ECOLOGICAL AND MORPHOLOGICAL VARIATIONS OF VAUQUELINIA CALIFORNICA (TORR.) SARG. POPULATIONS IN ARIZONA

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Authors Williams, Kenneth Buck, 1930-

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WILLIAMS, Kenneth Buck, 1930- EC0L0GICAL AND MORPHOLOGICAL VARIATIONS OF VAUQUELINIA CALIFORNICA (TORR.) SARG. POPULATIONS IN ARIZONA. "

The University of Arizona, Ph.D., 1971 Botany

1 University Microfilms, A XEROX Company, Ann Arbor, Michigan 4

THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED ECOLOGICAL AND MORPHOLOGICAL VARIATIONS OF VAUQUELINIA CALIFORNICA (TORR.) SARG. POPULATIONS IN ARIZONA

by Kenneth Buck Williams

A Dissertation Submitted to the Faculty of the DEPARTMENT OF WATERSHED MANAGEMENT In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN RANGE MANAGEMENT In the Graduate College THE UNIVERSITY OF ARIZONA

19 7 1 THE UNIVERSITY OF ARIZONA

GRADUATE COLLEGE

I hereby recommend that this dissertation prepared under my direction by Kenneth Buck Williams entitled Ecological and Morphological Variations of Vauquelinia

californica (Torr.) Sarg. Populations in Arizona be accepted as fulfilling the dissertation requirement of the degree of Doctor of Philosophy

Dissertation Director Date

After inspection of the final copy of the dissertation, the following members of the Final Examination Committee concur in its approval and recommend its acceptance:*

/r/^d L a) i_y 10 u/^fi

This approval and acceptance is contingent on the candidate's adequate performance and defense of this dissertation at the final oral examination. The inclusion of this sheet bound into the library copy of the dissertation is evidence of satisfactory performance at the final examination. STATEMENT BY AUTHOR

This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are al­ lowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manu­ script in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author.

SIGNED TO My Mother and Father Evelyn Isabell McClintock Williams and Willie Benjamin Williams who taught me perseverance

iii ACKNOWLEDGMENTS

The author acknowledges the debt owed those persons and institutions instrumental in shaping his character and * instilling in him a desire to achieve. Special thanks are extended Dr. Charles D. Bonham, major professor, and Dr. Charles T. Mason, Jr., both of whom gave generously of their time in assisting in the preparation of this paperj Dr. MasonTs assistance in the taxonomic study and that of Dr. Bonham in the ecological aspects and in the dissertation completion is gratefully acknowledged. Thanks are extended to the other members of my com­ mittee: Dr. John H. Ehrenreich, Dr. Phil R. Ogden, and Dr. Walter S. Phillips who helped and inspired me during the course of this study. Appreciation is extended to the entire staff of the Department of Range Management and to Dr. Malcolm J. Zwolinski, Mr. Ernest B. Fish, and Mr. Harvey R. Fritz. Thanks are due to Mr. Joe Dixon for his help in the field assistance; Mrs. Leona Hubbard, Assistant in Botany, itfho was of constant encouragement and a ready source of in­ formation in the herbarium; and Mrs. Caryl L. Sagar, herbarium technician.

iv Appreciation is extended to Mrs. Helen D. Showalter who offered many fine suggestions and typed the manuscript. Thanks are extended also to the Papago Indian people and the San Carlos Apache Indian people for permitting the author to do research on their lands. The cooperation given by the United States National Park Service and The University of Arizona computer center is gratefully acknowledged. Thanks are due also to Dr. Clark Stevens, Department Head of Biology, Abilene Christian College, for his encourage ment and Abilene Christian College for partial support during the latter stages of the study. Norma Jean, my wife, deserves special credit for her encouragement and understanding. I appreciate more than words can express the help and companionship of my children, Sharol and Mark, on the many field trips, and their many sacrifices that enabled me to continue this study. TABLE OF CONTENTS

Page LIST OF TABLES viii LIST OF ILLUSTRATIONS . xi ABSTRACT ' xiii INTRODUCTION 1 METHODS AND MATERIALS 7 Field Studies ..... 7 Greenhouse Studies 9 Laboratory Analyses 11 DESCRIPTION OF STUDY AREAS 14 Organ Pipe Area 16 Baboquivari Canyon Area 22 Molino Canyon Area 27 El Capitan Canyon Area 32 San Carlos Area 3& Mormon Flat Area 41 RESULTS 47 Field Studies 47 Floristics - 6$ Greenhouse Studies 7& Laboratory Analyses 90 Length of Leaves 90 Y/idth of Leaves 92 Petioles 95 Spines 95 Leaf Analyses Summary 100 Seeds 102 Herbarium Specimens Ill Species Density - 112 Association Analyses 137 DISCUSSION AND CONCLUSIONS 147

vi TABLE OF CONTENTS—Continued

Page

APPENDIX A: PTERIDOPHYTA FOUND ON AT LEAST ONE STUDY PLOT 167 APPENDIX B: SPERMATOPHYTA FOUND ON AT LEAST ONE STUDY PLOT 16S REFERENCES ' 177

\ LIST OF TABLES

Table Page 1. Mean Temperatures and Precipitation for Study Areas as Recorded at Stations 17 2. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: Organ Pipe Quadrats 3. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: Baboquivari Canyon Quadrats 59 4. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: Molino Canyon Quadrats 60 5. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: El Capitan Quadrats 61 6. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: San Carlos Quadrats 62 7. Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant: Mormon Flat Quadrats 63 Per cent Slope and Direction for Each Quadrat for Each Area 67 9. Frequency of Vauquelinia californica According to Number of Stems in Each Area 69 10. Abundance and Density of Species Recorded in All Study Areas 71 11. Species Occurring on Four or More Areas 79 12. Leaf Length Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean ... 91 13. Analysis of Variance for Leaf Length 93

viii LIST OF TABLES—Continued

Table Page 14. Leaf Width Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean . 94 15. Analysis of Variance for Leaf Width 96 16. Petiole Length Means of Each. Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean 97 17* Analysis of Variance for Leaf Petioles 9& IS. Leaf Spine Means of Each Area, Each Quadrant, Each Quadrant•within Each Area and, Grand Mean . . • 99 19» Analysis of Variance for Leaf Spines 101 20. Correlation Matrix for Leaf Data 103 21. Means and Grand Means for Seed Length, Seed Bodjr Length, Seed Wing Width, and Seed Body Width . 104 22. Analysis of Variance for Seed Length 105 23 • Analysis of Variance for Seed Body Length 107 24• Analysis of Variance for Seed Wing Width 10$ 25• Analysis of Variance for Seed Width ...... 109 26. Correlation Matrix for Seed Data 110 27. Area Density Mean of Species Showing Significant Variation between Areas 113 28. Quadrant Density Mean of Species Showing Signif­ icant Variation between Areas 115 29. Area Density Mean of Species Showing Significant Variation between Quadrats 117 30. Quadrant Density Mean of Species Showing Signif­ icant Variation between Quadrats 121 31» Area Density Mean of Species Showing Significant Variation between Areas and Also between Quadrats 126 X LIST OF TABLES—Continued

Table Page 32. Quadrant Density Mean of Species Showing Signif­ icant Variation between Areas and Also between Quadrats 12$ 33. Area Density Mean of Species Showing No Signif­ icant Variation between Areas, Quadrats, and Quadrants 130 34. Quadrant Density Mean of Species Showing No Significant Variation between Areas, Quadrats, and Quadrants 133 35. Analysis of Species Density and Their Source of Significance 136 36. Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association 138 37. Baboquivari, Molino, and El Capitan Canyon Area Species of Special Interest ...... 150 38. Species of Six Taxa Found in Study Areas 159 39. Percentages of Species with Highest Density Mean in Study Areas 161 LIST OF ILLUSTRATIONS

Figure Page 1. Type locations of Vauquelinia species 2 2. Vauquelinia californica collected by Major Emory • . 4 3. Vauquelinia californica seed from San Carlos area . 12 4. Vauquelinia study areas in Arizona 15 5. Ajo Mountain study area near Arch Canyon, showing Vauquelinia plants growing in rhyolite stream bed 19 6. Baboquivari Mountain study area showing Vauquelinia plants on granite cliffs and outcroppings ... 24 7. Molino Canyon study area showing Vauquelinia plants growing on granite gneiss outcroppings .... 29 &. El Capitan study area showing Vauquelinia plant on limestone outcroppings 34 9. San Carlos study area showing Vauquelinia plants growing in rocky stream bed . . . 39 10. Mormon Flat study area showing Vauquelinia and Fouquieria plants on tuff 43 11. Vauquelinia californica plant showing its petro- philous nature . • 4$ 12. Deliquescent nature of Vauquelinia californica • plant under harsh environmental conditions . . 49 13. Vauquelinia californica plant growing in tuff ... 50 14. Vauquelinia californica and its struggle for ex­ istence 52 15. Small Vauquelinia californica plant growing in limestone crevice in El Capitan area 53

xi xii LIST OF ILLUSTRATIONS—Continued

Figure Page 16. Effect of sufficient moisture and absence of damage from fire on a Vauquelinia plant in the Molino Canyon area 54 17. A Molino Canyon area Vauquelinia plant with numerous stems, the effect of adverse environ­ mental conditions 56 IS.• Vauquelinia californica showing fire scars and re- sprouting 57 19. Inflorescences of Vauquelinia californica growing in Molino Canyon area ..... 64 20. Inflorescences of Vauquelinia californica growing in Organ Pipe area 66 21. Variation of greenhouse-grown Vauquelinia plants from Molino Canyon area Si 22. Variation of greenhouse-grown Vauquelinia plants from San Carlos area 8j> 23• Variation of greenhouse-grown Vauquelinia leaves from Molino Canyon area £4 24« Variation of greenhouse-grown Vauquelinia leaves from El Capitan, San Carlos, Baboquivari, and Organ Pipe areas 86 25• Greenhouse-grown Vauquelinia #31^5 from Organ Pipe area 37 26. Greenhouse-grown Vauquelinia #3334 from Molino Canyon area 88 27• Greenhouse-grown Vauquelinia #3268 from San Carlos area 89 28. Relationship of density mean for two species with high association ..... 146 29* Upper study in Baboquivari Canyon area 157 30. Enlargement of Vauquelinia californica leaf col­ lected by Major Emory (lower right portion, Fig. 2) 166 ABSTRACT

