Introduction to California Plant Life [Rev. ed., Reprint 2020] 9780520936959

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CALIFORNIA NATURAL HISTORY

INTRODUCTION CALIFORNIA PLANT

LIFE

TO

GUIDES

California Natural History

Guides

Phyllis M. Faber and B r u c e M. Pavlik, G e n e r a l Editors

Introduction to

We dedicate this revision to the memory of Robert Ornduff (1932-2000), plant lover par exellence and friend.

California Natural History Guides No. 6 9 University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England © 2003 by the Regents of the University of California Library of Congress Cataloging-in-Publication Data Ornduff, Robert. Introduction to California plant life / Robert Ornduff; revised by Phyllis M. Faber and Todd Keeler-Wolf.—Rev. ed. p. cm.—(California natural history guide series; 69) Includes bibliographical references and index. ISBN 978-0-520-23704-9 (pbk.: alk. paper) 1. Botany—California. 2. Plant ecophysiology—California. 3. Plants— Identification. I. Faber, Phyllis M. II. Keeler-Wolf, Todd. III. Title. IV. Series QK 149.073 2003 581.9794—dc21 Manufactured in China 17 10 9 8 7 6 5 4

2002032078

3

The paper used in this publication meets the minimum requirements of ANSI/NISO Z39.48-1992 (R 1997) (Permanence of Paper). © Cover image: Blue oak {Quercus douglasii). Photo by John D. Stuart.

The publisher gratefully acknowledges the generous contributions to this book provided by the Moore Family Foundation Richard & Rhoda Goldman Fund and the General Endowment Fund of the University of California Press Associates.

Grateful acknowledgment is also made to the California Academy of Sciences.

CALIFORNIA. A c AI>EJMY < >1

SCIENCES

CONTENTS

1.

2.

3.

Preface Preface from the 1974 Edition Introduction

x xiii xv

THE CALIFORNIA FLORA

2

The Californian Floristic Province

4

Diversity of the Flora

6

Naming Plants: Latin Binomials and Common Names

17

The Meanings of Plant Names

21

A Hierarchy of Classification

28

Naming New Plant Species

31

Rarity and Endemism

34

CALIFORNIA'S TOPOGRAPHY, CLIMATE, AND SOILS

40

Topographical Features of California

42

Climate

50

Geology and Soils

58

PHYSICAL AND BIOLOGICAL INFLUENCES ON PLANTS

68

Soil and Topography

70

Sun and Wind

72

Effect of Shade

72

4.

Competition for Water and Light

73

Water and Salinity

74

The Presence of Fire

75

Fungi and Bacteria

77

Plant Competition and Allelopathy

79

Herbivory

80

Pollination

80

Seed Dispersal

86

Adaptations to Aridity

88

Reading the Landscape by Indicator Species

93

V A R I A T I O N OR

ECOTYPES

OF P L A N T S P E C I E S Climatic Ecotypes

5.

6.

7.

96 98

Soil Ecotypes

105

I N T R O D U C T I O N TO CALIFORNIA VEGETATION

110

Vegetation and Flora

112

Concepts of Plant Community and Vegetation

113

A Classification System

115

Ecological Dominance

119

Plant Succession

121

Life Zones

125

V E G E T A T I O N T Y P E S IN CISMONTANE CALIFORNIA

150

The Cismontane Region (West of the Sierra Nevada Crest)

152

V E G E T A T I O N T Y P E S IN M O N T A N E AND TRANSMONTANE CALIFORNIA

198

Montane Region (High Mountain Areas)

200

Transmontane Region (Areas East of the Sierra Nevada Crest and the Deserts)

8.

EVOLUTION OF THE CALIFORNIA FLORA Arcto-Tertiary Geoflora

9.

212

228 231

Neotropical Tertiary Geoflora

236

Madro-Tertiary Geoflora

237

Fossil History of Coast Redwood

241

EARLY PLANT EXPLORATION AND BOTANY IN CALIFORNIA Early Explorers

246 248

Early Plant Collectors

252

The First American Explorers

257

Surveys for Railroads

263

Botany in California Since Statehood

265

10. RECENT CHANGES IN CALIFORNIA'S FLORA

270

Climate Change

272

Native American Usage of the Land

273

The Impact of Agriculture and Grazing

276

The Impact of Invasive Weeds

277

Tracking Habitat Destruction and Loss of Species

284

Habitat Restoration

288

Saving Biodiversity: A Call for Action

290

Glossary Supplemental Reading References Art Credits and Additional Captions Index of Plant Names General Index

