Hilary's Book Blog

I liked this very much – some Nature and Environment folks thought it wasn’t human-focused enough, but that’s what I enjoyed. Dunn outlines what he calls “life’s laws,” principles akin to gravity, inertia, and entropy, that affect our environment but which humans mostly ignore at their peril. I didn’t make a proper note of them all as I read, so this list may be incomplete.

• Species-area law (from island studies: how many species will emerge in a given geographic area)
• Natural selection (evolution away from any imposed control like pesticides etc.)
• Law of the niche (limits how much species can adapt to climate change, for example)
• Law of escape (species moving away from their natural controls)
• Law of dependence (we need our microbiome, for example; moving to outer space or other planets is a fantasy)
• Law of cognitive buffering (species with extra brainpower will be adaptable to more conditions)

I would love to go back to this book someday to re-order/check this list – and read/re-read Dunn’s other books, because I love his writing style. He is both witty and inspiring. We had previously read Never Home Alone, which was also great, and there are many others.

In this book I learned

Although with a book like this, it’s a fine line between this section and the short quotes – those should also be memorably expressed, which for someone like Dunn makes the line even finer!

• In Panama, Terry Erwin found about 1,200 different beetles, “more beetle species in one kind of tree in one forest than there are bird species in the United States”
• There’s microbial life – lots of it – in the Earth’s crust! (Dunn doesn’t mention this, but looking this up taught me of the boundary called “the Moho” – great name)
• Culex pipiens mosquitos populated the London Underground in the 1860s and are now a variant or possibly a new species, Culex molestus
• A population of Aedes aegypti mosquitos, who can’t survive the cold outdoors in DC, persist by using human structures under the Mall in the winter
• Humans mostly still live in the temperate areas of the globe; there are more of us but we’re just more concentrated in the same comfortable-for-us places, not spread out
• “House sparrows can think circles around other species of sparrows”!
• “It is thought that the ability and need to pass along microbes was part of what made termites social”
• C-section babies miss being exposed to their mother’s microbes (increased risk of diverse diseases & infections)
• Dallol geothermal area – amazing images – populated by Archaeans whose “dozen species are more evolutionarily diverse than all the vertebrates on Earth combined”
• “Coendangered” (now “coextinct”) species like the black-footed ferret louse and the California condor mite
• “Colonies of a single species of army ant, … Eciton burchellii, host more than three hundred other species of animals (to say nothing of other life-forms, such as bacteria or viruses)”

Short quotes

• “More than half the Earth is now covered by ecosystems we have created—cities, farm fields, waste-treatment plants. We now, meanwhile, control, directly and incompetently, many of the most important ecological processes on Earth. Humans now eat half of all the net primary productivity, the green life that grows, on Earth.”
• Dunn suggests this daily affirmation: “I am large in a world of small species. I am multicellular in a world of single-celled species. I have bones in a world of boneless species. I am named in a world of nameless species. Most of what is knowable is not yet known.”
• “We are reminded of the scale of the unknown by near tragedy and actual tragedy. We forget about the unknown in the calm wake of near tragedy and the sorrowful quiet of real tragedy. We forget at our own expense.”
• “As an ecologist, it seems unlikely to me that we could engineer entirely new ecosystems on other planets that we could manage sustainably when we have struggled to avoid destroying the already functioning ecosystems around us on Earth.” [see also quote below]
• “’Variability’ sounds both vague and harmless. It is neither; it is, instead, one of nature’s greatest dangers, an elemental threat. Variability is to be feared. Variability needs to be planned for.”
• “From the perspective of their microbes … termites offer housing and transport and a bit of food preparation to boot. They are an entomological mix between a taco truck and a bed-and-breakfast.”
• “Even in those cases in which the most economical (by any measure) solution is to replace a functioning natural ecosystem with technology, doing so tends to yield replicas of those natural systems that are missing parts and, more generally, act ‘like’ nature systems but not as natural systems.”
• “Honey bees are no more native to North America than are starlings, house sparrows, or kudzu. Yet as agriculture in North America intensified, honey bees became a key piece of glue necessary to hold together a broken agricultural system.”
• “To bees, flowers are like toilet seats. And while bees do wash their hands (or, rather, their feet), that is often not enough to prevent the spread of parasites.”
• “Nearly the entirety of the living world bears the print of human biocides. We have pressed our wide thumb ever more forcefully into the spinning clay of nature.”
• “Generally speaking, it seems that the more extreme a set of conditions, from a human perspective, the less well the ant species living in those conditions are likely to have been studied.”
• “The feral cats of Australia are likely to survive the extinction of human Australians. Goats will live on in many regions. With regard to the extinction of humans, goats are tougher than cockroaches.”
• About speculation that a form of artificial intelligence could outlive us: “it is interesting that in some ways we find it easier to posit that we can invent another entity that can live sustainably than to imagine that we can do so ourselves.”

