Saturday Morning Science (Moss Edition)

Recently I went and visited my family in Washington and noted that there was a lot of moss around all the trees there. I don’t have a lot of moss in the forest where I live. I figured it had to do with the amount of rain, as we generally have a warmer, drier climate.

But then I went out to my forest between the rain this week, and was struck by the sight of an enormous tree completely coated in moss. The entire trunk was green.

But none of the trees around it had any moss. Poking around a bit more, I realized that all the trees with moss were Douglas firs, and the trees without (but often with a lichen?), were redwoods. This remained true wherever I went, suggesting it wasn’t some something to do with that particular tree’s environment. Being very much not a plant scientist (or a moss scientist), I didn’t know much about what was going on, and wondered if the species-specific moss growth had to do with something structural (is redwood bark too smooth for moss to grab on to? do douglas firs move water/nutrients in a way that moss can better appreciate?), or chemical (do redwoods deter moss growth?). I decided the chemical deterrent hypothesis made more sense, because I found moss on old redwood stumps that had lost most of their outer bark.

Having wasted a great deal of time eating lunch and staring at trees, I went back to the lab and did some reading:

In non-moss related news:

Book Pairings: Botanical Intelligence

Welcome to the first of probably many posts in which I share book (and sometimes other media) recommendations on a theme…

Plants somehow became a major theme of 2018’s reading. I think it happened because at the beginning of the year I made a resolution to really pay attention to the world around me as part of Operation Un-depress Myself. I told myself to look at the trees on my walk from home to the bus stop or wherever I was going, and pay attention to how they changed with the seasons.  It kind of worked. The side effect was a newfound fascination with all the ways plants have evolved to survive and adapt to changes.


Book #1: Semiosis, Sue Burke
I had been wanting to read this one since before it was published; the promise of intelligent alien plants and language and interspecies interaction sounded like my kind of sci fi. I had mixed feelings about the style, but I found the creativity Burke put into her vegetal species refreshing and really fascinating after having read so much about real plant adaptations. If you’re looking for fleshed-out human characters, this isn’t really the place, as the book spans several generations to explore how people establish a civilization on a new planet and build relationships with the other forms of life already there. 


Book #2: Braiding Sweetgrass: Indigenous Wisdom, Scientific Knowledge, and the Teachings of Plants, Robin Wall Kimmerer
I loved this book. Kimmerer is a good and thoughtful communicator, and her writing about the wonders of nature and the immense value of indigenous knowledge in understanding and working with the environment are refreshing and illuminating. So much of this book resonated with me; I wish more people shared her perspective in the scientific world and the world at large. Ultimately while this book celebrates nature’s ingenuity, it is also about people and our relationship with nature.


Book #3: The Songs of Trees: Stories from Nature’s Great Connectors, David George Haskell
Honestly I could have recommended any of a number of other books in the genre of lyrical explorations of plant biology, but I preferred the style of this one. Each chapter revolves around a particular tree and delves into its web of interactions, revealing fascinating bits of history, botany, and ecology. As runners-up (choose your own tree adventure): The Hidden Life of Trees, The Botany of Desire: A Plant’s-Eye View of the World, or The Wild Trees: A Story of Passion and Daring.