Jill Severn's Gardening Column

Why don't ferns have flowers?

Posted

In his book Inside Plants, A Gardeners’ Guide to Plant Anatomy and Physiology, local author Gary A. Ritchie, Ph.D., begins at the beginning.

The earth, he notes, is estimated to be 4.54 billion years old; the first hints of plant life appeared about 3 billion years ago. “Organisms that we would recognize as plants did not arise until just before the Cambrian period,” he writes. That was a mere 541 million years ago.

The first flowering plants came even later; they didn’t evolve until 145 million years ago. (This makes me glad I’m alive now; it would be sad to live on a planet without flowers.)

This is a mind-expanding book, written by a retired research scientist in plant physiology who is also the president of the local Rose Society and a dedicated gardener.

His review of the history of our spinning planet and all the plant life that rides around on it is vivid and enchanting. Now when I see West Virginia Senator Joe Manchin on the news, I will think of the Carboniferous Period, about 350 million years ago, when horsetails, club mosses and ferns lived and died and became the great coal fields in his state.

He also writes a marvelous description of a plant cell, which he describes as “being analogous to a city with complex systems and subsystems” that provide “infrastructure, security, cellular regulation, intracellular synthesis and assembly, food production, and energy management.” With all that activity inside every plant cell in every plant around us, it’s a wonder we can’t hear it.

There is a great deal in this book I will probably never understand because I never took chemistry and was a dud in math classes. But even though I’ve only read the first five chapters so far, it has already deepened my appreciation for the history, complexity and wonder of how the evolution of plant life made the evolution of humans possible by providing oxygen to breathe and food for animal life.

When Ritchie gets deep into the science, I’m lost. But he writes plainly and appealingly about basic concepts and context. For instance, here’s his introduction to photosynthesis:

“Ask any third-grade student how plants make food and he/she will shout out: ‘Photosynthesis.’”

“But then ask them how photosynthesis works and you’ll get a blank stare. Actually, ask any adult how photosynthesis works and you’ll get a blank stare. The simple fact is that, while photosynthesis is pretty straightforward in principle – plants use sunlight and CO2 to make sugar – the processes by which this happens are frightfully complicated. So complicated that, while most of the major steps in photosynthesis have been worked out, much remains enigmatic to even the brightest scientists.”

A couple of pages later, he’s deep into thylakoid membranes, chloroplasts, photons and the dark reaction or Calvin cycle, and I am left behind. But even if I never catch up, I’ll always be grateful for this yardstick of my own ignorance. This book is guaranteed to keep the non-scientist humble.

But it also has its share of practical advice, including how to prevent photodamage – aka sunburn – on geraniums that spent the winter in a garage, or plants that have grown in cloudy conditions and are suddenly confronted by bright sunny days. The key is helping them make gradual rather than sudden changes. One strategy is providing them with an umbrella for shade for a few days, which, Ritchie notes, might amuse your neighbors.

I’m glad to own this book. I’ll keep reading the useful chapter introductions and summaries, and study the excellent graphs and illustrations. I commend it to all gardeners and naturalists who seek a deeper understanding of the exquisitely complex miracle of life on earth.

Inside Plants  is available here.

Jill Severn writes from her home in Olympia, where she grows vegetables, flowers and a small flock of chickens. She loves conversation among gardeners. Start one by emailing her at  jill@theJOLTnews.com

Comments

No comments on this item Please log in to comment by clicking here