Long quotes

Repeatedly scientists have announced the end (or near end) of science, the discovery of new species, or the discovery of life’s extremes. Usually, in doing so, they position themselves as having been key to putting the final pieces in place. “Finally, now that I am done, we are done. Look what I know!” And repeatedly, after such announcements, new discoveries have revealed life to be far grander and more poorly studied than had been imagined. Erwin’s law [named after a beetle biologist] reflects the reality that most of life is not yet named, much less studied.

Trying to control the cassava mealybug:

To find the enemies of the mealybug, one would have to know where the mealybug came from. No one did. In the absence of knowing where the mealybug was from, one could benefit from knowing where the relatives of the mealybug were from. No one knew which species it was related to, much less where they lived. In the absence of knowing where its relatives were from, one might go to the place where cassava was first domesticated (where its pests and parasites and their pests and parasites might be most common). No one had studied the geographic origin of cassava in much detail.

As much as the world can sometimes seem futuristic, many of the most brutal tasks are still carried out by human bodies. Human bodies pick fruit, load trucks, and kill pigs and chickens, and so it is still human bodies on which the global economy depends. Fifty percent of global agricultural production alone depends on the work of small landholders, who do much of their work outdoors by hand. Collectively, those human bodies, with their innumerable arms and legs, are directly susceptible to the effects of temperature.

[The basic idea of the law of cognitive buffering] is that animals with big brains are able to use their intelligence in inventive ways so as to find food even when food is scarce and maybe also warmth when it is cold and shade when it is hot. They buffer bad conditions with big brains. Superficially this would appear to be a law that bodes well for us humans. We have very big brains relative to our bodies, big enough that our heads nod with their own weight when we are exhausted. What’s more, those big brains are thought to have evolved, in part, to help cope with variable climates. But whether our big brains will help us in the future is going to depend on just how we use them, whether we and our institutions are more like a crow or more like the dusky seaside sparrow [which went extinct].

Carpenter ants, for instance, depend on bacteria passed by mothers to daughters, generation after generation, in order to produce some of the vitamins they require. At least one of those bacteria species is now housed, by the carpenter ants, in a special kind of cell that lines its gut. It is inside the ant’s cells, integrated into its body. It is inherited by baby ants inside their eggs. It is part of the ant’s body, part of its egg, and yet it is still separate. Conditions too warm for the bacteria, but not the ant, kill the bacteria. Then after a while, no longer whole, the ants slowly die too.

[Space colonization would be], for humanity, something akin to a rebirth, or at least a molt. By this I mean that they require us to take with us the species we need to survive. This is a much harder task than any that species on Earth must engage in. When a leaf-cutter ant queen flies to start a new colony, she carries with her the fungus that her progeny will grow on the leaves they gather. But she doesn’t need to take with her the plants that make the leaves. We will need to take the plants and also much more.

Of the ideas I’ve articulated in this book, the idea that we should save the services of nature, where we can, rather than trying to reinvent them is perhaps both the most obvious and the most contentious. It is obvious in that on some level it is intuitive that we should not break what is already working. It is contentious in that, increasingly, the future being imagined by scientists and engineers is one in which more and more of nature’s services are replaced by technologies. Recently, a number of researchers have gone so far as to suggest that they don’t need nature. They argue that, with genes in the lab, they can create whatever is needed. It is possible that they are right. I doubt it. I suspect my vacuum-cleaner repair person would doubt it too. And here is the thing: if they are wrong, and we have failed to save the ecosystems we needed, failed to keep them from breaking, well, then the consequences will be great.