Vauquelinia californica plants from mountains of central and. southern Arizona were studied for ecological and morphological variations. The study quadrats were located in six areas isolated from one another and located in the Ajo, Baboquivari, Santa Catalina, Mescal, and Superstition Mountains. Field observations were made of different eco­ logical aspects and leaves were collected from each quadrant for morphological investigation. In addition, seeds were collected for morphological study and for greenhouse experi­ ment. Plants grown from seed under similar environmental conditions we re studied for morphological variation. Herba­ rium specimens were borrowed from several major herbaria and studied. Density of plants on the study quadrants was re­ corded so that DiceTs Index might be applied. Analysis of variance using a hierarchical classifi­ cation ivas run on all leaf and seed data and on all species recorded in the study quadrants. Correlation analysis was also performed on the leaf and seed data. The Dice Association Index was applied to all the plant species recorded in all areas, a total of 144 species, and the application showed that 95 combinations of two species had an index of .50 or greater and that they occurred together four or more times. xiii Field, greenhouse, laboratory, herbarium, and sta­ tistical analysis showed that the Vauquelinia in the Ajo Mountains might be a new species. INTRODUCTION

The genus Vauquelinia. family Rosaceae, subfamily Spiraeoideae, was first described by Humboldt and Bonpland (l80&). The first species of this genus was discovered in Actopan, Mexico, and named Vauquelinia corymbosa Corr. Since its discovery ten species have been described. The genus is limited to the North American continent and only three species occur outside Mexico. Different species of Vauquelinia occur in several mountain ranges. Figure 1 shows the type localities for the ten present-day species. Vauquelinia plants are limited to mountainous terrain and occur either on cliffs, at the base of cliffs, or on rocky outcroppings. It grows in almost inaccessible areas some distance from the desert floor. Vauquelinia was a component of the Madro-Tertiary Geoflora (Axelrod, 195$). Brown (1934) found Vauquelinia in sediments in the Rocky Mountain Green River Eocene in Colorado, and also in Utah. The Oligocene Florissant (Colorado) flora contained two species of Vauquelinia (MacGinitie, 1953)• They were: fossil Vauquelinia coloradensis (Knowlton) MacGinitie, which is similar to the present Vauquelinia californica (Torr.) Sarg., and fossil Vauquelinia liniara MacGinitie 2

Tucspn

Chihuahua

•4, Monte

Guadalajara

Mexico City •10. \ 200 Miles

Fig. 1. Type locations of Vauguelinia species. 1. V. californica (Torr.) Sarg.; 2. V. pauciflora Standley; 3. V. angustifolia Rydb.; 4. V. heterodon Johnston; 5. V. Retherfordii Johnston; "E. V. latifolia Rydb.; 7. V. Karwinski Maxim.; S. V. potosina Painter; 9. V. corymbosa Corr.T 10. V. australis Standley. which resembles Vauquelinia angustifolia Rhydberg, now found in the Big Bend area of Texas and Mexico. Vauquelinia californica, collected by Major Emory while on a United States and Mexico boundary survey, was first named Spiraea californica by Torrey [iSl+B). Watson (IS76) found that Torrey had identified the plant incorrectly, and, subsequently, placed it in the genus Vauquelinia. Watson (1876) applied the specific epithet Torrevi to it. Sargent

(1$$9)} following taxonomic priority rules dropped the specific epithet Torrevi, and reapplied the specific epithet cali­ fornica. Thus, the species was finally named Vauquelinia californica. Figure 2 shows the specimen that Major Emory (1$59) collected in "high mountains near the Gila." The amount of material collected was limited and, as a result, Dr. Torrey placed it under the incorrect genus, Spiraea. The taxonomic description of Vauquelinia californica as given by Shreve and Wiggins (1964) is as follows: Shrub or small tree 6 m. tall with dark grey, nearly smooth bark; leaves lanceolate, O.S-2 cm. wide, to 10 cm. long, bright green and glabrate above, finely cinereous—tomentulose beneath, margins shallowly serrate, petioles 0.6-2 cm. long; flowers in terminal cymose panicles; hypanthium about 2 mm. deep, slightly wider, cinereous—tomentose; calyx lobes broadly ovate, 1-1.5 mm. long; petals white, oblong to obovate 3-4 mm. long, spreading to reflexed; capsule subwoody, of 5 follicle-like erect locules about 4 mm. high, rusty— puberulent /pp. 531-532,7• The extent of the geographical area in which the genus is found extends from Oaxaca, Mexico, in the south, north to the Gila River in south central Arizona; east from the Chisos Fig. 2. Vauquelinia califomica collected by Major Emory. Mountains in Big Bend National Park, Texas, west to Mountain El Tajo, near the United States border in Baja, California, then south to Cerro Natividad near San Ignacio, Baja, California. Two described species of Vauquelinia are found within the borders of Arizona: (1) Vauquelinia pauciflora, and (2) Vauquelinia californica.. Vauquelinia pauciflora occurs only in the extreme southeast corner of Arizona in the Guadalupe Canyon area and across the border in Mexico. More­ over, the author observed that Vauquelinia californica occurs immediately above the desert floor in the Upper Sonoran zone, and extends into the Pinyon-Juniper zone of southern Arizona. It may occur with Quercus, in which case, Vauquelinia grows on the rocky outcroppings. The author undertook a biosj^stematic study of the genus in 1966. A preliminary trip was made into Mexico and Texas to observe the genus growing in the field. Collections were made of materials which included young buds, flowers, seeds and seed capsules, where obtainable.- Leaves were also collected and numerous photographs were taken for laboratory study. While making the study of the genus, he became interested also in its ecological relationships. Very little has been published on Vauquelinia. What material is available deals with the plant's taxonomy. Therefore, a study was made to determine the phytosociological relationships of Vauguelinia and perhaps find some explanation for its morphological variability. The species Vauguelinia californica was chosen be­ cause of its ecological and morphological variability and further because it occurred in several .isolated mountain ranges. All plant names listed in Appendices A and B were taken from Arizona Flora (Kearney and Peebles, i960) with the excep­ tion of the Cactaceae the source for which was The Cacti of Arizona (Benson, 1969)• METHODS AND MATERIALS

Field Studies Vauquelinia may occur from the desert floor up into the lower Pinyon-Juniper zone in southern Arizona. There­ fore, quadrat selections were made from Vauquelinia plants encountered at lower elevations and from those found up and into higher elevations. In order to obtain as much homo­ geneity in sampling as possible, Vauquelinia plants selected were between two and four meters in height. Vauquelinia plants showing ecological variability were chosen in the six study areas. Preliminary sampling was carried out in one study area to determine plot size. A circular sample plot, three meters in radius or 2$.27 was adequate for the results desired; that is, an increase not greater than 10 per cent in plant species with a 10 per cent increase in sample area (Cain, 193^). The pivotal point of each circular plot was an individual Vauquelinia plant. The circular plot was divided, bjr compass, into four equal quadrants. The circular plot was divided by north-south and east-west dissections, making northeast, southeast, southwest, and northwest quadrants. Ten Vauquelinia plants were selected in each of the six study areas for a total of sixty study plots. No plants

7 were selected which would overlap or cause possible inter­ action to exist between the Vauquelinia plants. The physical features of each Vauquelinia plant were recorded for the following: 1. Height 2. Basal diameter 3. Number of main stems 4. Size of main stems 5. Estimate of age 6. Location of leaves 7. Vigor of plant 3. Growth pattern and floral and fruiting structure data were obtained as follows: 1. When the plant last flowered 2. Estimated per cent of inflorescences on the plant 3. Size of inflorescences as determined by the re­ maining capsules

Per cent of inflorescences was an estimate of the average number found upon the individual Vauquelinia plant. The basis upon which 100 per cent xras determined was by the author's observations and experience during past years of study. Width of inflorescences was an average for each plant and was taken from outermost capsule to outermost capsule. 9 Leaves were taken from each quadrant of every Vauguelinia plant in five quadrats of each of the six study areas. (The circular sample plot containing the Vauguelinia plant will hereafter be referred to as a quadrat.) Ten leaves, restricted to the largest leaves from the terminal clusters, were taken from each quadrant at from approximately breast to reachable height. All leaves in each quadrant of every quadrat were measured for length including the petiole and the petiole alone. Measurements were also made for leaf blade width, widest measurement; and number of leaf spines, per cm of linear length of leaf at widest measurement. Individual plant species for each quadrant vrere counted and recorded. All major species found around each of the six study areas were recorded. Field data from each quadrat included: (l) exposure, (2) per cent slope, (3) soil parent material, (4) soil depth, and (5) soil type. Information was noted as to the usefulness of Vauguelinia; i.e., whether it was browsed by livestock or foraged upon by insects or parasitized by other plants.

