Klein’s 2014 numbers. It is much worse today.

I was expecting that my seventh book would be a cheerful celebration of the diversity of plant adaptations even to the most challenging environments. I did not plan for it to be an activist book. The time is past when I delude myself into thinking that any book I could possibly write would change the views of any readers who did not already agree with me. But, despite my plans, my seventh book has become an activist book, a voice of a prophet in the wilderness, from what the short-horizon leaders of the world economy think of as the extreme left.

This represents an almost complete departure from everything I wrote in previous years. Before, I was hoping to help change the world. Now, I just want those of you who care about the long-term well-being of humankind to feel a little better about the way you are living.

Trees are out; weeds are in. Happy New Year.

The Importance of Urban Trees

 

I have always (even when I was a child) been inspired by trees out in the forest, especially the giant sequoia trees in the Sierra Nevada mountains near the town where I grew up. In contrast, urban trees seemed much less important, especially since many of them are horticulturally altered versions of tree species that are not native to the area. Urban parks and woodlots offer shade and peace in cities, but compared to the canyonlike buildings around them, they seem to be of little importance. A park cannot compare with the grandeur of a forest.

I just finished reading a book by Thomas Brail, The Man who Saved the Trees (L’Homme qui sauvait les arbres; Arthaud 2022). He became alarmed at the many thousands of trees (mostly planes, which we call sycamores) that were being chopped down in cities all across France. He is an expert tree climber, part of his work as an arborist. He climbed into a sycamore tree in Paris, right across from the office of the Ministry of Ecological Transition, which was one of many trees slated to be cut down. (Can you imagine such a department in American government?) He stayed there for 28 days, until the Ministry decided to reconsider whether to save the trees. He admitted that, sometimes, it is necessary to cut down a tree, but many urban trees were being cut down to widen sidewalks and make them sunny. But during hot weather, direct sun is not something you want. And the trees provided many other ecological services to the city and its people and its ecosystems.

Brail correctly gambled that no government agency would cut down a tree that had someone in it; and there would be no point in cutting down the other trees, since the one remaining tree would be in the way of “development.” What he did not count on was how many supporters he got, from social media and from news coverage: sometimes sixty people would gather under his tree, and there were thousands of supporters around France. He even got a visit from the most famous French actress, Juliette Binoche.

But why urban trees? Is it not more important to save forests? Many oak and beech woodlands are still being cut down to make way for conifer plantations. This is what I thought until I put myself inside the mind of Thomas Brail.

It is true that a forest is more ecologically significant than a park. But on a tree-by-tree basis, the urban forest (the park) is more important. Urban trees provide benefits otherwise almost absent from the cities, and offer them directly to more people. It is not just how much oxygen they produce, or how much carbon dioxide they absorb, but where they are doing it. Having one less tree in a forest might not have as much impact as having one less tree shading a sidewalk.

And urban trees keep the natural world squarely in the field of attention of people who might not otherwise give a thought to the natural world. My thought is that urban trees are the missionaries of the tree world into the artificial human world.

Thomas Brail does not live in trees anymore. Nor does he say you have to. What he does and wants you to do is to eat less processed food, and more food from a garden; and to get rid of television, while instead looking for inspiration in the world of Nature. Perhaps most importantly in his work, he remains calm in the face of confrontation. He wants the forces of destruction to be the ones to get angry, thus making them seem to be stupid (ils ont l’air idiot).