[This] shows a version of the big evolutionary tree of life. If the branches were all labeled, you would quickly notice that the names on the branches are mostly unfamiliar. Some of the big branches on the tree of life, for example, include the Micrarchaeota, the Wirthbacteria, the Firmicutes, the Chloroflexi, or the even more cryptic “RBX1,” Lokiarchaeota and Thorarchaeota. If you were to look for the branch that includes humans, you might struggle to find it. This isn’t a mistake but, rather, a reflection of our own place in life’s bigger picture.
On this tree, or rather, a sort of bush, each line represents a major lineage of life. All species with cells with nuclei are part of the Eukaryotes, represented as a single broom-like branch … in the lower right-hand section of the tree. Eukaryotes include malaria parasites, algae, plants, and animals, among other life-forms. The Opisthokonta, one small part of the Eukaryote branch, is the branch that includes animals and fungi. Animals, if we zero in, are just one slender branch of the Opisthokonta. From this broad perspective, vertebrates do not get a special branch on the tree. The vertebrates are a small bud. The mammals are a cell in that bud. Humanity is, to continue the metaphor, something less than a cell.

Ecologists love to go to and study rain forests, ancient grasslands, and islands. They hate to work in toxic dumps and nuclear sites, even if the dumps and nuclear sites are proximate and relatively easy to study. And who can blame them? Meanwhile, the most extreme deserts on Earth are both remote and inhospitable, the kinds of places one is exiled to rather than the kinds of places to which one flocks when classes are done. They too are rarely studied. The result is that we tend to be blind to the ecology of some of the most rapidly growing ecosystems, blind to the future’s extremes.

I rarely buy new books these days, but I got myself a copy, as I had done for Braiding Sweetgrass (2013). When we read Braiding Sweetgrass in the Nature & Environment book group, Robin Wall Kimmerer immediately became one of my favorite authors ever, so choosing her first book as a selection was easy. We have read a lot of single-organism books (ants, beavers, coyotes, octopuses, rattlesnakes, ravens, trees…) but this was one of the best, and features in embryo many of the themes woven through Braiding Sweetgrass. The chapters can also be treated like free-standing essays – “The Owner” stood out in particular: a truly compelling essay, more of a short story, with a twist ending – a horror story, really, both beautiful and heart-rending.

Short quotes

• “Mosses have a covenant with change; their destiny is linked to the vagaries of rain. They shrink and shrivel while carefully laying the groundwork of their own renewal. They give me faith.”
• “Mosses engineer the movement of water simply by harnessing the attraction of water for surfaces. Their forms take advantage of the adhesive and cohesive forces of water, to move the water at will over their surfaces, without expending any energy of their own.”
• “‘If you’re going to have livestock, you’re going to have deadstock.'”
• “I think we need a new aesthetic that honors a mossy roof as a status symbol of how responsibly the homeowner behaves in maintaining the ecosystem. The greener the better. Neighbors would look askance at the owner of a roof scraped bare of friendly moss.” I love the idea… but mosses surely do damage roofs simply by keeping water in touch with the roof for longer?
• “In the alveoli, your breath is but a single cell away from your blood. The cells are glistening and wet, so that the oxygen may dissolve and pass over. Through this thin watery film, deep in the lungs, our bodies become continuous with the atmosphere. For better and for worse.” Like mosses, which is why they are good indicator species of air quality.
• “The average person knows the name of less than a dozen plants, and this includes such categories as ‘Christmas Tree.’ Losing their names is a step in losing respect. Knowing their names is the first step in regaining our connection.”
• “Every way of knowing has its own strengths and weaknesses.”
• “There is more living carbon in Sphagnum moss than in any other single genus on the planet.”
• “This global cloud of spores powders every surface with the possibility of mosses.”
• “It was not money that the rocks required, it was time. And the ‘time is money’ equation doesn’t work in reverse.”
• “Wildness cannot be collected and still remain wild. Its nature is lost the moment it is separated from its origins. By the very act of owning, the thing becomes an object, no longer itself.”
• “I think you cannot own a thing and love it at the same time. Owning diminishes the innate sovereignty of a thing, enriching the possessor and reducing the possessed.”
• “trees alone don’t make a forest”
• After discussing slug feces: “biologists may make unsuitable dinner conversation, but we are seldom bored”
• her daughters “ate up the summer in heaping spoonfuls like homemade peach ice cream”