Greenhouse Studies In the fall of 1965> seeds were collected from each area under investigation for morphological variation studies. Greenhouse studies were performed to determine the germination and growth of seedlings under similar 10 environmental conditions. In September, 1966, three types of soil (1) Molino Canyon granite gneiss, (2) Rillito River sandy bottom land, and (3) limestone soil from Guadalupe Canyon area of Cochise County, Arizona, were blended into a mixture of one-third peat moss and one-third sand, placed in 4" x 4" black plastic pots, planted l/4n deep with Vauquelinia seeds, and watered. Germination of the seeds was approximately 3 per cent and studies were conducted to determine why the viability was so low. The study disclosed that greenhouse soil temperatures in September in Tucson, Arizona', were too high for germination of Vauquelinia cali- fornica. The greenhouse experiment was repeated on growth tables in the Agriculture Science Building. Good germination was obtained. The seedlings were transferred to the green­ house when they were approximately 3/4" in height. After ten months of growth, photographs were taken of relative variability between areas and within areas for purposes of comparison. Leaves of plants, samples from the different study areas, grown in the greenhouse were also photographed to show morphological variations. Ten seeds of Vauquelinia were randomly selected from five plants in the Molino, El Capitan, San Carlos, and Ajo areas; from four plants in the Baboquivari area; and from two plants in the Mormon Flat area. The following measurements were made: 11 1. Total length of seed, including wing 2. Length of seed 3. Width of seed (widest measurement) 4. Width of wing (widest measurement)

Figure 3 illustrates a Vauquelinia californica seed v/ith wing identified. The wing does not disarticulate at maturity and may remain attached to the seed for several years.

Laboratory Analyses Herbaria specimens of Vauquelinia, used to study morphological variations of the species, were obtained on loan from the following institutions: 1. Chicago Natural History Museum 2. Dudley Herbarium 3. Gray Herbarium 4. Herbario Nacional del Institute de Biologia, Universidad Nacional de Mexico 5. Missouri Botanical Gardens 6. New York Botanical Gardens 7. San Diego Museum of National History 3. United States National Herbarium 9. University of Arizona

Data recorded from leaf measurements, seed measure­ ments, and for density were analyzed by the use of a CDC 64OO computer. Leaf and seed measurements were 12

seed wing

seed body

Fig. 3. Vauquelinia californica seed from San Carlos area. statistically analyzed by prewritten programs of ANOVA 45, linear regression and correlation. The ecological association of Vauquelinia with other species was analyzed by computer using the Dice Association Index (Dice, 1945). The coefficient of associ­ ation was determined for all species. The Dice Index provides a direct measure of associ­ ation between any two species. The index is obtained by dividing the number (a) of random samples of a species in which species A occurs into the number of (h) samples in which species A and B occur together. Therefore: Association index B/A = h/a. The formula for the reciprocal index is: Association index A/B = h/b. An association index of 1 (one) would mean that species A and B occurred together in each sample. The association index may differ depending upon which species is used as the base. In order to indicate which species is used as a base for com­ parison, the base species is placed second in the statement: Association Association 1 2

Artemesia yf./Bouteloua jc. = 0.687 0.350 DESCRIPTION OF STUDY ARMS

All the study areas are located in Arizona and are within an area of approximately 57j600 square kilometers. They include five different mountain ranges which form the perimeter (Fig. 4)• The mountain ranges are separated by several kilometers of desert floor, making each area an island unto itself. Thus, to a great extent, plant and animal life are confined to a particular area. These mountain ranges have been physically separated since late

Miocene times. According to Benson and Darrow (1944)? Vauquelinia californica is presently known to grow in the Ajo, Baboquivari, Comobabi, Tat Momoli, Saw Tooth, State, Silver Bell, Picacho, Santa Rita, Whetstone, Rincon, Santa Catalina, Mescal, Superstition, Tortilla, and Pinal Mountains. Each of these mountains lies within or in close proximity to the perimeter which bounds the study area. Six study areas, isolated and representative of distinct populations of Vauquelinia californica., were chosen for ecological and morphological variability. Therefore, these areas represent a diversity of associated species. The study areas are: (1) Organ Pipe, Ajo Mountains; (2) Baboquivari Canyon, Baboquivari Mountains; (3) Molino Canyon, Santa Catalina Mountains; (4) El Capitan, Mescal Mountains; (5) San Carlos, Mescal Mountains; (6) Mormon

14 70 Miles

Fig. 4. Vauquelinia study areas in Arizona Flat, Superstition Mountains. Elevation of the six areas ranged from 792 to 1,5$4 meters. The most inaccessible were Grass and Arch Canyons in the Ajo Mountains (Organ Pipe area), and Baboquivari Canyon in the Baboquivari Mountains. In the six study areas Vauquelinia is found on sedimentary, igneous and metamorphic material. The Organ Pipe area consists of rhyolite and andesite; the Baboquivari Canyon area is granite; Molino Canyon, granite and granite gneiss; El Capitan, limestone and dolomite; San Carlos, sandstone and dolomite; and the Mormon Flat area, tuff. Mean temperature and precipitation for each of the areas are given in Table 1 (Smith, 1956). These figures were recorded at stations closest to the study area to make relative comparisons between study areas. Less Precipita­ tion and warmer temperatures were probably recorded than would have been in the study areas because the recording stations were at the base of or in close proximity to the mountains. In the winter season, according to Greene and Sellers (1964), temperatures at Mormon Flat, because of its proximity to Canyon Lake, may be higher than in the surrounding area.

Organ Pipe Area The Ajo Mountains, in which the Organ Pipe study area is located, are oriented in a north of northwest direction in Pima County, southwestern Arizona. They are approximately 40 TABLE 1 Mean Temperatures and Precipitation for Study Areas as Recorded at Stations-'-

Recording Station and Years Area Elevation Recorded Mean Jan, Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Annual

Organ Pipe 1944-1953 Temp. 51.10 54.40 58.20 66.50 72.60 79.90 87.60 86.90 83.10 71.70 59.20 52.80 68.60 Organ Pipe Cactus 1944-1953) Prec 00.61 00.46 00.66 00.31 00.01 00.01 00.76 01.33 01.28 00.43 00.76 00.78 07.40 1,663 El. 1937-1949) e

1917-1925) Tenp. 50.40 53-40 57.80 64.90 72.30 81.90 86.20 84.10 81.30 70.SO 57.90 52.40 67-80 Baboquivari Sells 1940-1953) Canyon 2,369 El. 1911-1913) Prec. 00.72 00.64 00.81 00.43 00.18 00.31 02.90 02.40 OO 00.62 00.78 00.71 11-44 1917-1925) .93

Sabir.o 1941-1953 Tenp. 51.10 54-00 58.10 66.80 74-30 82.70 87.90 85.10 Si.50 71.00 56.70 52.70 68.50 Molino Canyon Canyon St.Catalina 1941-1953 Prec. 00.80 00.79 00.SO 00.56 00.09 00.30 01.75 02.39 01.10 00.83 00.62 00.75 10.78 Mts. 2,610 El. El Globe 1905-1953 Teap. 43-60 47-80 53-10 60.10 67.40 76.80 82.20 80.30 75-20 63.80 51.40 44.20 62.30 Capitan 3,540 El. 1905-1953 Prec. 01.57 01.48 01.29 00.73 00.32 00.39 02.69 02.54 OI.32 00.92 01.14 01.71 16.10 San Carlos 1930-1953 Temp. 45-60 49-60 55-20 63.60 72.50 81.60 86.60 34-90 79.80 68.10 52.50 47-20 65-60 San Carlos Reservoir 2,532 El. 1631-1953 Prec. 01.33 01.42 01.15 00.52 00.25 00.26 01.70 02.08 01.04 00.77 00.96 01.50 12.98

Mormon Flat 1923-1953 Teap. 51.40 55-60 59.6O 67.60 78.10 66.60 92.20 89.60 86.00 74.60 62.30 54-30 71.60 Mormon Flat 1,715 El. 1923-1953 Prec. 01.25 01.61 01.37 00.79 00.23 00.30 01-08 02.04 01.28 00.55 01.07 01.68 13.25

^"Source for temperatures and precipitation: H. V. Saith, "The. Climate of Arizona," Agriculture Experiment Station Bulletin. 279, September, 1956, pp. 36-43 and pp. 68- 70, respectively. IS kilometers in length and from 7 to 10 kilometers wide (Interior-Geological Survey, 1957)• The western half of