297 301 303 315 317 331

PREFACE

An Introduction to California Plant Life, written by Professor Robert Ornduff and published in 1974, has in the intervening years introduced many thousands of students to California's unique flora. During the nearly 30 intervening years, however, a number of new findings have occurred in the field of botany. Changes in the taxonomic treatment of plants have resulted in the reclassification of several plants,, and studies have led to new information regarding several aspects pertaining to the plants of California. Dr. Ornduff died in September of 2000 before he could make needed revisions to his book. Since his death, Dr. Todd Keeler-Wolf, vegetation ecologist with the California Department of Fish and Game, and I have taken on the assignment to update it. Our goal throughout has been to maintain the integrity of Bob's original work, as his extensive knowledge and love of the California flora remains unmatched. In light of recent taxonomic changes, scientific plant names in this revised edition conform to The Jepson Manual: Higher Plants of California (Hickman 1993), and the common names used are preferentially from the Jepson Manual, the CNPS Inventory of Rare and Endangered Vascular Plants of California (Tibor 2001), or A California Flora (Munz 1968). Todd has added a discussion of "vegetation type," a term more currently in use than "plant community." A controversy over these terms was noted even in the first edition of this book. We have retained the selection of plant communities

Ornduff described because they continue to represent in broad terms the basic assemblages of plants found in California. The seven chapters of the 1974 edition have been increased to 10, with discussions of biological and physical influences on plant life and plant ecotypes separated into two chapters, and the evolution of the California flora and present human influences also in two chapters. We have added a chapter, chapter 9, on early explorers and plant collectors, the first part of which was written by Dr. Elizabeth McClintock of the California Academy of Sciences. Her material originally appeared in the California Horticultural Society Journal (McClintock 1967). The full chapter appeared with minor changes in a syllabus, prepared by Dr. Ornduff for the University of California Extension course, Integrative Biology xl 13 in 1992. Chapter 10 contains an expanded discussion of plant conservation topics and some of the impacts of human activities on native plants and plant communities. A reference list, originally provided for each chapter with an additional general list, has been merged into a single reference list and updated. We also have added a short, supplemental reading list and a small glossary. Many people have helped to make this revision better. Richard Moe from the University of California Herbarium has assisted with taxonomic nomenclature and species numbers, and Roxanne Bittman from the Natural Diversity Data Base helped with rare plant information. A number people have reviewed parts or all of the manuscript: an anonymous reviewer saw three versions of the manuscript; Frank Almeda and Paul di Silva both reviewed an early version, Diane Renshaw critiqued chapter 10; and Pam Muick and Emily Roberson each added information to chapter 10. All have been generous with their knowledge, time, and suggestions, and we thank each of them. Because of better printing technology, many new photographs have been added to this edition, some from the Orn-

PREFACE

xi

duff collection but many from other sources. John Game and Wilma and Bill Follette deserve special mention for graciously providing numerous photographs on short notice. Drawings in the original publication were redrawn by Peter Gaede, map 1 was provided by Paula Nelson, maps 2,3, and 4 were redrawn by William Nelson, and water color illustrations are by Virginia Bates. We hope that those who read and learn from this book will appreciate and enjoy California's unique plants and natural landscapes and will play an active role in preserving them. Phyllis M. Faber June 2002

xii

PREFACE

PREFACE FROM THE 1974 EDITION

To many Californians, the wealth of the state lies in its gold, its petroleum, its timber, or its fertile valleys. To those of us who are amateur or professional botanists, or who simply enjoy "plant watching," the riches of California are also reflected in the diversity of wildflowers, shrubs, and trees that occur throughout the state. California is isolated from the rest of North America by deserts or mountains that have allowed the development within its boundaries of one of the most varied floras that occurs anywhere on earth. The plant cover ranges from the forests of the northern coast and the mountain slopes, to the woodlands and scrublands of the foothills and deserts, to the grasslands of the valleys. Our plants range in size from the stately Coast Redwoods of the fog-shrouded coast to the minute belly plants of the southern deserts, and in age from the venerable four-thousand-year-old Bristlecone Pines to the diminutive ephemeral annuals whose life span can be counted in weeks. This small book introduces you to the plant life of California and tells you something of how plants are grouped into communities and what environmental influences determine the pattern of distribution of these communities in the state. It also discusses the origin of our flora, how plants are adapted to the diverse climates of the state, and how they respond to

