A Flora of Southern California [Reprint 2020 ed.] 9780520338654

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A F L O R A OF S O U T H E R N

CALIFORNIA

stigma — style — anther „ - filament

, sepal

rfLrfc erf a ^JCymr

stigma, style & o v a r j = pistil anther & filament = stamen petals taken together - corolla sepals taken t o g e t h e r = c a l j x

FLORA OF SOUTHERN CALIFORNIA P H I L I P A. M U N Z DIRECTOR EMERITUS RANCHO SANTA ANA BOTANIC GARDEN CLAREMONT, CALIFORNIA

U N I V E R S I T Y OF C A L I F O R N I A PRESS BERKELEY, LOS ANGELES, LONDON

UNIVERSITY OF CALIFORNIA PRESS BERKELEY AND LOS ANGELES, CALIFORNIA UNIVERSITY OF CALIFORNIA PRESS, LTD. LONDON, ENGLAND COPYRIGHT ® 1974, BY THE REGENTS OF THE UNIVERSITY OF CALIFORNIA ISBN-0-520-02146-0 LIBRARY OF CONGRESS CATALOG CARD NUMBER: 7 3 - 1 7 4 4 6 2 PRINTED IN THE UNITED STATES OF AMERICA

To the Memory of SUSANNA BIXBY B R Y A N T this book is respectfully dedicated. Loyal daughter of California, lover of its out-ofdoors and its vegetation, and creator of the R a n c h o Santa Ana Botanic Garden.

CONTENTS INTRODUCTION

1

BOUNDARIES

1

CLIMATE

1

THE VEGETATION

1

P L A N T DISTRIBUTION

5

GEOLOGICAL HISTORY

6

INSULAR F L O R A

6

DISCONTINUOUS D I S T R I B U T I O N

7

SUMMARY

7

ACKNOWLEDGMENTS

7

ABBREVIATIONS

8

CLASSIFICATION OF SOUTHERN CALIFORNIA VASCULAR PLANTS

11

K E Y TO M A J O R GROUPS

11

SUBDIVISION LYCOPSIDA

11

SUBDIVISION SPHENOPSIDA

15

SUBDIVISION P T E R O P S I D A

16

CLASS FILICAE

16

CLASS CONIFERAE

35

CLASS GNETAE

43

CLASS ANGIOSPERMAE

45

SUBCLASS DICOTYLEDONES SUBCLASS MONOCOTYLEDONES

45 862

ADDITIONS AND CORRECTIONS

1017

GLOSSARY

1019

INDEX

1033

INTRODUCTION BOUNDARIES The area designated as southern California in this book extends from its northern boundary of Point Conception, Santa Barbara County, eastward along the crest of the Santa Ynez Mountains to the Mt. Pinos region in Ventura County, Fort Tejon in Kern County, the Tehachapi and Piute mountains, then northward to Little Lake in Inyo County and along the east slopes of the Inyo and White mountains to the Deep Springs region. It does not cover the northern part of Santa Barbara County, the southern end of the San Joaquin Valley, nor any of the Owens Valley, since each of those areas includes many elements of a more northern flora. As here defined, southern California comprises a cismontane area between the sea and the mountains, a montane area which in some cases reaches considerable elevation (Mt. Pinos, San Gabriel, San Bernardino, San Jacinto, Santa Rosa, Palomar, Cuyamaca and Laguna ranges), and a transmontane or desert area which is constituted largely of the Mojave and Colorado deserts. A fourth area consists of the islands off the coast: a northern group or Channel Islands (San Miguel, Santa Rosa, Santa Cruz and Anacapa islands) and a southern group (Santa Catalina, San Clemente, Santa Barbara and San Nicolas islands).

CLIMATE (Sprague, M., Climate of California, U.S. Yearbook of Agriculture 1941: 783-797.) Owing to the wide range of topography and the influence of coast and mountains, there are several unlike climates, marked differences in temperatures and precipitation occurring within a very few miles. T h e major factor in temperature is the isotherms that tend to follow topographic contours. The immediate coast tends to be cool and without the extreme fluctuation in temperature found in inland valleys and deserts with a more continental climate. Most of the region has a wet and a dry season, the cooler months usually the wetter. In the montane region snow falls mostly above 5000 ft., and many days have frost, which is rare at the extreme coast. Average annual precipitation tends to increase with altitude, varying from less than 2 inches in Death Valley to perhaps 50 in the wettest parts of the mountains. In such an arid climate torrential rains may cause much washing. Proximity to the coast, and fog, are important elements moderating the climate.

THE VEGETATION In a climate like those described above, with a long dry season and rather mild winters, our typical "California vegetation" is largely Mediterranean in type, with harsh-leaved evergreens (sclerophylls) that are ± woody and with herbs in between. The brushy types are often spoken of as chaparral. Where the rainfall is greater, arborescent types occur and we get woodland, then at still higher elevations which are cooler and wetter, we generally pass into coniferous vegetation orforests. Beginning at the coast, the principal Plant Communities are as follows: (1) Coastal Strand. Sandy beaches and dunes, with many succulent plants. Rainfall running from 10 to 25 inches; temperature rather even; little or no frost. Characteristic genera: Abronia, herbaceous species of Atriplex, Camissonia, Convolvulus. (2) Coastal Salt Marsh. Tidelands, etc., with wet saline places and same climate as in 1. Much succulence. Distichlis; chenopods like Suaeda, Salicornia; Limonium. (3) Freshwater Marsh. At various elevations mostly below 500 ft., in wet or semi dry places, with varying climates, but wet substratum. Typha, Scirpus, Eleocharis.