* the mountains is part of Organ Pipe National Monument, and the eastern half is part of the Papago Indian Reservation. The highest elevation, 1,476 meters, is Mt. Ajo. Alluvial fans surround the base, beginning in the desert floor at approximately 609 meters elevation. The mountain proper starts at an elevation 91 to 121 meters higher. Two sites in the Ajo Mountains were selected for study: Arch Canyon and Grass Canyon. The two canyons drain west into the Sonoita valley. The terrain of both areas is extremely rugged and has numerous rocky cliffs. Neither site is readily accessible. The two areas are separated by approx­ imately 7 kilometers but approximately 4$ kilometers by vehicle. Vauquelinia plants first appear in each canyon at an elevation of approximately 762 meters and are found almost to the summit of the mountains. Vauquelinia grows mainly on the bottom and sides of rocky stream beds which contain water during the summer and winter rainy seasons after thunder­ storms. A typical area studied in the Ajo Mountains is shown in Figure 5« The Vauquelinia plants in the lower central portion of the photograph occur in a rocky stream bed. Fig. 5« Ajo Mountain study area near Arch Canyon, showing Vauquelinia plants growing in rhyolite stream bed. 1 vOi— 20 The dominant shrub of the general area is Simmondsia chinensis. At higher elevations there are fewer Simmondsia chinensis and Juniperus monosperma appears instead. Following is a list of plants that occurred on the study quadrats: Abutilon parvulum (see: Kearney, Peebles, and Collaborators, I960) Agave deserti Agave Schottii Aloysia Wrightii

\ Aristida ternipes Artemisia ludoviciana Bommeria hispida Bouteloua curtipendula Cheilanthes Lindheimeri Cheilanthes tomentosa Commelina erecta Dodonaea viscosa Ephedra fasciculata Eriogonum fasciculatum Eriogonum Wrightii Eupatorium pauperculum Euphorbia melanadenia Galium stellatum 21 Gutierrezia lucida Jacobinia ovata Janusia gracilis Maivastrum bicuspidatum Menodora scabra Mimosa biuncifera Muhlenbergia monticola Muhlenbergia Porteri Notholaena sinuata ' Notholaena sinuata var. integerrima Opuntia phaeacantha var. ma.ior (see: Benson, 1969) Pellaea Jonesii Pellaea limitanea Pellaea longimucronata Penstemon pseudospectabilis Rhynchosia texana Rivina humilis Selaginella arizonica Setaria macrostachva Simmondsia chinensis Stipa speciosa Tragia nepetaefolia Tridens muticus Viguiera deltoidea 22 Listed below are major plants that occurred outside the study- quadrats: Berberis haematocarpa Celtis reticulata Condalia lycioides Fouquieria splendens Haplopappus laricifolius Juniperus monosperma Lotus rigidus Lycium Berlandieri Nolina microcarpa Prosopsis .juliflora Salvia pinguifolia Sphaeralcea laxa

Baboquivari Canyon Area The Baboquivari study area, in the Baboquivari Mountains, is approximately kilometers east of the Ajo study area in Pima County and lies on the extreme east side of the Papago Indian Reservation. The Baboquivari Mountains are oriented in a north-south direction for approx­ imately 64 kilometers and are 10 to 13 kilometers wide. The base of the mountains, 1,066 meters elevation, has an accu­ mulation of approximately 91 meters of alluvium which slopes to the desert floor. Baboquivari Peak, 2,356 meters, is the highest elevation. 23 Two sites in the Baboquivari Mountains were se­ lected for study. Both sites are on the west side of the mountains slightly east and south of Baboquivari Canyon and occur on granite formations. The lower study area lies immediately below west-facing cliffs at 1,15$ meters eleva­ tion, and the upper area on southerly-facing cliffs at 1,524 meters elevation. The.study areas were reached by a trail which began at the Papago Indian Baboquivari camp and ascended to Baboquivari Peak. Vauquelinia in this area occurs primarily in crevices on cliffs or immediately below the cliffs (Fig. 6). However, some specimens occur on rocky outcroppings, away from the vicinity of the cliffs. Figure 6 shows several large Vauquelinia plants growing on the lower face of the cliff, several smaller plants farther up the cliff, and larger plants at the cliffrs base. Following is a list of plants that occurred on the study quadrats: Agave Schottii Anisacanthus Thurberi Aristida hamulosa Aristida ternipes Artemisia ludoviciana Ayenia pusilla Bouteloua curtipendula Fig. 6. Baboquivari Mountain study area showing Vauouelinia plants on granite cliffs and outcroppings. Bouteloua filiformis Bouteloua hirsuta Bouvardia glaberrima Calliandra humilis Carex sp. Cheilanthes Lindheimeri Commelina erecta var. crispa Crossosoma Bigelovii Dasylirion Wheeleri Dodonaea viscosa Elyonurus barbiculmis Eragrostis intermedia Eriogonum Wrightii Erythrina flabelliformis Euphorbia arizonica Euphorbia melanadenia Eysenhardtia polystachva Fououieria splendens Galium microphvllum Gossvoium Thurberi Gutierrezia lucida Halimolobos diffusus Iiaplopappus laricifolius Heteropogon contortus Krameria Grayi Krameria parvifolia Lagascea decipiens Leptochloa dubia Lycurus phleoides Mammillaria microcarpa Muhlenbergia Bmersleyi Muhlenbergia monticola Muhlenbergia Porteri Nissolia Schottii Nolina microcarpa Notholaena aurea Notholaena sinuata Qpxmtia phaeacantha var. discata Opuntia violacea var. santa-rita Oxalis stricta Panicum capillare Pellaea limitanea Pellaea longimucronata Porophyllum gracile Quereus oblongifolia Quercus reticulata Rhus trilobata Rhynchosia texana Simmondsia chinensis Yucca arizonica 27 Listed below are major plants that occurred outside the study- quadrats: Abutilon Thurberi Acacia angustissima Acacia Greggii Allionia incarnata Aloysia Wrightii Andropogon barbinodis Condalia lycioides Encelia farinosa Haplopappus laricifolius Hibiscus Coulteri Janusia gracilis Juniperus monosperma Lycium Berlandiera Mimosa biuncifera Notholaena integerrima Prosopsis .juliflora Quereus Emoryi Robinia neomexicana Trichachne californica

Molino Canyon Area The Molino Canyon study area is in the Santa Catalina Mountains which are approximately 112 kilometers northeast of the Baboquivari study area, and separated from 28 it by the desert floor. The Santa Catalina Mountains are approximately 16 kilometers northeast of Tucson, in Pima County. These mountains roughly form an isosceles triangle, the base of which is approximately 42 kilometers in length east-west; and the two sides lying east-northwest and west- northeast, respectively, are approximately 32 kilometers in length. The Santa Catalinas rise above alluvial fans from $53 meters elevation on the south and peak at 2,799 meters at Mount Lemmon. Two sites on the southwest side of the mountain were selected for study: Molino Canyon, elevation of 1,219 "to 1,341 meters; and an area north of the Federal Honor Camp, approximately 1,462 meters in elevation. At the lowest level, quadrats were selected at approximately 1,219 meters elevation; and at the highest, at approximately 1,5$5 meters. Vauquelinia occurs in the granite or granite gneiss rock crevices throughout the general area as shown in

Figure 7, or on cliffs. The Molino Canyon site has the most healthy and robust population of Vauquelinia plants the writer has seen on the North American continent. The Molino and Baboquivari Canyon areas were probably the only two studied ^7hich may receive snow regularly; how­ ever, it remains for only a few days. Molino Canyon also has a stream which flows for a few weeks each year, after the summer and winter rainy seasons. The areas also show Fig. 7* Molino Canyon study area showing: Vauauelinia nlairt-.s growing on granite gneiss outcroppings. 30 indications of having had more fires in the past than did any of the other study areas. Following is a list of plants that occurred on the study quadrats: Acacia Greggii Agave Palmeri Agave Schottii . Andropogon barbinodis Arctostaphylos pungens Aristida barbata Aristida ternipes Artemisia ludoviciana Ascelpias angustifolia Ayenia pusilla Bommeria hispida Bouteloua curtipendula Bouteloua filiformis Bouteloua hirsuta Calliandra humilis Cereus giganteus Cheilanthes Lindheimeri Cheilanthes tomentosa Crossosoma Bigelovii Dalea formosa Dasylirion Wheeleri Eragrostis intermedia Eriogonum Wrightii Erythrina flabelliformis Euphorbia melanadenia Ferocactus Wislizenii Fouquieria splendens Galactia Wrightii Gossypium Thurberi Haplopappus laricifolius Heteropogon contortus Janusia gracilis Jatropha cardiophylla Krameria parvifolia Leptochloa dubia Lotus rigidus Lycurus phleoides Mammillaria microcarpa Melampodium leucanthum Muhlenbergia Emersleyi Notholaena sinuata Opuntia phaeacantha var. laevis Opuntia versicolor Pellaea Jonesii Pellaea limitanea Pellaea longimucronata Selaginella ruuincola Trichachne californica Trixis californica

Listed below are major plants that occurred outside the study- quadrats:

Acacia angustis'sima Baccharis sarothroides Condalia lycioides Fendlera rupicola Juniperus deppeana Mimosa biuncifera Nolina microcarpa Phoradendron flavescens Pinus cembroides Prosopsus .juliflora Quercus Emoryi Quercus oblongifolia Rhamnus crocea Rhus trilobata Selaginella arizonica Sphaeralcea Fendleri

El Capitan Canyon Area The El Capitan study area is approximately 104 kilometers north of the Molino Canyon study area, in Gila 33 County. It is 26 kilometers north of Winkelman, east of Arizona State Highway 77 in the Mescal Mountains. The Mescal Mountains, oriented in a northwest-southeast direc­ tion, are approximately 4$ kilometers in length and 19 to 24 kilometers wide. They do not rise abruptly from the desert floor as do the Ajo, Baboquivari, and Santa Catalina Mountains, but increase in elevation from 5$7 meters at Winkelman to 2,392 meters at Pinal Peak which is 32 kilo­ meters to the northwest. The specific area of study is .9 kilometers west of El Capitan Canyon at an elevation of 1,097 meters. The parent material of the area is limestone and dolomite, both very much pitted and cracked. The Vauquelinia plants (Fig. g) are located almost exclusively in this strata. In fact, it is very easy to identify limestone outcropping by the presence of Vauquelinia plants. Limestone out- croppings in this area are somewhat similar to those found in the Guadalupe Canyon area of Cochise County, Arizona, and also those near Oaxaca, Oaxaca, Mexico, both of which have good growth of Vauquelinia. The study area is not as rugged as the Ajo, Baboquivari, Santa Catalina, and San Carlos areas. It has been and is currently grazed by domestic livestock. Fig. g. El Capitan study area showing Vauauelinia nlant. nn limestone outcroppings.

•f- 35 Following is a list of plants that occurred on the study quadrats: Abutilon parvulum Acacia constricta Acacia Greggii Agave Palmeri Agave Toumeyana Aloysia Wrightii Arabis perennans Aristida adscensionis Aristida Fendleriana Aristida pansa Aristida ternipes Artemisia ludoviciana Baccharis glutinosa Berberis trifoliolata Bouteloua curtipendula Bouteloua filiformis Bouteloua hirsuta Calliandra humilis Cassia Covesii Ceanothus Greggii Cercocarpus montanus Cheilanthes Lindheimeri Condalia lycioides 36 Dalea formosa Dasylirion Wheeleri Dodonaea viscosa Draba cuneifolia Echinocereus fascicu.1atus var. • Boyce-Thompsonii Eriogonium Wrightii Evolvulus pilosus Fouquieria splendens Galium stellatum Gutierrezia lucida Heteropogon contortus Hilaria Belangeri Krameria Grayi Mammillaria microcarpa Melampodium leucanthum Metastelma arizonicum Mimosa biuncifera Muhlenbergia Emersleyi Muhlenbergia Porteri Nolina microcarpa Notholaena sinuata Notholaena sinuata var. integerrima Opuntia a cant ho carpa var. ma.jor Opuntia phaeacantha var. discata Panicum arizonicum Panicum Hallii 37 Pellaea Jonesii Pellaea limitanea Penstemon pseudospectabilis Porophyllum gracile Psilostrophe Cooperi Quercus turbinella Salvia pinguifolia Selaginella arizonica Simmondsia chinensis Sphaeralcea Fendleri Sphaeralcea laxa Stipa comata Stipa neomexicana Stipa speciosa Tribulus terrestris Tridens muticus Yucca baccata Zinnia pumila

Listed belov; are major plants that occurred outside the study- quadrats: Allionia incarnata Baccharis sarothroides Celtis reticulata Cercidium floridium Encelia farinosa Ephedra fasciculata Hibiscus Coulteri Hyptis Emoryi Janusia gracilis Notholaena integerrima Prosopis .juliflora Tridens pulchellus

San Carlos Area The San Carlos study area is approximately 32 kilo­ meters east of the El Capitan study area and lies on the northeast slope of the Mescal Mountains within the San Carlos Apache Indian Reservation in Pinal County. The specific area of study is 3.5 kilometers east of Coolidge Dam, approximately 300 meters east of the road to Calva, in the cliff areas. The Mescal Mountains have already been described. This study area has sandstone and dolomite out- croppings and the formations slope downward toward the southwest and tilt upward to the northwest (Fig. 9)• Drainage of the general area is northwest into the San Carlos reservoir. The elevation at the study area is $53 meters, and the terrain is steep and extremely rugged. Most of the Vauquelinia plants are found immediately below the large cliffs or in the rocky stream beds (Fig. 9) which drain the area. In all instances Vauquelinia is found growing in 39

Fig. 9. San Carlos study area showing Vauauelinia plants growing in rocky stream bed. cracks in rocks. Figure 9, lower center, shows two rather large Vauquelinia plants v/hich occur in the roclcy stream bed. The occurrence of the plants in this area is somewhat parallel to that in the Ajo study area. Following is a list of plants that occurred on the study quadrats: Acacia Greggii • Agave Palmeri Agave Tourneyana Aloysia Wrightii Andropogon barbinodis Arabis perennans Aristida Wrightii Artemisia ludoviciana Ayenia pusilia Bouteloua curtipendula Brickellia atractyloides Canotia holacantha Celtis pallida Dalea formosa Dasvlirion Wheeleri Dodonaea viscosa Echinocereus fasciculatus var. Boyce-Thompsonii Ephedra fasciculata Ferocactus acanthodes var. LeContei • Galium stellatum Gutierrezia lucida Krameria parvifolia Leptochloa dubia Menodora scabra Muhlenbergia Porteri Opuntia acanthocarpa var. ma.jor Opuntia phaeacantha var. discata Pellaea Jonesii Pellaea limitanea Pellaea longimucronata Penstemon pseudospectabilis Selaginella arizonica Simmondsia chinensis Tridens muticus

Listed below are major plants that occurred outside the study- quadrats: Berberis trifoliolata Fendlera rupicola Haplopappus laricifolius Prosopsis .juliflora Psilostrophe Cooperi Selaginella arizonica

Mormon Flat Area The Mormon Flat study area is located approximately 88 kilometers northwest of the El Capitan area. It is in 42 Maricopa County, approximately 5 kilometers east of Mormon Flat Dam on the western edge of the Superstition Mountains which extend approximately 41 kilometers east and west and approximately 32 kilometers north and south. They rise from the edge of alluvium at 579 meters elevation and climax at Iron Mountain at 1,&45 meters. The southern edge of the mountains borders the desert floor; the northern edge, the Salt River.

The study area is at an elevation of approximately 747 meters and drains northwest into the Salt River. Vauquelinia plants grow in tuff which is composed of light cream-colored, fine-grained volcanic fragments filled with vesicles. The rock has deep cracks and, consequently, good water storage pos­ sibilities.

Figure 10 shows large, flat, exposed rocks from the crevices of which Vauquelinia grows. The figure also shows a Vauquelinia and Fouquieria plant growing from a crevice on a rock which protrudes above the surrounding terrain. The highest hills in the immediate vicinity are 'only a few hundred feet above the study area; thus, the Vauquelinia has had no place to migrate in periods of adverse environ­ mental conditions and, consequently, the population is almost extinct. The population found here was the smallest studied. Fig. 10. Mormon Flat study area showing Vauouelinia and Fouquieria plants on tuff. Following is a list of plants that occurred on the study quadrats: Abutilon parvulum Acacia Greggii Andropogon barbinodis Arabis perennans Aristida adscensionis Aristida Parishii Ayenia pusilla Bouteloua curtipendula Bouteloua filiformis Calliandra humilis Carex sp. Ceanothus Greggii Cercidium microphyllum Chrvsopsis hispida Crossosoma Bigelovii Dodonaea viscosa Echeveria collomae Echinocereus fasciculatus var. Bovce-Thompsonii Encelia farinosa Ephedra fasciculata Eriogonum fasciculatum Eriogonum Wrightii Euphorbia melanadenia Ferocactus acanthodes var. LeContei 45 Fouquieria splendens Galium stellatum Gutierrezia lucida Haplopappus spinulosus Hibiscus Coulteri Lotus rigidus Lycium Berlandieri Metastelma arizonicum Mimosa biuncifera Opuntia acanthocarpa var. ma.ior Opuntia phaeacantha var. discata Panicum arizonicum Panicum capillare Pellaea limitanea Porophvllum gracile Selaginella arizonica Simmondsia chinensis Sphaeralcea laxa Tridens muticus Viguiera deltoidea

Listed below are major plants that occurred outside the study quadrats: Cereus giganteus Cassia Covesii Cheilanthes Fendleri Cirsium neomexicanum Condalia mexicana Eriogonum inflatum Haplopappus laricifolius Pellaea longimucronata RESULTS

Field Studies Numerous photographs, all considered by the author to be typical of the particular issues under study, were taken during the field study period. These were made a part of this paper as an aid to the reader in following the re­ sults presented. Figure 11 depicts Vauquelinia californica and its petricolous habit. The plant shown was found in the Molino Canyon area, at approximately 1,2§1 meters elevation, growing in granitic rock. The base of the plant is approximately 60 cm in diameter with branches occurring immediately above the portion shown in the photograph. The granitic rock material has been split and lifted by the tremendous force of the roots as noted in the lower left of the photograph. Vauquelinia dies back during adverse environmental conditions and resprouts under more favorable ones (Fig. 12). The root of this plant, approximately 10 cm in diameter, grows from a rock crevice. Stems are shown here at the top of the photograph and the root occurs immediately below and to the left of the ruler. The ability of the Vauquelinia to survive in almost solid rock is depicted in Figure 13. This particular plant