xiii

forest and chaparral fires, to unusual soils, to man, and to each other. The contents of this book are adapted from a syllabus that I wrote for an Independent Study course developed for the University of California, Berkeley. Because most of my botanizing has been in northern California, the contents of the book are perhaps unevenly weighted toward this portion of the state. Drafts of portions of the manuscript were read by L. R. Heckard, J. R. McBride, D. R. Parnell, and a few other friends and colleagues to whom I am indebted for helpful suggestions. I am also grateful to S. C. H. Barrett, R. Benseler, S. Carlquist, D. Hafner, L. M. Moe, and A. C. Smith for allowing me to reproduce their slides, to C. Mentges for executing the line drawings, and to R Watters for her assistance in preparing the manuscript. Several of the color illustrations have been taken from the slide collection of the Jepson Herbarium, University of California, Berkeley. I am also indebted to my students, who have proven time and again that there is still a great deal that I have to learn about California plants, and that most of this will be gained by studying the plants themselves and not what is written about them in books. Map 1. Major topographical features of California. The portion of the state in the California Floristic Province is to the coastward side of the hatched line. Robert Ornduff June 1974

xiv

PREFACE FROM THE 1974

EDITION

INTRODUCTION

Nearly one-fourth of the plants found in North America north of Mexico, and more than are found in any other state, grow in California. Around 6,000 species, subspecies, and varieties of native flowering plants, conifers, and ferns grow in woodlands, deserts, mountains, and wetlands of California, some from the days when dinosaurs roamed the earth and some of far more recent origin. California is home to the world's tallest trees, the coast redwood (Sequoia semperviretts), the world's largest trees, the giant sequoia (Sequoiadendron giganteum), and the world's oldest trees, the western bristlecone pine (Pinus longaeva). The extraordinary diversity found in California's native plants is a reflection of the complex geologic history, diverse topography, and climate of the area now called California that has changed dramatically over the eons. Particles eroded from base rocks combine with organic matter to slowly form soils. Where an area is wet and warm, soils form faster, where dry and hot, soil formation can be almost nonexistent. Today's vegetation is a reflection of environmental conditions found in years past together with conditions found today. As conditions change, some plants can persist, whereas others cannot and become extinct. Fan palms (Washingtoniafilifera), for example, are relics from 60 million years ago when the region was less mountainous and the climate tropical; the coast redwood and the giant sequoia are remnants from 40 million years ago when the climate was cooler and wetter; and some

XV

of the oaks and desert shrubs we see today are descendents of species that evolved in the warmer, drier period of 10 million years ago. Because plants occur where environmental conditions meet their needs, understanding the subtle factors that affect plant distribution can be interesting and a challenge. Noting features such as slope direction, soil depth, history of disturbance, intensity of shade, and availability of moisture enable prediction of the assemblages of plants that might be expected, or the understanding of why certain plants so often grow together. California'a landscape is rich and varied, with dozens of vegetation types ranging from those found on coastal bluffs and dunes to towering montane forests. The stunning beauty of the annual spring wildflower displays on coastal terraces and on valley slopes alone brings visitors from around the world. As the population of this state continues to expand rapidly, being good stewards of this rich resource becomes a daunting challenge. Gaining an understanding and enjoyment of the plant life found in this state is a good place to begin.

xvi

INTRODUCTION

CHAPTER 1 THE CALIFORNIA

FLORA

The Californian Floristic Province California is a large state with a complex topography and a great diversity of climates and habitats, resulting in a very large assemblage of plant species that vary in size and include both the world's largest trees and some of the smallest and most unique plant species. In order to create manageable units for plant investigations, botanists have divided the continental landform into geographic units called floristic provinces. These units reflect the wide variations in natural landscapes and assist botanists in predicting where a given plant might be found. Within the borders of California, there are three floristic provinces, each extending beyond the state's political boundaries. The California Floristic Province includes the geographical area that contains assemblages of plant species that are more or less characteristic of California and that are best developed in the state. This province includes southwestern Oregon and northern Baja California but excludes certain areas of the southeastern California desert regions, as well as the area of the state that is east of the Sierra Nevada-Cascade Range axis (map 1). The flora of the desert areas and those east of the Sierra Nevada crest are best developed outside the state, and therefore, parts of the state of California are not in the California Floristic Province. The Great Basin Floristic Province includes some of the area east of the Sierra Nevada and some regions in the northeastern part of the state, although some botanists consider the latter area to belong to another distinct floristic province, the Columbia Plateau Floristic Province. A third floristic province partly located within California is the Desert Floristic Province, which makes up the southeastern portion of California. The climate in this province is unpredictable from year to year, but rainfall is uniformly scarce.