Long quotes

Day by day, [students’] vocabulary stretches and they proudly refer to leafy green shoots as “gametophytes” and the little brown thingamajigs on top of the moss are dutifully referred to as “sporophytes.” The upright, tufted mosses become “acrocarps,” the horizontal fronds are “pleurocarps.” Having words for these forms makes the differences between them so much more obvious. With words at your disposal, you can see more clearly. Finding the words is another step in learning to see.

Initial research on Tetraphis shed no light on why some patches produced spores and others gemmae:

There seemed to be no rhyme nor reason to Tetraphis‘ reproductive choice. But if there’s anything that I’ve learned from the woods, it’s that there is no pattern without a meaning. To find it, I needed to try and see like a moss and not like a human.

In traditional indigenous communities, learning takes a form very different from that in the American public education system. Children learn by watching, by listening, and by experience. They are expected
to learn from all members of the community, human and non. To ask a direct question is often considered rude. Knowledge cannot be taken, it must instead be given. Knowledge is bestowed by a teacher only when the student is ready to receive it. Much learning takes place by patient observation, discerning pattern and its meaning by experience. It is understood that there are many versions of truth, and that each reality may be true for each teller. It’s important to understand the perspective of each source of knowledge. The scientific method I was taught in school is like asking a direct question, disrespectfully demanding knowledge rather than waiting for it to be revealed. From Tetraphis, I began to understand how to learn differently, to let the mosses tell their story, rather than wring it from them.

Mosses don’t speak our language, they don’t experience the world the way we do. So in order to learn from them I chose to adopt a different pace, an experiment that would take years, not months. To me, a good experiment is like a good conversation. Each listener creates an opening for the other’s story to be told. So, to learn about how Tetraphis makes reproductive choices, I tried to listen to its story. I had understood Tetraphis colonies from the human perspective, as clumps in various stages of reproduction. And I had learned little by doing so. Rather than looking at the clump as an entity, I had to recognize that the clump was simply an arbitrary unit that was convenient for me, but had little meaning for the moss. Mosses experience the world as individual stems and to understand their lives I needed to make my observations at the same scale.

Driving the Adirondack roads, past glittering lakes and deep woods, you’ll scarcely ever see roadside litter. People love this wild place and the care for its well-being is obvious. But where Route 3 cuts through the mined land, plastic bags are caught in the alders and beer cans float in the ditches full of rusty water. Disregard is also a positive feedback loop; garbage attracts garbage.

The city mosses have much in common with their urban human counterparts; they are diverse, adaptable, stress-tolerant, resistant to pollution, and thrive on crowded conditions. They are also well traveled.

A city offers mosses a multitude of habitats which may otherwise be quite uncommon in nature. Some moss species are far more abundant in the human-made environment than they are in the wild. Grimmia
doesn’t discriminate between a granite crag in the White Mountains and a granite obelisk on Boston Common. Limestone cliffs are not abundant in nature, but there’s one on every Chicago street corner and
mosses perch contentedly on its pillars and cornices. Statues provide all kinds of water-holding niches where mosses abound. Next time you walk through the park, look in the folds of the flowing coat of whatever general sits mounted on a pedestal, or in the wavy marble locks of Justice’s hair outside the courthouse. Mosses bathe at the edges of our fountains and trace the letters on our gravestones.

…

We tend to devalue the flora of cities as a depauperate collection of stragglers, arising de novo with the relatively recent development of cities. In fact, the urban cliff hypothesis suggests that the association between humans and these species may be ancient, dating from our pre-Neanderthal days when we both took refuge in cave and cliff dwellings.