[1]

4

Introduction

(4) C o a s t a l Sage S c r u b . Half-woody shrubs; cismontane from the coast to ca. 3000 ft. Precipitation 10-20 inches, usually not much frost. Artemisia, various species of Salvia, Eriogonumfasciculatum, Haplopappus species. (5) C h a p a r r a l . Woodier shrubs, with well-developed broad-leaved sclerophylls; partly developed in the past by fire a n d many species are stump-sprouters after fire. Rainfall 14-25 inches, winters cooler; from above Coastal Sage Scrub to Yellow Pine Forest; cismontane. Heteromeles, Adenostoma, Cercocarpus, Arctostaphylos, shrubby Quercus, Ceanothus, R h a m n u s . (6) V a l l e y G r a s s l a n d . Coastal hot interior valleys below 4000 ft.; rainfall 6 - 2 0 inches, mixed in with the two preceding communities, but often on the south-facing slopes. M a n y wildflowers, including Ranunculus a n d Delphinium; originally largely perennial bunch-grasses, now largely weedy annual introduced grasses. (7) S o u t h e r n O a k W o o d l a n d . O p e n woodland, with ca. 15-25 inches of rain; oaks, walnut, sycamore, elderberry, sugar bush. Northward running into the woodland of the Sierran foothills a n d the Coast Ranges west of the San J o a q u i n Valley. (8) M o n t a n e C o n i f e r o u s F o r e s t . In California as a whole this community is divisible into a lower one (Yellow Pine Forest), then a layer (Red Fir Forest) with more snow, cooler weather a n d somewhat different species of trees. However, in our southern mountains with a comparatively small area at these higher altitudes as compared to the much larger one in the Sierra Nevada, these communities are somewhat telescoped, a n d I a m not attempting a division between about 5000 a n d 9000 ft. Precipitation runs from perhaps 35-50 or to 60 inches a n d growing season from 3 to 6 or 7 months. Pintts ponderosa, P.jeffreyi, Abies concolor, P. coulteri, Calocedrus decurrens, Quercus kelloggii, various species of Arctostaphylos a n d Ceanothus a n d of Cercocarpus are abundant. In its upper parts Pinus murrayana is found. Above 9500 ft. in a few places, such as in the San Bernardino M o u n tains, there are more Limber Pine (P.Jiexiiis) a n d Lodgepole, a poor representation of the so-called Subalpine Forest of the Sierra but without Whitebark Pine or Hemlock. (9) Bristle-cone P i n e F o r e s t . O n the upper parts of the higher mountains of the northern Mojave Desert (Panamint, Inyo a n d White mountains), mostly above 8000 ft. a n d with perhaps 15-20 inches annual precipitation. T h e dominant tree is Pinus longaeva (Bristle-cone) a n d such shrubs as Cercocarpus ledifolius, Chrysothamnus and Artemisia nova. (10) S a g e b r u s h S c r u b . Descending toward the desert from Bristle-cone Pine a n d even at its elevation, on drier more exposed slopes, are great expanses of low gray species of woody Artemisia (A. carta, A. nova, a n d farther down, A. tridentata), with Rabbit-Brush (Chrysothamnus), Coleogyne a n d Purshia. Average precipitation 8 - 1 5 inches; elevations, 4000-9000 ft. (11) S h a d s c a l e S c r u b . I n heavy soil, often with underlying hardpan, and at about 3000-6000 ft. is another low shrubby vegetation, with perhaps 6-15 inches of rain and often near Joshua Tree Woodland, but apparently with different soils. Largely in the extreme northern Mojave Desert, it includes such species as Atriplex confertifolia, Grayia spinosa, Eurotia lanata, Artemisia spinescens, Menodora spinescens, Gutierrezia sarothrae, Coleogyne ramosissima. Pinyon-Juniper Woodland a n d J o s h u a Tree Woodland have about the same climatic conditions as the two preceding communities, but often granitic and less saline soils. (12) P i n y o n - J u n i p e r W o o d l a n d . Includes Pinyon (Pinus monophylla), J u n i p e r (Juniperus califomica or J. osteosperma), Scrub Oak (Quercus turbinella), Yucca schidigera, etc. I t occurs commonly at 5000-8000 ft., receives 12-20 inches of precipitation, with some snow. Shrubs are Purshia, Cowania, Fallugia, Cercocarpus. (13) J o s h u a T r e e W o o d l a n d . At 2500-4000 ft., with 6 - 1 5 inches of rain, partly as summer showers, extends from extreme west to extreme east of the Mojave Desert. Yucca brevifolia, Y. schidigera, Salazaria, Lycium, Salvia, Eriogonum. (14) C r e o s o t e B u s h S c r u b . T h e great mass of the floor of the deserts a n d their lower slopes are covered by a scrub vegetation of Larrea or Creosote Bush. Rainfall 2 - 8 inches, partly in summer. Burr weed (Ambrosia dumosa), Ocotillo (Fouquieria), Incienso (Encelia), etc.

5

Plant Distribution

(15) Alkali Sink. A term used for alkaline flats a n d low places with no or poor drainage, largely at the elevations of the Creosote Bush, i.e., below 4000 ft. T h e plants are largely fleshy halophytes (Allenrolfea, Salicornia, Atriplex, Suaeda, with Salt Grass (Distichlis) and Mesquite (Prosopis) a n d some introduced plants like Tamarisk. These Plant Communities are useful since they indicate for a given species something as to its plant associates a n d its ecology (altitudes, rainfall, etc.), a n d thus often enable a student to be more certain that he has identified a plant correctly. Plant Communities are often rather indefinable; for example, sometimes a north-facing slope holds its moisture longer than the hotter south side opposite it a n d accommodates a different lot of plants, such as chaparral on the north-facing slope and coastal sage scrub on the south. Naturally where the two meet there is confusion. This can be true also as the result of burning, deforestation, agriculture. After a given plant cover has been badly despoiled, it becomes weedy and may recover something of its earlier nature only after many years.

