Botany for Gardeners

238 Pages·2004·3.727 MB·English

by  Brian Capon

BotGar_Cover (5-8-2004) 11/8/04 11:18 AM Page 1
$19.95/£14.99 GARDENING & HORTICULTURE/Reference
Botany for Gardeners
offers a clear explanation of how plants grow.
•What happens inside a seed after it is planted?
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•How are plants structured?
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•How do plants adapt to their environment?
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•How is water transported from soil to leaves?
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•Why are minerals, air, and light important for healthy plant growth?
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•How do plants reproduce?
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The answers to these and other questions about complex plant processes,
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written in everyday language, allow gardeners and horticulturists to
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understand plants “from the plant’s point of view.”
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Abestsellersinceitsdebutin1990,BotanyforGardenershasnowbeenexpanded d
Botany for Gardeners
and updated, and includes an appendix on plant taxonomy and a comprehensive e
index.Twodozennewphotosandillustrations n
make this new edition even more attractive e
than its predecessor. r REVISED EDITION Brian Capon
s
Brian Capon received a ph.d.in botany
from the University of Chicago and was for
thirty years professor of botany at California
State University, Los Angeles. He is the
author of Plant Survival: Adapting to a Hostile
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World, also published by Timber Press. r
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Author photo by Dan Terwilliger. n

