In celebration of plants

In Defense of Plants: An Exploration into the Wonder of Plants by Matt Candeias 2021. Mango Publishing.

Having read a lot of books from a plants-and-people perspective lately, I’d forgotten the sheer joy of reading about plants for their own sake as awesome products of nature. That pleasure was brought back to me by In Defense of Plants by Matt Candeias [which book is here appraised].

It does what it says on the tin*

As its sub-title – An exploration into the wonder of plants – declares, this book is an unapologetic celebration of the wonder of plants. And, no matter how many books about plants I’ve read, there were lots of facts that were new to me in Candeias’ book. For example, insights into the pollination biology of leafflower trees; kleptoparasitic flies; Australian tongue orchids skewing sex ratios of pollinating wasps; seed-dispersal and thermogenesis in lodgepole pine dwarf mistletoe; blackberry’s exploitation of manganese to poison the surrounding vegetation; plant-derived methyl jasmonate turning caterpillars into cannibals; the curious association between ants and Amazonian trees, and Devil’s garden; ‘retooling’ of genes aimed at defending plants from fungal attacks to help plants consume insects; leaf-tip temperature clue to whether plant is a parasite or not; butterworts feeding on wind-borne pollen; the existence of at least one mycoheterotrophic liverwort, and a parasitic gymnosperm; Alliaria petiolata (a seemingly innocuous UK native) is one of the USA’s most pernicious alien plants, and engages in anti-mycorrhizal allelopathy… The number and variety of examples used to convey the wonder of plants should help to convince all but the most die-hard, ardent plantophobe that plants are wonderful. And Matt’s evident enthusiasm for his subject helped to rekindle any waning interest in plants this reviewer might have been experiencing.

What the book does really well…

Clearly, there is a lot of wonderful information to discover, and learn about plants. Or, as the author puts it, “These pages are filled with personal discovery and scientific wonder, and it is my hope that each of you comes away thinking about plants a little bit more in your daily life.” (p. 11). I did, and I believe others will too. And I think a lot of that is down to the very personal story that Candeias tells. For example, Chapter 1 documents Matt’s own story of plant discovery from aspiring ichthyologist to plant evangelist via restoration ecology of a site to encourage recolonization by the Karner blue butterfly (which has an important relationship with wild lupine (Lupinus perennis)). The writing is from the heart and honest, and has the evangelical fervour and zeal of the true plant convert [which is maybe not too surprising since the author confesses that he once thought plants were boring (!)]. In Defense of Plants is full of Matt’s wide-eyed wonder as he shares with the reader what he’s discovered about plants. With its highly readable style full of personal examples and anecdotes, and well-chosen tales the author truly showcases the wonder of plants. Matt’s main goal in writing this book is that “I want you to see plants … how I see plants” (p.9). Having read the book, I think it would be difficult not to: Well done, Dr Candeias!

Some suggestions for improvement…

Undoubtedly, In Defense of Plants gets a lot right – and that can only help the author get his key message across to the reader. However, there are a number of areas where the book as a whole can be ‘tightened-up’. Numerous photographs illustrate plants or phenomena – which is good to see, and nice to note that they have informative captions. Unfortunately, the quality of the images isn’t always as good as it needs to be (e.g. oswego tea on p. 56), and they are all in black-and-white. Whilst lack of colour isn’t necessarily a problem in itself, it is when colours are mentioned in the captions – e.g. “Brown patches of lily pollen can be seen on the wings of this pipevine swallowtail” (p. 84); “The bright red nectar of Nescogon mauritianus contrasts nicely with its lavender flower” (p. 98); and “The bright orange stems of dodder parasitizing a wild hydrangea (Hydrangea arborescens)” (p. 220). From pictures to words, Matt tells us he strives “for scientific accuracy in my communication constantly, this is not meant to be a textbook. … As such, I take some liberties in my choice of words (p. 10)”. Using reader-appropriate language is considerate and can help to get across biological concepts, etc. which can be quite challenging. However, accuracy must take precedence over word choice. A case in point is this statement, “At the heart of it all is photosynthesis. This wonderful biological Rube Goldberg ** allows plants to capture energy from our nearest star and use it to break apart water and CO₂ gas to build complex organic molecules like sugars” (p. 9, and essentially repeated on p. 42). Although water is broken apart during photosynthesis, in the light–dependent reactions, as far as I’m aware CO₂ is not. Instead, that molecule appears to be added in its entirety to ribulose bisphosphate in the light-independent reactions of photosynthesis via the carboxylation capacity of the enzyme RuBisCO (ribulose bisphosphate carboxylase/oxygenase). Finally, there’s no Index. Although there may be good reasons why that is the case, its absence means you need to have made pretty good notes of what’s where in the book to find it again. Since so many of the examples Matt’s provided have great educational value – as would the book as a whole, an Index would be a boon to its usefulness as a teaching resource. So, a few things that can be addressed in a future revised version of the book?