PLANT DISTRIBUTION O n e cannot be long in southern California and observe its vegetation without being impressed by certain distribution patterns, for example, the likeness of the Pine belt to the Sierra Nevada. There is a series of "stepping stones" between the southern Sierra and our more southern mountains, notably the Tehachapi Mountains, Mt. Pinos region (8826 ft.), Sawmill and Liebre mountains, then the San Gabriel Mountains (10,080), San Bernardino Range (nearly 11,500 ft.), San Jacinto Mountains (ca. 10,800 ft.), Santa Rosa Mountains (8716 ft.), Palomar Mountains (6126 ft.), Cuyamaca Mountains (6515 ft.), a n d Laguna Mountains (over 5000 ft.). W i t h so many high spots in a more or less broken series, it is not surprising to find that a large portion of the plant species of the pine belt have a Sierran affinity, with perhaps 100 such species as far south as the mountains of San Diego County a n d many more in the San Jacinto a n d San Bernardino mountains, in meadows a n d cool areas. Furthermore, the southern climate was formerly much cooler than now. There were cirques a n d glacial moraines in the San Bernardino Mountains, where now little or no snow persists until August. I n the same way marked distribution patterns exist at lower elevations. There is similarity between the Mojave Desert a n d Great Basin; many species in the eastern Mojave of California extend into U t a h , the Colorado Desert a n d northwestern Mexico, often combining in the Sonoran Desert with quite a different makeup from the Mojave, such as trees like Olneya a n d Cercidium, of a thorny forest type. O u r cismontane region is in many ways the typical "California" flora, having the sclerophyll or broad-leaved evergreen groups which often arose in the highlands of Mexico. These migrated north in a time more moist than now, then west to the coast, but since have been cut off from their Mexican relatives by the intervening deserts. Examples are manzanitas (Arctostaphylos), Fremontodendron, Ceanothus, evergreen oaks and Cupressus. O n e would expect much similarity between our higher mountains (including the Sierra Nevada) a n d the Rocky Mountains, but this is not so great as it might be. Undoubtedly the summer dryness of our area as compared with that of the Rocky Mountains means that m a n y northern plants, which in m a n y cases are circumpolar a n d have worked their way south, have disappeared in our dry region a n d have survived in the Rockies with more summer rain. Of course, some species, like species of Juncus, a n d plants that grow in mountain meadows, have survived. A rather unexpected phenomenon is the presence in our area of such Eurasian genera as Aquilegia, Anemone, Delphinium a n d Crepis. Some that have been carefully monographed originated deep in Asia a n d radiated out from there to Europe, northern Africa, a n d North America, by way of what is now the Bering Strait.

Introduction

6

GEOLOGICAL HISTORY Eocene. Seventy million or more years ago, there were three major vegetation units in North America: (1) Neotropical Tertiary extended north to southeastern Alaska and to Canada. The climate was uniformly warm, with a rainfall of 80 inches or more. This unit included many broad-leaved evergreens of tropical families such as Cinnamomum, Cycas, Persea (avocado) and Sabal. As yet there were no extensive mountain ranges. (2) Arcto-Tertiary was a northern unit during the Eocene period and comprised Abies, Acer, Alnus, Chamaecyparis, Cornus, Lithocarpus, Picea, Populus, relatives of Sequoia and Thuja. Many of these are still here, but more of them, especially broad-leaved and often deciduous species, have persisted in our wetter eastern climate. (3) Madro-Tertiary (named for Sierra Madre of Mexico) originated in southwestern North America. Smaller-leaved drought-resistant sclerophylls existed by Middle Eocene and spread with increasing dryness. Example: Arbutus, Juglans, some pines (Pinyon, Digger), Quercus (live oaks), Lyonothamnus, Umbellularia, Cupressus, certain species of Prunus, Cercocarpus, Purshia. Later than Eocene. Elevation of mountain ranges and their accompanying rainshadows and development of drier summers; development of deserts. Tropical flora pushed south. Many genera migrated to the coast. A montane-coniferous forest developed and invaded higher mountains in late Miocene and in Pliocene; it reached southern California in Pleistocene and persisted as our pine belt, so that some 325 such species are found in the San Bernardino Mountains. The Madro-Tertiary contributed largely to our California Woodland element such as the digger-pine woodland, oak-walnut woodland, and to our pinyon-juniper woodland. Chaparral ancestry is quite old (manzanita, Ceanothus, Cercocarpus, Dendromecon, Fremontodendron) and was restricted to cismontane California in late Pliocene. Pleistocene. Temperate vegetation showed further advancement southward than at any other time, the redwood reaching Carpenteria in Santa Barbara County. The climate was cooler and more moist than now. Death Valley was a lake 90 miles long and 600 feet deep. With glaciation in some of our mountains, the pine belt plants came far south; later with more modern warmth and dryness, many were pushed north or survived here and there as relicts (example, Male Fern in Holcomb Valley, found once in the 1880s; Anaphalis margaritacea in a single canyon in the San Bernardino Mountains). Present. At present we have a mixture of genera and species of northern ancestry: Artemisia tridentata, Salsola, many grasses, Chrysothamnus, Eurotia, Aquilegia, Delphinium, Crepis; some of these are from the old Arcto-Tertiary origin and include many circumpolar species: ferns, grasses, sedges, etc. We also have plants of southern derivation, often comingdown from Madro-Tertiary sources: Larrea, Fremontodendron, Eriogonum, Grayia. The third big element is of local derivation (especially true of species) and represents much endemism. Local endemics (correlated with tremendous variation in topography and climate, summer dryness, etc.) may occur: (a) mountain range by mountain range (Sedum niveum, Lesquerella bernardina, Arabis parishii, Horkelia wilderae, Sidalcea pedata, Taraxacum californicum); (b) valley by valley (Ribes hesperium, Ribes parishii, Lathyrus laetiflorus, Collinsia parryi, Calochortus plummerae). Others are general southern California endemics : Matilija Poppy, Eriogonum species, Adenostoma sparsifolium, Forbes cypress, Lathyrus species. Another large group is island endemics, some rather general, others confined to one or few islands: Salvia brandegei, Eriogonum giganteum, E. arborescens, Lyonothamnus, Ceanothus arboreus. INSULAR FLORA For a discussion of our insular flora see R. Thome, The California Islands, Ann. Mo. Bot. Gard. 56: 391-408, 1969. The chain of islands off the southern California coast represents, at least in part, the westerly extension of the Santa Monica Mountains. Plants from the mainland migrated west and had almost disappeared from the mainland by the