47 Fig. 11. Vauquelinia californica plant showing its petrophilous nature. •p- 00- Fig. 12. Deliquescent nature of Vauauelinia californica plant under harsh environmental conditions. •p- vO Fig. 13. Vauauelinia californica plant growing in tuff 51 is growing in almost solid tuff. The absence of vegetation in the immediate vicinity, except for a few small shrubs on the right side of the figure, is evident. These shrubs are growing in small depressions in which soil has collected. Cercidium microphvllum is seen in the background, growing in material composed of both rock and soil. The ability of'Vauquelinia to germinate, survive, and propagate is remarkable (Fig. 14). The Vauquelinia plant is growing in a large granite boulder which has rolled down the mountain from the cliffs above. Germination occurred in the rock crack and the roots grew downward approx­ imately three meters before reaching soil. The pressure of the roots against the rock crevice forced and broke off a portion as is evidenced by exposed roots in foreground. Very few small Vauquelinia plants were observed by the author during this study. Moreover, the greatest number was seen on limestone (Fig. 15). During six years of observa­ tion, the author saw only one plant smaller than the one shown here. Under favorable environmental conditions, Vauquelinia becomes large (Fig. 16). The diameter of the Vauquelinia plant shown is approximately 57 cm. It is a large plant; however, the author has seen larger in the Organ Pipe area. The base of the plant shown in Figure 16 is growing from rock and, during the lifetime of the tree, sand and gravel have been deposited against it. Fig. 14. Yauquelinia californica and its struggle for existence n8"^1 Vauquelinia californica plant growing in limestone crevice m El Capitan area. Fig. 16• Effect of sufficient moisture and absence of damage from fire on a Vauouelinia plant in the Mblino Canyon area. 55 Figure 17 shows a Vauquelinia plant with numerous stems which indicate unfavorable environmental conditions in the past. The plant in Figure 16 shows one that has had favorable environmental conditions. The Vauquelinia plant in Figure 17 occurred in the Molino Canyon area which has had fires occasionally. The Baboquivari Canyon area also has been subjected to fires in the past as is evidenced by the plants and their remains. Charred stumps of Quereus. burned and scarred Vauquelinia plants (Fig. 1$), and more recent remains of Yucca arizonica, Dasylirion Wheeleri, and Agave Schottii are numerous. The abundance of grass in this area also indicates frequent and recent burns. The Vauquelinia plant in Figure 1$ shows evidence of past fires bjr the presence of dead branches on the left side of the photograph. The plant resprouted from its base and has subsequently attained almost its original height. The percentage of inflorescences upon each Vauquelinia plant and the inflorescence width were recorded for 196$ and 1969 (Tables 2-7). Figure 19, a portion of a Vauquelinia plant slightly past its peak flowering period, represents what the author (Tables 2-7) called 95 per cent in inflorescences. The Vauquelinia plant was growing in the Molino Canyon area. Few plants with larger inflorescences or more profuse flowering than that illustrated were observed. Fig. 17. A Molino Canyon area Vauauelinia plant with numerous stems, the effect of adverse environmental conditions. oVJl Fig. IS. Vauquelinia califomica showing fire scars and resprouting. TABLE 2 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant Organ Pipe Quadrats

Organ Pipe Area Year: 1969 1 Year: 1963 Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 0 0.0 10 2.5-5.0 2 0 0.0 25 2.5-5.0 3 7 2.5 50 2.5-5.0 4 0 0.0 0 0.0 5 0 0.0 7 2.5-5.0 6 0 0.0 0 0.0 7 0 0.0 75 5.0-8.0 6 5 2.5 20 2.5-5.0 9 0 0.0 75 2.5-5.0 10 0 0.0 20 2.5 TABLE 3 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant Eaboquivari Canyon Quadrats

Baboquivari Canyon Area Year: 1969 Year: 196 & Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 0 0.0 45 2.5 2 0 0.0 75 5.0 3 0 0.0 55 2.5-5.0 * 4 75 2.5-5.0 0 0.0 5 40 2.5-5.0 0 0.0 6 0 0.0 0 0.0 .7 0 0.0 15 2.5-5.0 3 5 2.5-5.0 0 0.0 9 2 2,5 40 2.5-5.0 10 60 2.5 5 2.5 TABLE 4 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant Molino Canyon Quadrats

Molino Canyon Area Year: 1969 Year: 1968 Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 0 0.0 30 5.0 2 0 0.0 90 2.5-10.0 3 -5 2.5 50 2.5- 5.0 4 1 2.5 5 2.5- 5.0 5 0 0.0 30 2.5- 5.0 6 0 0.0 0 0.0 .7 0 0.0 50 2.5 g S5 2.5-5.0 5 2.5- 5.0 9 0 0.0 25 2.5 10 20 2.5 2 2.5- 5.0 TABLE 5 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant El Capitan Quadrats

El Capitan Area Year: 1969 1 Year: 1963 Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 30 3.0-10.0 70 3.0-10.0 2 30 2.5- 3.0 0 0.0 3 50 2.5- 3.0 50 2.5-10.0 4 30 2.5- 5.0 0 0.0 5 90 2.5- 5.0 0 0.0 6 90 2.5- 3.0 0 0.0 7 50 2.5- 3.0 75 2.5- 3.0 a 35 2.5-10.0 2 2.5- 3.0 9 99 2.5-13.0 1 2.5- 3.0 10 25 2.5- 3.0 25 2.5- 3.0 TABLE 6 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant San Carlos Quadrats

San Carlos Area Year: 1969 Year: 1963 Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 50 5.0 35 5.0- 3.0 2 15 2.5-3.0 65 2.5- 3.0 1 • . O

40 2.5-3.0 \ji 3 30 vn 4 75 2.5-^.0 0 0.0 5 2 2.5 35 2.5-10.0 6 5 2.5 75 2.5- 5.0 7 4 2.5-3.0 30 2.5-10.0 3 5 2.5-5.0 75 2.5- 3.0 9 10 2.5-3.0 75 2.5- 3.0 10 10 2.5-5.0 75 2.5- 3.0 TABLE 7 Per cent of Inflorescences and Inflorescence Width on Each Vauquelinia californica Plant Mormon Flat Quadrats

Mormon Flat Area Year: 1969 Year: 1968 Width of Width of Quadrat Per cent of inflorescence Per cent of inflorescence No. inflorescences (cm) inflorescences (cm)

1 30 5.0 80 5.0- 8.0 2 5 2.5- 5.0 85 2.5-10.0 3 0 0.0 50 2.5- 8.0 4 1 2.5 50 2.5- 8.0 5 65 2.5- 8.0 40 •2.5- 8.0 6 75 2.5-10.0 5 2.5-10.0 7 8 2.5- 5.0 50 2.5- 8.0 8 0 0.0 50 2.5-10.0 9 0 0.0 0 0.0 10 2 2.5 75 2.5- 8.0 Fig. 19. Inflorescences of Vauquelinia califomica growing in Molino Canyon area. 65 Vauquelinia plants in the Organ Pipe area have much smaller inflorescences (Fig. 20) than any others in the areas under study. Almost every branchlet shown is terminated by an inflorescence, and the plant shown here was considered to be approximately 95 per cent in flower. The disparity in size and the number of flowers between the Molino Canyon area and Organ Pipe area inflorescences is illustrated by a comparison of Figures 19 and 20. The percentage of inflorescences varied from 1 to 95 per cent. The Organ Pipe and Molino Canyon areas (Tables 2 and 4, respectively) had a low percentage of inflorescences in 1969j while the San Carlos and El Capitan areas (Tables 5 and 6, respectively) had a high percentage of inflorescences during the same year. San Carlos and Mormon Flat areas (Tables 6-7) had a higher percentage of inflorescences than any of the other areas in 1963; the Baboquivari area (Tables 3-5) and the El Capitan area had the lowest. The Baboquivari area had approximately the same percentage of inflorescences for both years.