A few general words about sources…

Commenting about sources and evidence has become a major theme in my appraisals of factual books that provide plant science information (e.g. here, here, and here). But, that’s because it is important. On the plus side, In Defense of Plants provides bibliographic details to support statements of scientific fact made in all chapters (apart from the first one).*** And, with at least 34 of those sources dated more recently than 2010, that’s a good indication of the up-to-dateness of the information Matt provides. Unfortunately, there’s no easy way to relate a source to a statement because the sources are not cited within the text. Yes, readers could do the detective work for themselves and look through all of a chapter’s sources to see what relates to what statement, but that’s time-consuming and isn’t really what you’d expect to have to do [the less work the reader has to do the more s/he is inclined to view the book favourably, and recommend it to others, etc.]. Plus, since the author has done the hard work of gathering sources to support statements, why not go that extra bit further and make explicit the connections between facts and sources, e.g. by use of numbers in-text? That would be of great value to the reader, and help to ensure that the author gets appropriate credit for his academic rigour. That would not only considerably enhance its SciComm (Science Communication) (Terry Burns et al., Public Understanding of Science 12: 183-202, 2003; https://doi.org/10.1177/09636625030122004) credentials, but would also make the book feel more ‘joined-up’. Something else to consider for a revised version of the book?

And some specifics…

Rather than just make general comments about statements-and-sources, here are two specific instances. I’d dearly like to know the source for this dramatic statement from Chapter 7 on parasitic plants: “Yet, with nearly fifty percent of the lifeforms on our planet adopting a parasitic lifestyle in one form or another…” (p. 211). None of the 11 sources listed for that chapter look to be likely sources for that astonishing claim – by scrutiny of their titles only, I didn’t have time to read any of them to see if they contained that arresting ‘statistic’. It would also be nice to know the source of this assertion: “… plants are incredible living organisms that conquered land long before any animal crawled out of the ocean” (p. 8). As a lifelong botanophile I’d dearly love this to be true, and am understandably keen to know the source that supports the claim so I can use it. Sadly, one is left to guess where this information comes from because this statement is in the Preface, one of the sections of the book with no dedicated Bibliography. My own researches suggest that Matt’s statement may not be correct. Or, rather, that its veracity depends upon which sources one consults. However, I’ve found a source that states, “The oldest fossils of footprints ever found on land hint that animals may have beaten plants out of the primordial seas” (Tom Clarke, 2002, Nature doi:10.1038/news020429-2), and another which says: “New analyses suggest that animals colonized land sooner than previously thought, and maybe even before embryophytes (land plants)” (Casey Dunn, Current Biology 23: R241-R243, 2013; https://doi.org/10.1016/j.cub.2013.01.067). Both of which sources can be cited, are evidence-based, and cast doubts on the validity of Candeias’ assertion. But, these matters can easily addressed by a revised edition of In Defense of Plants…

Let’s finish on a positive…

It’s Matt’s hope that with the increased knowledge about plants gained from the book will come better understanding – and appreciation – of plants. But, it’s not just plants as wonderful organisms in their own right, it’s also recognising plants as major influencers of habitats and the environment. In that regard, if you look after the plants you are going a long way to looking after the rest of the ecology of an area. And that’s a major message in the book’s last chapter. In parts that reads like an ‘eco-agitator’s’ manifesto, wherein Candeias does his best to encourage all of us to make a difference – for the better! – to the plant life in our local communities. If we each do our little bit locally, all of those small individual interventions aggregated with others will soon generate a nationwide and global force for change – for the good of plants and for the benefit of people and the planet. But, if you’re not ready to go out and ‘man the barricades’ just yet, reading In Defense of Plants is a very good place to start. And, who knows, it may even inspire you to start up your own branch of the PDL (Plant {Defence/Defense – word choice depending on which version of English is preferred} League).

Summary

Author Candeias proudly declares, “I am here to defend plants” (p. 11). But, do plants need to be defended? Probably. They are under threat generally from factors such as habitat loss and global climate change; native flora are also under threat specifically from introduced alien plant species. Many of these existential threats are due to human actions and are included in Matt’s book. Plants, therefore, do need to be defended – from us, from people, and it’s people that need to do the defending. But mobilising the people can be difficult if they don’t have a good reason to act. It’s no good just saying that plants are wonderful and need to be protected, their would-be defenders need to be shown the wonder of plants in order to be convinced. Along with the author, I hope that Matt Candeias’ In Defense of Plants will do its bit to help persuade a sceptical public that plants need to be defended by showing them how wonderful plants are. But, that can only work if people read the book, and this I strongly encourage everybody to do.

* This is an informal phrase in common usage in the UK which effectively means that the product provides what it promises.

** I believe this is a reference to American Rube Goldberg who drew incredible gadgets. In the UK, we may be more familiar with the notion of Heath Robinson contraptions.

*** I’d be failing in my book-appraising duty if I didn’t also mention that several of the citations appear incomplete. Some scientific articles appear to be missing volume numbers (e.g. Gerlach (2011) (p. 269); Smith (1950) (p. 270); Kerlin & Andrus (1995) (p. 270)) or page numbers (e.g. Gerlach (2011) (p. 269); Randriamalala & Liu (2010) (p. 277)). More information is probably needed for theses so they could be tracked down by interested readers – e.g. Smith (2009) (p. 268); Pokladnik (2008) (p. 277). What sort of source is Borer (p. 276)? It has no date and one can’t tell if it’s a book, a scientific article, or what. And I’m not sure what has happened regarding the entry for Fadrique et al. (2019) (p. 276). Yes, appropriate ‘Googling’ will probably allow the curious to track down the originals, but … Anyway, all of these – and the others not itemised – are probably easily dealt with – in a revised edition?