7

Insular Flora

end of the Pliocene. Speciation developed when the offshore lands broke up into further separate islands. Two general groups are a northern group (Santa Rosa, Santa Cruz, San Miguel, Anac a p a ) with pines, Quercus tomenlella, Rhamnus pirifalius, Ceanothus arboreus, Prunus lyonii, a n d

a southern group (San Nicolas, Santa Barbara, Santa Catalina and San Clemente) lacki n g pines, b u t h a v i n g L y o n o t h a m n u s , Quercus tomentella, Rhamnus pirifolia,

Prunus

lyonii,

Ceanothus arboreus. Raven says that there are 76 endemic taxa on the islands, 23 in the northern group, 38 in the southern group, and 15 common to both groups (P. Raven, The floristics of the California Islands in R. N. Philbrick (ed.), Proceedings of the Symposium on the Biology of the California Islands, p. 63, 1967 [published by Santa Barbara Botanic Garden]). San Clemente Island has several species restricted otherwise to Guadalupe Island : Phaceliafloribunda,Camissonia guadalupensis. Other Guadalupe Island species occur on b o t h C a t a l i n a a n d S a n C l e m e n t e : Scrophularia villosa, Galvesia speciosa, Crossosoma californica.

DISCONTINUOUS DISTRIBUTION Some striking cases probably represent relict distribution, with certain areas maintaining old species because of special soil and precipitation factors, for example species in the mountains of San Diego County and cismontane central California: Thermopsis califomica as v a r . semota, Viola lobata ( S a n t a L u c i a M o u n t a i n s n o r t h ) , Ceanothusfoliosus as C. austromontanus in region a b o u t J u l i a n ; Salvia sonomensis; ^igadenus venenosus, Downingia concolor as var. brevior.

California (largely cismontane) with the other states of our west coast and extreme southern South America have over 100 species closely related or perhaps identical: Phacelia magellanica group, Gilia, Larrea, Prosopis, Apiaceae like Bowlesia incana, Sanicula crassicaulis and S. graveolens. So far, sporadic long-distance transtropical dispersal seems to be a hypothesis for explanation of this discontinuity; most such species are self-compatible so that a single introduction might suffice.

SUMMARY The geographic area here called southern California, with perhaps an extent of 30,000 square miles, ranges from below sea level in Death Valley and Sal ton Sea to over 11,000 ft. in the San Bernardino Mountains. It has an annual precipitation from about one inch to perhaps 50 inches. The flora has had a long history, with northern, Mexican and at first tropical elements early represented; with later an increasing elevation of mountains and diversity of topography accompanied by a drying process and by rain-shadows. T h e elements from the various ancient floras have been highly modified. With the Pleistocene came a great migration southward, thus taxa from various areas met for the first time, allowing much hydridization. In the Rancho Santa Ana Botanic Garden this same situation has occurred as species from various parts of the state have for the first time been brought to grow near each other; so much hybridization has occurred that for genera like Ceanothus, seeds harvested in the Garden cannot be used to represent the species with any certainty. Thus in nature new forms arose and found various ecological niches. Many species moved north again or to higher altitudes as the more recent drier and warmer climate evolved. The result is that now we have a very complex flora with many not very ancient species. It is characterized by many large genera: Eriogonum, Lupinus, Astragalus, Penstemon, Trifolium, Cryptantha, Phacelia, Mimulus, Lotus, Gilia.

ACKNOWLEDGMENTS In compiling a manual of the plants of any region, the author naturally must, in addition to the study of plant specimens themselves, turn to recently published works for changes in concept and literature. For the most part I cite such references used herein immediately after the generic description or sometimes briefly in a discussion of a given species.

8

Introduction

Then too, one finds it helpful to consult friends who may be specialists or students of various groups and get from them opinions not yet published. In this particular I have depended primarily on Robert Thorne, first for his concept of groups above families and of families themselves and for the names he employs, although I have not always followed his usage. I have also profited greatly by his knowledge of certain aquatics, as well as of sedges, grasses, etc. and of certain geographical areas such as Santa Catalina Island and San Gabriel Mountains. I have had help from Lee W. Lenz particularly with the Brodiaea complex, from Lyman Benson with Cactaceae, from James Henrickson with Fouquieria and other plants, from his former student Dieter H. Wilken with Baccharis viminea and the genus Hulsea, from James Reveal with that ever-puzzling genus Eriogonum. Others to whom I have turned are Stephen Tillett on Abronia, Alva Day in Gilia, J o h n Tucker in Quercus, Reid Moran in Crassulaceae and plants of Lower California, especially those of Guadalupe Island, Reed Rollins in Brassicaceae, Wallace Ernst in Papaveraceae, and Dr. Wahl's determinations of Chenopodium as left in our herbarium. Still others who have contributed largely are J o h n Thomas Howell, Ernest Twisselmann, and Percy C. Everett. Harry Thompson and Joyce Roberts have kindly prepared the manuscript for Loasaceae. Lawrence Heckard has loaned me notes on Orobanche; he and Rimo Bacigalupi have helped with Castilleja. Ella May Dempster has loaned me unpublished manuscript on Galium, A. Michael Powell on Laphamia and Perityle, Delbert Wiens on Arceuthobium and prepared a key for the southern California species of the genus. David Dunn has sent notes on Lupinus. Others who have been particularly helpful with specimens, often showing new distribution records or exemplifying new taxa, have been Tom C. Fuller, Ernest Twisselmann, R. W. Townsend, Louis B. Ziegler, John and Lucille Roos, Janice Beatley. I especially wish to express my gratitude to my wife Alice M. Munz for her many hours spent on mounting drawings that make up the plates illustrating over 600 species. The illustrations in the book represent the work of several persons. Those unsigned are largely the work of Stephen Tillett, with a few, such as for orchids, by Richard Shaw. O n those signed, the letter J means Jeanne Janish, who has illustrated western plant species more widely than any other artist; DB stands for Dick Beasley, at present a professor of art. Both of these artists have an unusual ability to throw into three dimensions a flattened specimen mounted on an herbarium sheet. The other drawings were largely by former students: R C or Cross by the late Rodman Cross, Craig by the late Tom Craig, Z by Milford Zornes, SHL by Shue-Huei Liao, a student from Taiwan. I am grateful to Art Gibson in helping prepare some of the last pages of manuscript.