Tables 2-1 show that not all plants in a given study area flowered each year and that some plants did not flower in either 1963 or 1969* Some plants flowered in only one year, and still others flowered both years. The per cent slope and direction of each quadrat are given in Table 8. The Mormon Flat study area had least slope, 16.6 per cent; the San Carlos area, which averaged 32.3 Fig. 20. Inflorescences of Vauquelinia californica growing in Organ Pipe area. TABLE 8 Per cent Slope and Direction for Each Quadrat for Each Area

Baboquivari Or.tan Pine Canvon Kolir.o Canyon El Canitan San Carlos Mormon Flat Quadrat * Slope i0 Slope Slope % Slope 5S Slope JS Slope Ko. Slope Direction Slooe Direction Slone Direction Slope Direction Slope Direction Slope Direction 1 27.0 KHW 24-7 W 20.2 S 16.2 NW 27.0 N 17.5 N 2 27.0 KWW 41.4 SW 27.0 w 32.4 NE 18.0 NNW 16.6 NW 3 27.0 NW 36.9 S 26.5 w . 29.7 N 29.7 N 18.0 NW 4 20.2 E' 29.7 HUE 23-4 E 18.0 NW 74.2 N 15.7 H 5 13-5 W 32.4 W 16.6 SE 20.2 NW 36.9 N 17.1 m 6 20.7 N 22.0 NW 28.8 E 16.6 NW 36.9 NW 18.0 KNW 7 27.0 N 31.5 W 27.0 NE .18.0 W 10.3 N 18.9 NNW 8 27.9 NW 29.8 NNW 12.6 E 20.7 WNW 37.8 WNW 18.0 N 9 40.5 H 36.9 W 19.8 NNE 15-3 w 21.6 W 14.4 N 10 42.3 NN3 9.0 NW 35.1 S 22.5 s 30.6 W 12.1 N

• Avg. $ Slope 27-3 29.4 23-7 20.9 32.3 16.6 per cent slope, had the steepest. The over-all average for all study areas was 25.0 per cent slope. Slope values ranged from 9.0 per cent in the Baboquivari Canyon area to 74.2 per cent in the San Carlos area. The number of slope directions for study plots varied (Table 8). Thirty-tiro quadrats had a more western exposure, 14 more northern, 10 eastern, and 4 a more southern exposure. The more eastern and southern facing slopes were not common to the areas studied, thereby accounting for the low number of quadrats sampled. The frequency of Vauquelinia plants, according to the number of stems, is given in Table 9 for each area. The most frequent number of stems per plant was four. Plants with four, five or six stems were the most predominant frequency values with 56.66 per cent of the plants having from four to six stems. The Mormon Flat area had more plants with a larger number of stems than any other area. The Organ Pipe area was found to have the least number of stems per Vauquelinia plant.

Floristics Forty-four different families of plants composed of 144 different species (Appendices A and B) were found growing within the study plots. Pteridophytes and spermatophytes are both recorded. The pteridophytes listed have two families, the Polypodiaceae and Selaginellaceae; the Polypodiaceae is represented by nine species and the Selaginellaceae by two. TABLE 9 Frequency of Vauquelinia californica According to Number of Stems in Each Area

Frequency of Plants No. of Stems Organ Baboquivari Molino El San Mormon on Plant Pipe Canyon Canyon Capitan Carlos Flat Total

1 0 2 0 0 1 0 3 2 1 0 2 0 0 1 4 3 2 1 0 1 1 1 6 4 4 4 1 3 2 0 14 5 2 1 2 2 2 1 10 6 0 1 3 3 1 2 10 7 0 0 1 0 1 0 2

• $ 1 0 0 0 1 2 4 9 0 1 0 1 1 0 3 10 0 0 1 0 0 3 4 70 The spermatophytes have both gymnosperms and angiosperms; the Gymnospermae one family, the Ephedraceae. The Angiospermae included both Monocotyledoneae and Dicotyledoneae. The Monocotyledoneae had five families and 41 species, all of which were found within the quadrats. The largest single family, by number of species present, was the Gramineae with 30, 22 of which were in the subfamily Festucoideae, and S in the Panicoideae. The Dicotyledoneae had 91 species in 34 families. Families with the most numerous species were the: (l) Com- positae with 16: (2) Leguminosae, 15; (3) Cactaceae, 11; (4) Malvaceae, 6; and (5) Euphorbiaceae, 4. These five families in the Dicotyledoneae comprised 36.11 per cent of all species; the other 29 families of Dicolyledoneae com­ prised 20.^3 per cent of the total number of species. Abundance and density were recorded for all species (Table 10). Abundance, as used in this study, means the total number of occurrences of the plant on all study quad­ rants. (Density is the average number of times the plant occurred in a study quadrant.) Twelve species occurred in more than 100 sample plots; five species between 75 and 100 times; five between 50 and 75; twenty-two between 25 and 50 times; thirty-five species between 10 and 25; and sixty-five species occurred less than 10 times. There were no particular groupings of families within these distributions. Six species 73. TABLE 10 Abundance and Density of Species Recorded in All Study Areas

Abundance Density Species (total no.) (no. per quadrant)

Bouteloua curtipendula 494 2.05S Selaginella rupincola 416 1.733 Selaginella arizonica 302 1.25$ Agave Schottii 294 1.225 Cheilanthes Lindheimeri 237 .937 Gutierrezia lucida 175 .729 Tridens muticus 166 .692 Artemisia ludoviciana 157 .654 Calliandra humilis 157 .654 Arabis perennans 151 .629 Panicum arizonicum IIS .492 Aristida adscensionis 107 .446 Dalea formosa 94 .392 Bouteloua filiformis 93 .337 Haplopappus laricifolius 92 .333 Simmondsia chinensis 32 .342 Pellaea limitanea SO .333 Euphorbia melanadenia 67 .279 Eriogonum Wrightii 63 N .262 Eragrostis intermedia 56 .233 Porophyllum gracile 54 .225 72 TABLE 10—•Continued« Abundance and Density of Species Recorded in All Study Areas

Abundance Density Species (total no.) (no. per quadrant) Galium stellatum 51 »212 Notholaena sinuata 49 .204 Muhlenbergia Porteri 46 .192 Bouteloua hirsuta 43 *179 Mimosa biuncifera 42 .175 Viguiera deltoidea 40 .167 Jacobinia ovata 3& .15$ Acacia Greggii 37 .154 Aristida ternipes 37 .154 Heteropogon contortus 36 .150 Aloysia Wrightii 35 .146 Agave Palmeri 34 .142 Pellaea longimucronata 34 .142 Leptochloa dubia 33 »137 Fouquieria splendens 32 .133 Dodonaea viscosa 31 .129 Abutilon parvulum 30 .125 Haplopappus spinulosus 30 .125 Gossypium Thurberi 28 .117 Krameria parvifolia 27 .112 Rhynchosia texana 27 .112 Echinocereus fasciculatus var. Boyce-Thompsonii 26 .10$ Stipa speciosa 25 .104 73 TABLE 10--•Continued. Abundance and Density of Species Recorded in All Study Areas Abundance Density Species (total no.) (no. per quadrant) Opuntia acanthocarpa var. major 24 .100 Ayenia pusilla • 22 .092 Ephedra fasciculata 22 .092 Sphaeralcea laxa 21 .0#7 Lotus rigidus 20 .083 Mammillaria microcarpa 20 .033 Agave Toumeyana 19 .079 Andropogon barbinodis 19 .079 Brickellia atractyloides 19 .079 Salvia pinguifolia 19 .079 Anisacanthus Thurberi 1$ .075 Eysenhardtia polystachya 13 *075 Panicum capillare 1$ .075 Dasylirion Wheeleri 17 .071 Eupatorium pauperculum 17 .071 Opuntia phaeacantha var. discata 17 .071 Echeveria Collomae 16 .067 Cercidium microphyllura 15 .063 Pellaea Jonesii 15 .063 Aristida YJrightii 14 .05& Carex sp. 14 .053 Ceanothus Greggii 14 .05S TABLE 10—Continued. Abundance and Density of Species Recorded in All Study Areas Abundance Density Species (total no.) (no. per auadrant) Erythrina flabelliformis 14 .056

Panicum Hallii 14 .056 Sphaeralcea Fendleri 14 .056 Muhlenbergia monticola 13 .054 Eriogonum fasciculatuin 12 .050 Nissolia Schottii 12 .050 Aristida barbata 11 .046 Crossosoma Bigelovii 11 .046 Lagascea decipiens 11 .046 Menodora scabra 11 .046 Tragia nepetaefolia 11 .046 Bommeria hispida 10 .042 Muhlenbergia Eraersleyi 10 .042 Penstemon pseudospectabilis 9 .037 Aristida Fendleriana 6 .033 Baccharis glutinosa 6 .033 Krameria Grayi 6 .033 Lycurus phleoides 6 .033 Nolina microcarpa 6 .033 Canotia holacantha 7 .029 Melampodium leucanthum 7 .029 Notholaena aurea 7 .029 Berberis trifoliolata 6 .025 75 TABLE 10--Continued. Abundance and Density of Species Recorded in All Study Areas Abundance Density Species (total no.) (no. per quadrant) Coraraelina erecta 6 .025 Ferocactus acanthodes var. LeContei 6 .025 Notholaena sinuata 6 .025 Aristida hamulosa 5 .021 Chrysopsis hispida 5 .021 Commelina erecta 5 .021 Condalia lycioides 5 .021 Hibiscus Coulteri 5 .021 Metastelma arizonicum 5 .021 Opuntia versicolor 5 .021 Trichachne californica 5 .021 Yucca baccata 5 .021 Aristida Parishii 4 .017 Cheilanthes tomentosa 4 .017 Draba cuneifolia 4 .017 Halimolobos diffusus 4 .017 Quercus turbinella 4 .017 Rhus trilobata 4 .017 Agave deserti 3 .012 Galactia Wrightii 3 .012 Hilaria belangeri 3 .012 Janusia gracilis 3 .012 Jatropha cardiophylla 3 .012 76 TABLE 10—Continued. Abundance and Density of Species Recorded in All Study Areas Abundance Density Species (total no.) (no. per quadrant) Lycium Berlandieri 3 .012 Acacia constricta 2 .005 Bouvardia glaberrima 2 .005 Cassia Covesii 2 .005 Cercocarpus montanus 2 .005 Encelia farinosa 2 .005 Evolvulus pilosus 2 .005 Ferocactus Wislizenii 2 .005 Malvastrum bicuspidatum 2 .005 Opuntia phaeacantha var. laevis 2 .005 Opuntia violacea var. santa-rita 2 .005 Psilostrophe Cooperi 2 .005 Rivina humilis 2 .005 Arctostaphylos pungens 1 .004 Aristida pansa 1 .004 Asclepias angustifolia 1 .004 Celtis pallida 1 .004 Cereus giganteus 1 .004 Elyonurus barbiculrais 1 .004 Euphorbia arizonica 1 .004 Galium microphyllum 1 .004 Opuntia phaeacantha var. major 1 .004 77 TABLE 10—Continued* Abundance and Density of Species Recorded in All Study Areas Abundance Density Species (total no.) (no. per quadrant) Oxalis stricta 1 .004 Quercus oblongifolia 1 .004 Quercus reticulata 1 .004 Setaria macrostachya 1 .004 Stipa comata 1 .004 Stipa neomexicana 1 .004 Tribulus terrestris 1 .004 Trixis californica 1 .004 Yucca arizonica 1 .004 Zinnia pumila 1 .004 7^ had a density greater than .500 but less than 1.000, 35 species had a density greater than .100 but less than .500, and the remaining 99 less than .100. Bouteloua curtipendula had the highest density, 2.059 per quadrant (Table 10) ; Selaginella rupincola,-1- Selaginella arizonica, and Agave Schottii had a density of 1.000 or greater. Twenty-four species occurred in at least four or more study areas (Table 11). Two species, Bouteloua curti­ pendula and Pellaea limitanea, occurred in all six study areas. Five species occurred in 5 study areas, seventeen species in 4 study areas, twenty in 3, twenty-eight in 2, and seventy-two species occurred in only 1 study area.