I take great pleasure in gathering plants, filling my basket with roots and leaves. Usually I go with a specific plant in mind, when it’s time for elderberries or the bergamot is heavy with oils. But it’s the wandering itself that has such appeal, the unexpected discoveries while looking for something else. I get the same feeling in the library. It’s so very much like picking berries—the peaceful field of books, the concentrated attention of the search, and the knowledge that hidden somewhere in the thicket is something worth finding.

Its tremendous water-holding capacity allows Sphagnum to modify the ecosystem for its own purpose. The presence of Sphagnum causes the soil to become saturated, filling the spaces between soil particles that might otherwise hold air. Roots need to breathe, too, and the waterlogged peat creates an anaerobic rooting environment which most plants can’t tolerate. This impedes the growth of trees, leaving the bog sunny and open.

[The hairpiece’s] intricate design of bees and flowers was carved from luminous ivory. I was immediately struck by how out of place it seemed on its velvet platform, more like a stolen treasure than a work
of art. How much more beautiful it would have been in the black oiled hair of the artist’s wife. And more authentic. In a display case, a thing becomes only a facsimile of itself, like the drum hung on the gallery
wall. A drum becomes authentic when human hand meets wood and hide. Only then do they fulfill its intention.

At the center of the garden stood a sculptured rock taller than either of us and beautifully covered with mosses. Each carefully chosen clump accented the irregularities of the boulder. An eroded pocket in the rock was filled with a perfect circlet of Bryum. The artistry rivaled any piece we had seen in the gallery and yet it struck the wrong note; the collection was only an illusion of nature. Plagiothecium can’t grow in crevices like that, and Racomitrium wouldn’t share a habitat with Anomodon, despite the beauty
of their colors side by side. I wondered how this beautiful but synthetic creation passed the owner’s standard of authenticity. The mosses had been reduced from living things to mere art materials, ill used. “How did you get these to grow like this?” I asked. “It’s very—unusual,” I hedged. Matt smiled like a kid who had outsmarted his teacher and answered, “Superglue.”

Mosses have an intense bond to their places that few contemporary humans can understand. They
must be born in a place to flourish there. Their lives are supported by the influences of previous generations of lichens and mosses, who made the rock into home. In that initial settling of spores they make their choice and stick to it. Relocation is not for them.

Here on the shadowy edge of where green life seems barely possible, Schistostega has all it needs. Rain on the outside, fire on the inside. I feel a kinship with this being whose cold light is so different from my own. It asks very little from the world and yet glitters in response. I have been blessed by the companionship of good teachers and I count Schistostega among them.

In this book I learned

• Boundary layer where moss lives: more heat, water, carbon dioxide (10x!), less turbulence
• Gemmae cups on moss – little eggs that are clonal propagules! They don’t go far – they “carry a combination of genes that has already proven successful on this stump,” whereas spores are “a powder of potential sent off to seek its fortune in the unknown realm beyond the stump.”
• Psychrometer – wet-and-dry bulb thermometer
• “The predominant cause of tree mortality in the northern deciduous forest is windthrow.”
• Gap dynamics: different species can colonize different types of disturbance gaps. “This decaying log is a stage, and the scenes take place in the gaps, where the colonists act out their drama.”
• Silvery Bryum is everywhere! “I have never traveled without encountering Bryum on my journey. It was on the tarmac in New York City and on the tiled roof outside my window in Quito the next morning.” Unlike larger organisms, mosses are truly omnipresent because their spores can travel the entire world easily.
• The artist Jackie Brookner, who alas has died since this book came out. I want to visit the boulder Prima Lingua, which is at East 9th & Ave. C in Manhattan.
• Uses of moss for diapers and sanitary napkins – knowledge male scientists didn’t get

Read for Nature & Environment – we loved it! Tudge writes beautifully. I especially enjoyed the methodical tour through all the major plant families; the notion that trees are just as dynamic as animal organisms, just not on our timescale; and the clear explanation of polyploidy (first time I’ve felt like I’m beginning to understand it).