ABBREVIATIONS acc.-according to adv.-adventive Afr.-Africa ak., aks.-akene, akenes Alta.-Alberta Am.-America, American Ariz. — Arizona Ark.-Arkansas auth.-authors B.C.—British Columbia C.-Canyon ca.-circa (about or approximately) Calif. - California Can.-Canada caps.-capsule cent.-central

cm.-centimeter, centimeters co.-county, counties Colo. - Colorado cult.-cultivated, cultivation diam. -diameter dm.—decimeter, decimeters e.-east, eastward, eastern elev., elevs.-elevation, elevations Eu.-Europe F.-forest f.-forma fil., fils.-filament, filaments fl., fls.-flower, flowers Fla.-Florida fid.-flowered fr., frs.-fruit, fruits

Abbreviations

9

f t . - f o o t , feet hemis. - hemisphere id., ids.-island, islands Ida.-Idaho 111.-Illinois Ind.—Indiana infl., infls.-inflorescence, inflorescences introd.-introduction, introduced invol., invols.-involucre, involucres Kans.-Kansas Ky.-Kentucky La. -Louisiana L. Calif.-Lower California If.-leaf lft., lfts.-leaflet, leaflets loc., Iocs.-locality, localities lvd.-leaved lvs.- leaves m . - meter, meters M a n . - Manitoba Medit. - Mediterranean M e x . - Mexico, Mexican Mich. - Michigan Minn. - Minnesota Miss. - Mississippi mm.-millimeter, millimeters Mont. - Montana mt., m t s . - m o u n t a i n , mountains n . - n o r t h , nothern, northward N. A m . - N o r t h America, North American nat.-native natur. - naturalized N. D a k . - N o r t h Dakota ne.-northeast, northeastern

n. M e x . - n o r t h e r n Mexico Nebr. - N e b r a s k a Nev.-Nevada New M e x . - N e w Mexico Nfld. - Newfoundland no.-number n w . - n o r t h west, northwestern Okla. - Oklahoma Ore. - Oregon R.-river ref., refs.-reference, references s.-south, southern, southward S. A m . - S o u t h America Sask. - Saskatchewan S. D a k . - S o u t h Dakota se.-southeast, southeastern segm., segms.-segment, segments Son.-Sonora sp., spp.-species (singular a n d plural) ssp., sspp.-subspecies (singular a n d plural) sw.-southwest, southwestern temp. - temperate Tex.-Texas trop.-tropical, tropics U . S . - U n i t e d States V. -valley Va.-Virginia var., vars.-variety, varieties w . - w e s t , western, westward Wash. - Washington wd., wds.-woodland, woodlands W . I . - W e s t Indies Wis. - Wisconsin Wyo. - Wyoming

SIGNS USED + S $ x ¡1

-

more or less staminate pistillate sign of hybrid, used before the species n a m e micron, the millionth part of a meter

NOTE TO THE READER In a book where one group has to come after another in a linear series, it is practically impossible to reveal relationship or a true phylogeny. For that reason and for convenience, I have simply used an alphabetic arrangement for families within major groups such as dicotyledons, genera within families, and species within genera. The reader may notice that in many instances word divisions at the ends of lines do not follow common American practice. This is due partly to the fact that the book was printed in England and partly to restrictions of line justification.

VASCULAR PLANTS OF SOUTHERN CALIFORNIA

Division TRACHEOPHYTA KEY TO MAJOR GROUPS 1. Plants without seeds or fls., reproducing by 1-celled spores borne in sporangia. 2. Plants not fernlike and not free-floating, the lvs. mostly minute or + scalelike (except in Jsoetes), 1-veined; the fertile lvs. with 1 sporangium on the adaxial surface. 3. Stems not jointed; lvs. not whorled and not forming a sheath at the nodes Subdivision I. Lycopsida p. 3. Steins of hollow joints; lvs. whorled and forming a sheath at the solid nodes Subdivision II. Sphenopsida p. 2. Plants fernlike and with large lvs. (fronds) or free-floating aquatics and with small or scalelike overlapping lvs.; mostly elaborately veined; sporangia of spreading lvs. usually abaxial Subdivision I I I . Pteropsida Class I . Filicae p. 1. Plants with seeds usually produced by cones or fls. 4. Seeds not inclosed in ripened pistils, but naked and usually borne on the surface of a scale; the crowded or overlapping scales usually forming a cone or strobilus; plants not bearing typical fls. 5. Stems not jointed; lvs. needlelike or linear, sometimes scalelike and then closely overlapping; plants mostly with resin. Mostly trees or arborescent Class II. Coniferae p. 5. Stems jointed; lvs. scalelike, in 2's or 3's in widely separated whorls; plants without resin; cones small, with thin scales. Desert shrubs . . . . Class I I I . Gnetae p. 4. Seeds inclosed in ripened pistils; plants producing true fls. . Class IV. Angiospermae p. 5a. Cotyledons 2; stems usually exogenous (increasing in diam. by cambial activity between the xylem and phloem); lvs. mostly net-veined; fls. usually on the plan of 4 or 5 Subclass I. Dicotyledones p. 5a. Cotyledon 1; stem mostly endogenous, or if with cambial activity, this adding whole vascular bundles; lvs. mostly parallel-veined; fls. mostly on the plan of 3 Subclass I I . Monocotyledons p.