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For details on other Timber Press books or to receive our a
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catalog, please visit our Web site, www.timberpress.com.
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In the United States and Canada you may also reach us
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at1-800-327-5680, and in the United Kingdom at
[email protected].
ISBN 0-88192-655-8 ISBN 0-88192-655-8
90000
TIMBER
PRESS
0 08819 26558 0 9 780881 926552
UPC EAN
001-033_Botany 11/8/04 11:20 AM Page 1
Botany for Gardeners
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001-033_Botany 11/8/04 11:21 AM Page 3
Botany for Gardeners
Revised Edition
Written and Illustrated by
BRIAN CAPON
TIMBER PRESS
Portland*Cambridge
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Cover photographs by the author.
Text copyright © 2005 by Brian Capon
Photographs and drawings copyright © 2005 by Brian Capon
All rights reserved
Published in 2005 by
Timber Press, Inc. Timber Press
The Haseltine Building 2 Station Road
133 S.W. Second Avenue, Suite 450 Swavesey
Portland, Oregon 97204-3527, U.S.A. Cambridge CB4 5QJ, U.K.
www.timberpress.com
Printed through Colorcraft Ltd., Hong Kong
Library of Congress Cataloging-in-Publication Data
Capon, Brian.
Botany for gardeners / written and illustrated by Brian Capon.-- Rev.
ed.
p. cm.
Includes index.
ISBN 0-88192-655-8 (pbk.) -- ISBN 0-88192-655-8
1. Botany. 2. Gardening. I. Title.
QK50.C36 2005
580--dc22 2004003695
A catalog record for this book is also available from the British Library.
001-033_Botany 11/8/04 11:21 AM Page 5
CONTENTS
Introduction 9
PART I. GROWTH 13
Chapter 1
Cells and Seeds: Basics and Beginnings
Cells 16
Cell Walls 18
Wall Structure and Cell Growth 20
Growth Processes 22
Meristems 22
Seed Coats 24
Food-Storage Structures and the Embryo 25
Seed Germination 29
Other Germination Requirements 31
Chapter 2
Roots and Shoots: How Plants Mature
Root Systems 34
Root Growth 36
Root Hairs and Branches 37
Primary Growth in Stems 38
Development of a Woody Twig 44
Features of a Woody Twig 45
Leaves 47
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6 Contents
PART II. ORGANIZATION 53
Chapter 3
Inside Stems
Herbaceous Stems 56
Stem Thickening 59
Other Features of Wood 64
Monocot Stems 67
Chapter 4
Inside Roots and Leaves
A Root’s Primary Tissues 71
Secondary Growth in Roots 73
Cellular Organization in Leaves 74
Plant Cell Types 79
PART III. ADAPTATION 83
Chapter 5
Adaptations for Protection
The Garden Habitat 87
Environmental Modification 88
Limiting Factors 91
Protection in Extreme Environments 92
Protection against Animals 96
Protection by Camouflage 99
Protection by Ants 100
Wound Healing 101
Chemical Protection 103
Mode of Operation of Chemical Protectants 106
Other Methods of Defense 108
Chapter 6
Adaptations to Fulfill Basic Needs
Competition between Plants 109
Reaching toward the Sun 110
Spreading Stems 111
Climbing Structures 113
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Contents 7
Lianas and Epiphytes 115
Supportive Roots 115
Special Methods of Water Uptake 117
Adaptations for Water Storage 118
Underground Food- and Water-Storage Organs 120
Saprophytes and Parasites 124
Mycorrhizae and Root Nodules 126
Insectivorous Plants 128
PART IV. FUNCTIONS 131
Chapter 7
Control of Growth and Development
Growth Responses to Light 134
Responses to Gravity and Touch 137
Other Growth Movements in Plants 140
Hormones and the Aging Process 141
Control of Branching and Adventitious Root Formation 143
Other Hormone Effects: Synthetic Growth Regulators 144
Environmental Control: Temperature 145
Vernalization 147
Environmental Control: Photoperiod 148
Chapter 8
The Uptake and Use of Water, Minerals, and Light
Osmosis: The Cell’s Water Pump 152
Development of Root Pressure 155
Transpirational Pull 156
Cold Hardening 158
Mineral Nutrient Needs 158
Soils 163
The Photosynthetic Apparatus 165
Light Transformed into the Energy in Food 168
The Photosynthetic Process 169
Gas Exchange with the Atmosphere 172
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8 Contents
PART V. REPRODUCTION 175
Chapter 9
From Flowers to Fruits
Flower Parts and Their Functions 178
Pollination by Animals 182
Road Maps and Rewards 183
Inflorescences 186
Pollination by Wind and Water 189
Pollination Alternatives 191
The Reproductive Process 193
Seedless Fruits and Unusual Embryos 195
Fruit Types 195
Seed Dispersal 198
The Cost of Reproduction 200
Chapter 10
Strategies of Inheritance
Genetics: The Science of Heredity 201
Mitosis and Meiosis 202
The Life Cycle of a Moss 203
The Life Cycle of a Fern 205
The Two Generations of Flowering Plants 207
Chromosome Segregation during Meiosis 209
Gene Segregation during Meiosis 210
Consequences of Imperfection 213
The Origins of Polyploidy 214
Custom-made Plants of the Future 217
Epilogue 219
Appendix: Plant Names 220
Glossary 224
Index 234
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INTRODUCTION
Earth has been called the green planet, a world
clothed in a mantle of vegetation that sustains all other forms of life on this
tiny spot in the universe. From simple beginnings, plants evolved first
among Earth’s living things and thereby established a fundamental princi-
ple of nature: Plants, in one form or another, can exist forever without ani-
mals, but animals cannot exist without plants.
Plants purify the air by exchanging the oxygen we breathe with carbon
dioxide, which is poisonous in too high a concentration. Plants convert the
energy of sunlight into foods that sustain all animals and, from the soil,
draw minerals such as nitrogen, potassium, calcium, and iron that are essen-
tial for our well-being. For creatures large and small, plants provide shade
from the sun, refuge from predators, and protection from the ever-chang-
ing elements. Since the first cells came into being millions of years ago,
plants have been the connecting links in an unbroken chain of life. It is they
that have made the biosphere, the part of Earth’s crust where both plants
and animals exist, a place of limitless opportunity for human inquiry.
The range of uses we make of plants is as broad as our ingenuity permits.
We have exploited them for fibers to make cloth, drugs to cure a multitude
of ailments, and wood to construct houses, furniture, and ships. From them
we have extracted raw materials to manufacture innumerable goods, includ-
ing paper. Without that latter commodity, the detailed history of our race
would not have been recorded and so remembered, nor could knowledge
have been so easily disseminated. And culture, the possession of which
makes humans out of animals, would never have developed beyond the
basic skills and habits of primitive peoples had we not had paper on which
to write music, poetry, and prose.
Some of us look at plants as a source of livelihood, while others find
them intriguing subjects for scientific study. But most enjoy plants for the
sheer delight of having them in their everyday surroundings, to savor the
varied colors, textures, tastes, and aromas that they alone can offer. Plants
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