4

THE CALIFORNIA

FLORA

Diversity of the Flora The Jepson Manual: Higher Plants of California (Hickman 1993), the current authority on the higher plants of California, includes 7,000 vascular plant taxa (species, subspecies, and varieties) as occurring in California outside of cultivation. Of these, 5,862 are considered native, and 1,023 are presumed to have been introduced during the immigrations of the eighteenth through twentieth centuries. The Jepson Manual defines vascular plants as having a well-developed vascular system to transport water, dissolved minerals, and other substances throughout the plant body. Club mosses, horsetails, ferns, gymnosperms, and flowering plants are vascular plants; fungi, algae, mosses, and liverworts are not. These 7,000 taxa are distributed in The Jepson Manual among 1,227 genera and 173 plant families, with 19 families consisting entirely of naturalized (nonnative) species. Of the 5,862 native taxa, 4,693 are considered distinct species, and 1,169 are considered varieties or subspecies. There are 1,416 species endemic to California—that is, they are found nowhere else in the world— and 737 endemic varieties or subspecies. At least 26 endemic species are presumed extinct. The large number of endemic species is the result of the great diversity of climate, soils, and topography found in California.

TABLE

l. Six Largest Families in California Alternative Family Name

Number of Genera

Asteraceae (sunflowerfamily)

Compositae

185

907

Poaceae (grass family)

Gramineae

106

438

Fabaceae (pea family)

Leguminosae

44

400

Family

Scrophulariaceae (figwort family) Brassicaceae (mustard family) Cyperaceae (sedge family)

6

THE C A L I F O R N I A

FLORA

Cruciferae

Number of Species

30

313

56

279

14

210

In the 10 years since The Jepson Manual went to press, scientific understanding of California plants has continued to advance, and botanical collections from previously unvisited locations have led to new discoveries. As a result, the numbers of species given in the 1993 manual are already somewhat out of date. The California Native Plant Society's Inventory of Rare and Endangered Plants of California (Tibor 2001), which uses somewhat different definitions or limitations defining rarity than does The Jepson Manual, estimates that there are 6,300 California native plants. The Jepson Herbarium located at the University of California, Berkeley, has begun a program, the Jepson Interchange, that is intended to follow and evaluate proposed changes in the taxonomy of California higher plants. The six largest plant families, with approximate numbers, are listed in table 1. A simple analysis of the numbers in table 1 reveals that 40 percent of the species of vascular plants in California belong to only six families. You can simplify the task of identifying plants in any part of the state by learning the distinguishing characteristics of these six families, listed here. In the sunflower family (Asteraceae) (fig. 1, pi. 1), flowers are in a dense head and have disk florets, ray florets, or both. The heads are surrounded by bracts, and the anthers are generally fused into cylinders around the style. The calyx is c ììi^M

a

b

d

e

Figure 1. Sunflower family (Asteraceae). (a) Sunflower, (b)goldfield, (c) portion of flower head, (d) details of disk floret, (e) dandelion, (f) thistle.

THE

CALIFORNIA

FLORA

7

Plate 1. Sunflower family (Asteraceae), balsam-root (Balsamorhiza sagittata).

represented by a scaly or bristly pappus on the one-seeded inferior ovary. Members of the sunflower family include sunflowers (Helianthus spp.), asters (Aster spp.), ragweeds (.Ambrosia spp.), sagebrushes (Artemisia spp.), goldfields (Lasthenia spp.), pineapple weed (Matricaria matricariodes), thistles (Cirsium spp.),balsam-root (Balsamorhiza sagittata), tarweeds (Madia spp. and Hemizonia spp.), and dandelions (Taraxacum spp.). In the grass family (Poaceae) (fig. 2, pi. 2), flowers are very small, greenish, and inconspicuous, and the stamens, pistil, or d

Ì

1 ' ;

v

,

ì I/if I

l Vi f

> >•

' 7 4 - 7 5 , 9 4

261 University of California, Berkeley,

water loss adaptations, 7 2 , 9 2 , 9 3 , 1 7 8 , 179

266-267 Jepson Herbarium, 7 , 2 6 8 - 2 6 9 University o f California Natural Reserve System classification, 114,

weed eradication, 284 weeds, invasive, 2 7 3 , 2 7 7 - 2 8 4 native species, 283 Weiss, Martha, 8 3 - 8 4