11 15 16

35 43 45 45 862

Subdivision I. LYCOPSIDA Class LYCOPODIAE P l a n t - b o d y a sporophyte w i t h slender stems a n d roots a n d small mostly spiral or p a i r e d or w h o r l e d 1-veined lvs. or w i t h cormlike s t e m a n d longer lvs. S p o r a n g i u m solitary o n t h e a d a x i a l face a n d n e a r t h e base of t h e s p o r a n g i u m - b e a r i n g If. (sporophyll); sporophylls often segregated f r o m t h e sterile foliage lvs. a n d a g g r e g a t e d i n t o + loose strobili. Spores developing i n t o m i n u t e or microscopic g a m e t o p h y t e s p r o d u c i n g a n t h e r i d i a a n d a r c h e gonia, t h e (J a n d $ sex-organs. Fusion of g a m e t e s results in a n e w s p o r o p h y t e . KEY T O ORDERS Stems above ground, + elongate and branched, covered with many minute overlapping scalelike lvs. less than 1 cm. long 2. Selaginellales Stems underground, cormlike, bearing tufted lvs. 2.5-25 cm. long 1. Isoetales

[11]

12

Isoetaceae

Order 1. ISOETALES Characters as given for the family Isoetaceae 1.

Isoetaceae.

QUILLWORT FAMILY

Small, aquatic, amphibious or terrestrial herbs, with a 2-3-lobed corm crowned with many sedgelike elongate-subulate lvs. with large basal sporangia. Sporangia solitary, on upper surface of If.-base, of 2 kinds: micro- and macro-sporangia, the former producing many small spores each of which forms an antheridium, the latter with large spores forming $ gametophytes. One genus of worldwide distribution. 1 . Jsoetes L . QUILLWORT Corm fleshy, bearing roots below. Lvs. with an upper part that is sterile and septate, with 4 longitudinal series of air-spaces and with or without peripheral strands, with or without stomates. Lvs. also with a fertile basal part forming a large plano-convex imbedded sporangium partly covered apically by a thin membrane (velum) above which is a small green triangular structure (ligule). Ca. 60 spp. (Greek, isos, ever, and etas, green, of uncertain application.)

Plants mostly entirely submersed; lvs. lacking peripheral strands; stomata few or lacking; corm usually 2-lobed 1. I. bolanderi Plants terrestrial or amphibious, on wet soil or about margins of ponds or streams; stomata numerous. Corm usually 2-lobed; velum not completely covering the sporangium 2. /. howellii Corm usually 3-lobed; velum usually nearly or quite covering the sporangium . . 3. /. orcuttii 1. I. bolanderi Engelm. [I. califomica Engelm.] Plate 1, Fig. A. Submersed; corm deeply 2-lobed; lvs. 6-25, tapering to a very fine point, bright green, soft, 6-15 (-25) cm. long, with some stomates but usually no peripheral strands; ligule small, cordate; sporangia 3—i mm. long, ca. J covered by the velum; macrospores ca. 0.3-0.4 mm. in diam., with low tubercles.—Mountain lakes and ponds, 5000-11,000 ft.; Montane Coniferous F.; San Bernardino Mountains, Sierra Nevada to Wash., Rocky Mountains. 2. I. howellii Engelm. [/. melanopoda var. calif omica A. A. Eat.] Amphibious; corm 2-lobed; lvs. mostly 10-30, bright green, spreading, 5-28 cm. long, with many stomates and usually 4 peripheral strands; ligule narrow, elongate-triangular; velum covering J of the sporangium; macrospores white (tan when wet), 0.25-0.6 mm. in diam., usually with tubercles and anastomosing and distinct crests.—In water and on mud, below 9000 ft.; many Plant Communities; mesas near San Diego to San Bernardino Mts. and Mirror Lake, Ventura Co.; to Sierra Nevada and Wash., Mont. 3. I. orcuttii A. A. Eat. [/. nuttalliivar. o. Clute.] Corm 3-lobed; lvs. 3-25, spreading, 3-6 cm. long, with many stomates and no peripheral strands; velum complete; ligule small, triangular; macrospores gray (or brown when wet), 0.2-0.4 mm. in diam., smooth, glossy, sometimes ± tubercled.—In water of vernal pools and on mud, at low elevs.; Chaparral, V. Grassland, etc.; San Diego Co. to cent. Calif.

Order 2. SELAGINELLALES Characters as given for the family

Selaginellaceae

Family 1. Selaginellaceae Low terrestrial plants, freely branched, with numerous very small, usually imbricate lvs. that are spirally arranged and all alike or in 4 longitudinal rows and of 2 kinds. Sporangia in terminal quadrangular sessile spikes or strobili of slightly modified lvs. (sporo-

Plate 1. Fig. A, Isoeies bolanderi, adaxial view of separate If. with basal s p o r a n g i u m , partial velum, t r i a n g u l a r ligule. Fig. B, Selaginella bigelovii, s e p a r a t e strobilus, smooth m i c r o s p o r a n g i u m , lobed m a c r o s p o r a n g i u m . Fig. C , Equisetum arvense, early fertile stem a n d later b r a n c h e d sterile stem. Fig. D , Equisetum laevigatum, cones on vegetative stem. Fig. E, Athyriumfilix-jemina, elongate indusia. Fig. F, Cystopteris Jragilis, r o u n d e d sori.

14

Selaginellaceae

phylls), each strobilus containing both microsporophylls a n d macrosporophylls, the former with m a n y minute reddish or orange microspores, the latter with 1 - 4 rather large macrospores. O n e genus.