Short quotes

• “an old kapok tree in Costa Rica in which biologists had thus far listed more than four thousand different species of creatures”
• “A forest is a forest because it has trees in it, not because it may have sloths and toucans or squirrels or chimpanzees. The trees are the prime players and the animals are the dependents.”
• “the idea … that each of us might aspire to be a connoisseur of nature, and connoisseurship implies a combination of knowledge on the one hand and love on the other, each enhancing the other.”
• What is a tree? “Many plants … have independently essayed the form of the tree. Each achieves treedom in its own way. ‘Tree’ is not a distinct category, like ‘dog’ or ‘horse.’ It is just a way of being a plant.”
• “The more that is revealed, the more wondrous nature becomes. The more we know about living creatures, the more deeply we can engage with them. This is the appetite, as Hamlet said, that grows from what it feeds on.”
• “Typically, the botanist says that two similar trees are the same, while the mateiro [indigenous expert] says they are different” and is proved right.
• “The Ducke Reserve is about a hundred thousand times smaller than the United States … yet harbors nearly twice as many kinds of native trees.”
• “It is at least possible that many local names in Maori and a thousand other languages are not meant to express particular relationships at all. After all, traditional societies—or at least the specialists within them—typically know their local flora and fauna as well as the rest of us know our friends and family. When you know everyone individually, you do not need to name them in ways that express particular relationships.”
• “The Latin names can be rather long, and sometimes too similar for comfort. If you’re sitting up late with a 40-watt bulb it’s easy to confuse, say, the Myrtaceae, Myricaceae, Myrsinaceae, and Myrsticaceae.”
• “For my part, I feel that Darwin’s is a glorious vision. I love the notion that we are literally related to all other creatures: that apes are our sisters, and mushrooms are our cousins, and oak trees and monkey puzzles are our distant uncles and aunts. Conservation, on such a view, becomes a family affair.”
• “W. D. (Bill) Hamilton proposed that it was the need to avoid parasites that prompted the evolution of sex—for sex produces the generation-by-generation variation that makes life difficult for parasites, which tend to be highly specialized, to get a hold.”

Longer quotes

Groves of redwoods and beeches are often compared to the naves of great cathedrals: the silence; the green, filtered, numinous light. A single banyan, each with its multitude of trunks, is like a temple or a mosque—a living colonnade. But the metaphor should be the other way around. The cathedrals and mosques emulate the trees. The trees are innately holy.

I’ve been fascinated by lantana since seeing it grow wild in Tucson and recognizing it as the pretty pot plant with multicolored flowers I know from the northeast, so this was an interesting anecdote:

Dr. Sas Biswas, of the Forestry Research Institute in Dehra Dun, northern India, tells a charming story of sandalwood trees he once found growing in a dead straight row in the middle of nowhere. Why were they there? Who had planted them so carefully and then abandoned them? No one, is the answer. But in the past there had been a garden; and around the garden was a fence; and along the fence grew the inevitable Lantana; and sandalwood had grown as parasites from its roots. Now the garden and the fence are long gone and the Lantana with it, but the sandalwood remains.

Mangrove tree roots breathing:

The rising tide pushes the old air out; and when it recedes, fresh air flows in again through the lenticels and pneumatophores. Thus the roots of the mangrove trees effectively breathe. They use no muscle power to do this, as an animal must. The sea is their diaphragm. The tide serves to aerate their roots; wind and fleets of obliging animals spread their pollen and seeds. Trees just don’t need the elaborations of muscle and blood and nerves on which animals expend so much.

You would not immediately suspect, if you confronted an aspen in an urban park, that it is among nature’s most resourceful trees. It has a languid air, with wanly fluttering leaves on long, flat stalks, which in autumn turn a melancholic yellow. … Yet for all its bloodless foppishness the quaking aspen has the widest distribution of any North American tree, and in large stretches of the far north it is the dominant and at times the only species.