116 University o f California Press, 269 Upper Sonoran life zone, 130-132

wetlands habitat restoration, 288 loss of, 1 6 2 - 1 6 3 , 1 9 7 , 2 8 4

Valley and Foothill Woodland, 118, 143,185-187,238

marshes; vernal pools

Valley Grassland, 1 1 8 , 1 4 3 , 1 8 7 - 1 9 1

Whipple expedition, 263

Valley Sonoran/Great Valley life zone,

Wiggins, I.L., 268 wildlife. See animals

129-130 Vancouver expedition, 2 5 0 - 2 5 1

Wilkes Expedition, 2 5 9 - 2 6 0

variability. See ecotypes

wind adaptations, 72

varieties, 1 9 , 2 8 4 - 2 8 5

wind pollination, 82

vascular plants, number o f taxa, 6 - 7

winds, 5 7 , 7 2

Vasek, Frank, 224

woodland vegetation types

vegetation types classification systems compared,

340

See also Freshwater Marsh; salt

Joshua Tree Woodland, 118,148, 220-222

113-116,118,137-139

Pinyon-Juniper Woodland, 118,

distribution maps, 116-117

1 4 6 - 1 4 7 , 2 1 2 - 2 1 3 , pi. 139

GENERAL

INDEX

Riparian Woodland, 118,144, 191-194 Valley and Foothill Woodland, 118, 143,185-187,238 Wash Woodland, 224-225,227 See also oak woodlands

wool imports, weeds and, 279 xerophytes, 92-93,178 Yellow Pine Forest, 118 Zoe (journal), 266

GENERAL

INDEX

341

Series Design: Design Enhancements: Design Development: Composition: Cartographers: Text: Display: Printer and Binder:

Barbara Jellow Beth Hansen Jane Tenenbaum Impressions Book and Journal Services, Inc. Bill Nelson and Paula Nelson 9.5/12 Minion ITC Franklin Gothic Book and Demi Everbest Printing Company

Field G u i d e s

Sharks, Rays, and Chimaeras of California, by David A. Ebert, illustrated by Mathew D. Squillante Field Guide to Beetles of California, by Arthur V. Evans and James N. Hogue Geology of the Sierra Nevada, Revised Edition, by Mary Hill Mammals of California, Revised Edition, by E.W. Jameson, Jr., and Hans J. Peeters Field Guide to Amphibians and Reptiles of the San Diego Region, by Jeffrey M. Lemm Dragonflies and Damselflies of California, by Tim Manolis Field Guide to Freshwater Fishes of California, Revised Edition, by Samuel M. McGinnis, illustrated by Doris Alcorn Field Guide to Owls of California and the West, by Hans J. Peeters Raptors of California, by Hans J. Peeters and Pam Peeters Field Guide to Plant Galls of California and Other Western States, by Ron Russo Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, by Arthur M. Shapiro, illustrated by Tim Manolis Geology of the San Francisco Bay Region, by Doris Sloan Trees and Shrubs of California, by John D. Stuart and John O. Sawyer Pests of the Native California Conifers, by David L. Wood, Thomas W. Koerber, Robert F. Scharpf, and Andrew J. Storer introductory Guides

Introduction Introduction Introduction Introduction Hogue

to Air in California, by David Carle to Fire in California, by David Carle to Water in California, by David Carle to California Beetles, by Arthur V. Evans and James N.

Introduction to California Birdlife, by Jules Evens and Ian C. Tait Weather of the San Francisco Bay Region, Second Edition, by Harold Gilliam Introduction to Trees of the San Francisco Bay Region, by Glenn Keator Introduction to California Soils and Plants: Serpentine, Vernal Pools, and Other Geobotanical Wonders, by Arthur R. Kruckeberg Introduction to Birds of the Southern California Coast, by Joan Easton Lentz

Introduction to California Mountain Wildflowers, Revised Edition, by Philip A. Munz, edited by Dianne Lake and Phyllis M. Faber Introduction to California Spring Wildflowers of the Foothills, Valleys, and Coast, Revised Edition, by Philip A. Munz, edited by Dianne Lake and Phyllis M. Faber Introduction to Shore Wildflowers of California, Oregon, and Washington, Revised Edition, by Philip A. Munz, edited by Dianne Lake and Phyllis Faber Introduction to California Desert Wildflowers, Revised Edition, by Philip A. Munz, edited by Diane L. Renshaw and Phyllis M. Faber Introduction to California Plant Life, Revised Edition, by Robert Ornduff, Phyllis M. Faber, and Todd Keeler-Wolf Introduction to California Chaparral, by Ronald D. Quinn and Sterling C. Keeley, with line drawings by Marianne Wallace Introduction to the Plant Life of Southern California: Coast to Foothills, by Philip W. Rundel and Robert Gustafson Introduction to Horned Lizards of North America, by Wade C. Sherbrooke Introduction to the California Condor, by Noel F. R. Snyder and Helen A. Snyder ¡Regional G u i d e s

Natural History of the Point Reyes Peninsula, by Jules Evens Sierra Nevada Natural History, Revised Edition, by Tracy I. Storer, Robert L. Usinger, and David Lukas