1.

Selaginella Beauv.

SPIKE-MOSS. LITTLE

CLUB-MOSS

Characters of the family. Ca. 600 spp., widely distributed, especially in the tropics. (Name, a diminutive of Selago, a classical n a m e for some sp. of Lycopodium.) (Tryon, R. M. S. S. rupestris and its allies. Ann. Mo. Bot. Gard. 42: 1-99. 1955). 1. Stems erect or ascending, rooting only at or near the base 2. S. bigelovii 1. Stems prostrate to decumbent, rooting at or near the apex. 2. Lvs. on the under side of the main stems not decurrent, lacking a terminal seta; stems forming an ashy carpet-like growth very near the ground. San Diego region 3. S. cinerascens 2. Lvs. on the under side of the main stems strongly decurrent. 3. Lvs. lacking a terminal seta at maturity; plants strongly dorsi-ventral. Desert 4. S. eremophila 3. Lvs. with a terminal seta; stems radially symmetrical. 4. Setae from 1/3-2/3 the length of the lf.-blade 1. S. asprella 4. Setae less than 1 /3 the length of the lf.-blade. 5. The setae yellowish, smooth; cilia 2-7 on each side of the If. or wanting. Mostly from above 7500 ft 6. S. watsonii 5. The setae white, + scabrous; cilia more numerous. Panamint and Providence Mountains, mostly from below 7500 ft 5. S. leucobryoides 1. S. asprella M a x o n . Stems loosely m a t t e d , 3 - 6 cm. long, creeping, with laxly ascending branches 1 - 2 cm. long; lvs. ascending, somewhat imbricate, deltoid-subulate, glaucous, white-margined, eciliate or ciliate near the apex, 2.8-3.2 m m . long; the setae 0.7-0.9 m m . long, white-hyaline, forming tufts at the ends of the branches; strobili lax, 1 - 2 cm. long, arcuate, the sporophylls 2.5-3 m m . long, long-acuminate.—Dry rocky places, 5000-8900 ft.; M o n t a n e Coniferous F . ; San Gabriel, San Bernardino, San Jacinto, S a n t a A n a a n d Laguna mts.; s. Sierra N e v a d a ; n. L. Calif. 2. S. bigelovii U n d e r w . Plate 1, Fig. B. Stems slender, shortly branched, ascending to erect, 5 - 2 0 cm. long, from widely creeping rhizomes; lvs. appressed-imbricate, graygreen, the blades 1.2-1.8 m m . long, ciliate, narrow-lanceolate, each with a short white seta; strobili 4 - 1 5 m m . long, erect at tips of short lateral branches, the sporophylls ovate, ca. 2 m m . long.—Dry rocky banks below 6000 ft.; C h a p a r r a l , Coastal Sage Scrub, etc.; cismontane f r o m n. L. Calif, to Sonoma Co. a n d s. Sierra Nevada. Channel Ids. 3. S. ciner&scens A. A. E a t . [5. bryoides U n d e r w . ] Plants forming a close ashen carpet on the g r o u n d ; stems wiry, mostly 5 - 1 2 cm. long, b r a n c h e d ; lvs. appressed-imbricate, ashy gray, linear to broadly subulate, ciliate, not setigerous, 1.2-1.5 m m . long, with deep dorsal groove; strobili 2 - 4 m m . long; sporophylls broadly cordate, short-acuminate, ciliate.—Dry slopes a n d mesas; Coastal Sage Scrub, C h a p a r r a l ; sw. San Diego C o . ; adjacent L. Calif. 4. S. eremophila M a x o n . [5. parishii of Calif, refs.] Plants prostrate, dorsiventral, the stems 5 - 1 2 cm. long, with spreading branches; lvs. crowded, broadly lanceolate, those of the lower side 2 m m . long, thin, acutish, not setigerous when m a t u r e , with ca. 25 cilia o n each side; lvs. of u p p e r side subveitical, 1 - 1 . 4 m m . long, with 6 - 1 2 cilia on each side; strobili many, curved, 6 - 1 0 m m . long, the sporophylls with 12-18 cilia o n each side.— Sheltered places a m o n g rocks, below 3000 ft.; Creosote Bush S c r u b ; canyons along w. edge of Colo. Desert, Chuckwalla M t s . ; Ariz., L. Calif. 5. S. leucobryoides M a x o n . Plants cushionlike, the stems 1 - 2 cm. long, readily fragmenting when dry, with thick short erect branches; lvs. uniform, appressed-imbricate, glaucous, linear-subulate, 2.5-3.2 m m . long, short-setigerous, with 8-16 cilia o n each side; strobili m a n y , 5 - 1 0 m m . long, erect; sporophylls rigidly appressed-imbricate, deltoid-ovate, ciliate a n d toothed.—Rock-cievices a n d slopes, 2000-7500 ft.; Shadscale Scrub to Pinyon-Juniper W d . ; P a n a m i n t a n d Providence mts., e. Mojave Desert.

15

Equisetum

6. S. w&tsonii Underw. Gespitose, the stems prostrate, short, 2-8 cm. long, with numerous branches 1-2 cm. long, ascending; lvs. densely appiessed-imbricate, thick, linearoblong, 2-2.4 mm. long, each with broad dorsal groove and stout smooth seta, with few or no cilia; strobili 1-2.5 cm. long, sharply quadrangular, the ovate sporophylls ciliate on basal half.—Locally frequent in dry rocky places, 7500-11,000 ft.; Montane Coniferous F., Alpine Fell-fields; Santa Rosa and San Jacinto mts. n. through the mts. to Sierra Nevada and White Mts.; to Ore., Mont., Utah.

Subdivision II. SPHENOPSIDA Class 1. EQUISETAE With a single living order (Equisetales) and family. Characters as given for that family. 1.

Equisetaceae.