Fig pollination dependent on specific species of fig wasps:

If we do anything to interrupt the lives of the wasps—are too free with insecticide, for instance–then we we will kill off the figs, or at least ensure that the present generation is the last. The fruits of figs are essential provender not only for bats and birds but for a host of other creatures too. In Panama, figs of various kinds are in fruit all through the year, while most other fruits are far more seasonal. There are times when figs are all there is. Take away the figs, and half the fauna could be in serious trouble. The whole ecosystem balances on a pinpoint—and we could tip it into oblivion without thinking; or, indeed, we could let it slip through our fingers even if we were trying very hard to save it. On the other hand, precarious though it seems, figs and wasps have maintained their relationship in one form or another without interruption for more than forty million years. There is robustness in the system. If only we can work with it, it might pull through yet.

In this book I learned

• Rainforest trees are especially difficult to identify and study because there are so many different species, most of them look alike, and they flower at unknown/unpredictable times.
• “[Linneaus] led botanical expeditions from his native Uppsala with the local band out in front and everyone dressed in a uniform of his own design.” Wish I could find an illustration of them!
• Bryophytes are not known to be a clade – “nobody knows the relationship between [liverworts, hornworts, and mosses], or whether they are closely related at all”
• The Lost Gardens of Heligan
• Northern conifers are tall and thin not to shed snow, but to maximize the light they get on the side, since the sun is low
• Knobcone pine and Monterey pine can enclose their old cones in wood
• Wollemia, like the coelacanth, was only known from 120 mya fossils until a group turned up in Australia in 1994
• The name “spruce” comes from “Prussia”
• Retrophyllum minus (a podocarp) is a tree that grows in running water!
• Double fertilization – Tudge’s explanation is easier for me to understand than Wikipedia’s: in angiosperm embryogenesis, “a second cell in the pollen fuses with two sets of cells in the ovule to form a combined cell with three sets of chromosomes; and this peculiar triploid cell then multiplies to form a food store, rich in carbohydrates, protein, and often fat, that surrounds the embryo.”
• Seagrasses are like marine mammals – they are land plants that moved to the water, but they still have flowers and pollen!
• Avocados have a crazy system where there are two types of flower, A and B, that can only be pollinated by the opposite flower based on time of day
• Macadamia nuts are indigenous to Australia – “the only native Australian food plants of significance to world markets”
• Sweetgum, as the name indicates, has a fragrant resin. Tudge says it’s “known as storax or styrax,” but Wikipedia uses “storax balsam” to distinguish it from “storax” aka benzoin. I am fascinated by resins, and we have introduced sweetgums around here (Liquidambar styraciflua), but I’ve never noticed their resin. Something else to look out for!
• There’s a native bittersweet, Celastrus scandens! I’ll keep an eye out – sounds like the terminal flower/berry clusters would be the easiest way to tell.
• “Golden rice” is no big deal because other plants (mangos, papayas etc.) have plenty of vitamin A. “If high-tech vitamin A-rich rice is ever of help at all, it is only in regions where traditional agriculture has been shoved aside by high-tech, industrialized, monocultural farming.”
• “a tree could grow to a height of nearly two miles if the tensile strength of water was the only constraint on its growth”
• Sebertia acuminata accumulates nickel from soil
• Parkia flowers: “pompoms of stamens and styles, bright red or pale yellow or bronze, depending on species, that hang from on high on long, thin threads like Christmas baubles”
• Dependency of tambalacoque on the dodo’s gizzard apparently is too simplistic, as they are growing fine if protected from pigs etc. “Evidently it wasn’t the presence of dodoes they required but an absence of imported herbivores. This is excellent news for the tambalacoque. But it is a pity, indeed, to kill off such an excellent story.”

I questioned these

• Tudge repeats a tidbit from the Encyclopedia of Wood, that the Paris Metro tracks are made from ekki timber (Lophira alta). I can’t find any independent confirmation, but the wood is used for railway sleepers.
• He claims “beeches that are allowed to grow into forest trees shed their leaves” (as opposed to hedges). I certainly see tons of marcescent beeches in the woods – or are those not “forest trees” because they don’t get huge before disease takes them?