HORSETAIL

FAMILY

Rushlike, often branching plants, with perennial creeping branching rhizomes rooting at the nodes. Aerial stems perennial or annual, cylindrical, fluted, simple or with whorled branches at the solid sheathed nodes, the internodes generally hollow. Sheaths made up of the united minute whorled lvs. which may be free at the tips. Surfaces of the stems overlaid with silica; stomates arranged in bands or rows in the grooves. Strobili or cones terminal, formed of whorls of stalked peltate structures around a cent, axis, each with a circle of sporangia beneath. Spores uniform, green, the outer layer forming 4 hygroscopic bands. One genus. 1. EquisUum L . HORSETAIL. SCOURING-RUSH Characters of the family. Ca. 25 spp., widely distributed. (Latin, equus, horse, and seta, bristle.) (Hauke, R. A taxonomic monograph of the genus Equisetum subgenus Hippochaete. Beihefte zur Nova Hedwigia 8: 1-123. 1963) Aerial stems all green, not dimorphous; stomates in regular rows. Sheaths much longer than broad, + funnel-shaped, green, normally with a narrow black band at the top 3. E. laevigatum Sheaths nearly or quite as broad as long, cylindrical, usually ashy with 2 black bands. 2. E. hyemale Aerial stems of 2 kinds, the fertile ones not green or branched, the sterile green and with many slender branches; stomates scattered. Sterile stems stout, generally over 3 mm. thick and 6-12 dm. tall; sheaths with 20-30 teeth. 4. E. lelmateia Sterile stems slender, generally less than 3 mm. thick and less than 6 dm. tall; sheaths with 8-12 teeth 1. E. arvense 1. E. arvinse L. COMMON HORSETAIL. Plate 1, Fig. C . Fertile stems 5-25 cm. tall, flesh-colored, soon dying, the pale sheaths with 8-12 lanceolate brownish teeth; sterile stems 1-6 dm. tall, green, 6-14-ridged, roughish, the sheaths with hyaline-margined teeth; branches slender, in dense whorls; cones lance-ovoid, 2-3 cm. long; n = ca. 108 (Manton, 1950).—Wet places below 10,000 ft., many Plant Communities; cismontane Calif., Inyo Co. to Modoc Co.; to Alaska, Labrador, Nfld., most of the U.S.; Eurasia. Many growth forms have been given names. 2. E. hyemale L. var. affine (Engelm.) A. A. Eat. [E. robustum var. affine Engelm. E. praealtum Raf. E. h. var. californicum Milde. E. h. var. robustum A. A. Eat. E. r. A. Br. ex Engelm.] Stem normally unbranched, upright, persisting for at least 2 years, 5-20 dm. tall, 4-12 mm. thick, with 16-48 ridges, these very rough with 1 or 2 rows of transverse bands of silica; sheaths but little longer than broad, cylindrical and ashy with black bands

16

Equisetaceae

a t both ends, the short teeth quite persistent; lvs. 3-4-keeled, the cent, keel plainly or faintly grooved; cones ovoid, 1 - 2 . 5 cm. long, sharply apiculate; n = ca. 108 ( M a n t o n , 1950).—Occasional as colonies in moist places below 8500 f t . ; m a n y Plant Communities; cismontane a n d m o n t a n e Calif.; to Alaska, Quebec, most of U.S. 3. E . l a e v i g a t u m A. Br. \Hippochaete I. Farw. A. funstoni A. A. E a t . E. kansanum Schaffn. E.fontinale Copel.] Plate 1, Fig. D . Aerial stems of 1 - 2 years duration, normally u n b r a n c h e d , upright, smooth, tufted, normally 2 - 8 d m . tall, smoothish to rough with crossbands of silica, 15-30-ridged; sheaths longer t h a n b r o a d , usually dilated u p w a r d , t h e lower in old stems becoming girdled with brown, 7 - 1 5 m m . long; cones brown to yellow obtuse or with a slight apiculum, containing well formed spores.—In d a m p or moist places below 8000 feet; m a n y Plant Communities; cismontane Calif., Owens V . ; to B.C., L, Calif., Ontario, Tex., Mex. 4. E . t e l m a t e i a E h r h . var. b r a u n i i Milde. [ £ . maximum L a m . ] G I A N T H O R S E T A I L . Fertile stems erect, short-lived, whitish or brownish, 2 - 6 d m . tall, smooth, with loose m e m branous sheaths 2 - 5 cm. long a n d with 20-30 teeth; sterile stems 5 - 2 5 d m . tall, 5 - 2 0 m m . thick, pale green, 20-40 ridged, the sheaths cylindrical, the teeth broadly hyaline-margined; branches solid, in dense whorls; cones stout-pedunculate, 4 - 8 cm. long; n — ca. 108 ( M a n t o n , 1950).—Occasional in swampy places a n d along streams, below 4500 ft.; several Plant Communities; cismontane Calif.; to B.C. also in Mich. E . x f e r r i s i i Clute. [E. hyemale var. affine x E. laevigatum. E. h. var. intermedium A. A. Eat.] Plants occasionally occur intermediate between spp. 1 a n d 4 a n d with sterile spores which do not shed f r o m the cones. Reported from Monterey, K e r n cos., etc.

Subdivision

III. P T E R O P S I D A .

FERNS

Class 1. FILICAE Terrestrial, sometimes epiphytic or aquatic plants, usually with evident alternation of generations. T h e sporophyte generation, the fern plant, usually differentiated into stems, roots a n d lvs. I n the homosporous ferns all or certain lvs. (sporophylls) bear the m i n u t e sporangia which produce the 1-celled spores t h a t develop into the small usually independ e n t gametophyte generation. This forms antheridia a n d archegonia a n d fertilization results in a new sporophyte. Heterosporous ferns aquatic a n d floating, or on m u d ; producing the sporangia in special structures (sporocarps) that contain micro- a n d macrosporangia and result in microscopic