Greenhouse Studies A greenhouse on the main campus of The University of Arizona was used to grow Vauquelinia plants under identical environmental conditions. Several plants from each area were grown. After ten months of growth, a number of photographs, illustrative of the variability within and between the areas of study, was taken. Greenhouse-grown Vauquelinia plants from the Molino Canyon area showed considerable variation in height (Fig. 21).

iThe Selaginellaceae and Polypodiaceae sampled in this study do not lend themselves to accurate count because of their growth habit. Therefore, the counts listed are approximations. 79 TABLE 11 Species Occurring on Four or More Areas

No. of Areas in which Species Occurred Species 6 Bouteloua curtipendula 6 Pellaea limitanea 5 Artemisia ludoviciana 5 Dodonaea viscosa 5 Eriogonura Wrightii 5 Gutierrezia lucida 5 Simmondsia chinensis 4 Acacia Greggii 4 Aristida ternipes 4 Ayenia pusilia 4 Bouteloua filiformis 4 Calliandria humilis 4 Cheilanthes Lindheimeri 4 Dasylirion Wheeleri 4 Euphorbia melanadenia 4 Fouquieria splendens 4 Galium stellatum 4 Muhleribergia Porteri 4 Notholaena sinuata 4 Opuntia phaeacantha var. discata 4' Pellaea Jonesii £0 TABLE 11—-Continued 4 Pellaea longimucronata 4 Selaginella arizonica 4 ' Tridens muticus li

Fig. 21. Variation of greenhouse-grovm Vauauelinia plants from Molino Canyon area. 32 Plant No. 15, for example, was 55 cm in height, and plant No. 39 was 16 cm, a difference of 39 cm. Plants from the San Carlos area (Fig. 22) ranged in height from 23 cm, plant No. 39, to 14.5 cm, plant No. 24, a difference of S.5 cm. This difference is quite a contrast compared to the difference of 39 cm among the Molino Canyon area plants. The San Carlos plants appear to be much more homogeneous than those of the other areas. Figure 23, Vauquelinia leaves from seven different greenhouse-grown Molino Canyon area plants, shows the varia­ tion that exists among Vauquelinia leaves. The two leaves on the far left of the figure are also indicative of Vauquelinia leaves in the Baboquivari Canyon area. The three leaves to the right are what one might expect to find in the San Carlos or the El Capitan areas. Ifcwever, the San Carlos leaves are usually wider than those shown here. From left to right, it is noted that leaves three and seven have very small stipules, and those of leaves two and five are large. Leaves one and two are undulate in contrast to leaf seven which is almost flat. Leaf length as well as the petiole length increases with age, dependent upon degree of maturity of the leaf. All leaves collected were as close as possible in stage of maturity so that the variation found is comparable. This group of leaves (Fig. 23) shows the large amount of leaf variability found in the Molino Canyon area. Fig. 22. Variation of greenhouse-grown Yauauelinia plants from San Carlos area. Fig. 23• Variation of greenhouse-grown Vauauelinia leaves from Molino Canyon area. 35 Figure 24 compares leaves from four different study- areas. From left to right, top row in this figure, leaves four, one, and six are from the.El Capitan area; leaves three, six, and seven from San Carlos; leaves, bottom row, two, five, and four from the Baboquivari Canyon area; and leaves five, one, and three from Organ Pipe. The leaves of each area show morphological variability, but a certain amount of genetic unity is indicated. The San Carlos and El Capitan Canyon area leaves have long petioles, and the Organ Pipe and Baboquivari area leaves have short ones. Leaf stipules vary in size. Those of the Baboquivari Canyon area are approximately 5 mm in length and width. In the El Capitan Canyon area, the leaves have almost no stipules. Width of leaf varies from approximately 22 mm in the San Carlos area to approximately 5 mm in the Organ Pipe area. Number of spines on leaf margins varies from small and numerous in the San Carlos area to large and few in the Organ Pipe area. Leaf length xiras also found to be variable, but an adequate sample was difficult to obtain because young plants have no terminal clusters (Fig. 21). Photographs were taken (Figs. 25 > 26, 27) from im­ mediately above the plants in order to show leaf length and

width, and spines. Figure 25 9 #31$5, is of a Vauquelinia plant from the Organ Pipe area; Figure 26, #3334, Molino Canyon area; and Figure 27, #3268, of the San Carlos area. (The numbers refer to the author's personal collections.) Fig. 24. Variation of greenhouse-grovm Vauauelinia leaves from El Capitan, San Carlos, Baboquivari, and Organ Pipe areas. El Capitan: upper left, 4» 1» 6 Baboquivari: lower left, 2, 5, 4 San Carlos: upper right, 3, 6, 1 Organ Pipe : bottom right, 5, 1, Fig. 25• Greenhouse-grown Vauauelinia #31&5 from Organ Pipe area. IF-

Fig. 26. Greenhouse-grovm Vauouelinia #3334 from Mblino Canyon area.

00- CO- Fig. 27• Greenhouse-grown Vauquelinia #3263 from San Carlos area.

vOCO- 90 The three figures show the variability of leaf range of the Vauquelinia californica in Arizona. Figure 25, Organ Pipe area, shows a plant with long narrow leaves. The leaves have fewer spines, are almost retrorse and margins tend to be revolute. This plant has leaves which resemble the fossil, Vauquelinia liniara (MacGinitie, 1953), which was obtained from the Florissant fossil beds. Figure 26 shows a Molino Canyon area plant xvith wider leaves than those of the Organ Pipe plant, Figure 25, but narrower than the leaves of the San Carlos area plant, Figure 27. The leaves in Figure 26 are almost double serrate and are undulate. Figure 27 of the San Carlos area plant shows the leaves to be the widest of the three with numerous spines and almost flat.

Laboratory Analyses Materials collected and data recorded in the field were analyzed in the laboratory at The University of Arizona. The statistical analyses for all data were accomplished on the CDC 6400 computer.

Length of Leaves The leaf length grand mean for all study areas was 102.46 mm. Mean leaf length ranged from S3.93 mm in the Molino Canyon area to 110.13 mm in the Organ Pipe area (Table 12). TABLE 12 Leaf Length Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean

Quadrant NE SE SW mi Mean.of Area (mm) Each Area Organ Pipe 110.08 106.40 110.33 113.13 a 110.13* Baboquivari Canyon 103.54 103.34 104.92 101.22 103.25 Molino Canyon 35. 56 3l.93 37.30 30.33 33.93 El Capitan Canyon 111.34 106.53 109.14 107.33 a 103.36* San Carlos 101.22 99.32 96.74 100.74 99.50 Mormon Flat 102. 34 110.12 111.23 112.12 a 109.09* Grand Quadrant Mean 102. 51 101.29 103.46 102. 53 Mean 102.46

^Means with same letter dp not differ significantly from each other. (Probability level = .05' 92 Quadrant mean for leaf length for all areas ranged from 101.29 in the SE quadrant to 103.46 in the SW quadrant, a difference of 1.17 mm (Table 12). The analysis of variance for leaf length (Table 13) shows a significant difference between areas, a highly- significant difference for quadrats within an area, and a highly significant difference also between quadrants within quadrats in an area. DuncanTs new multiple range test of area means indicates that leaf lengths do not differ signif­ icantly between Organ Pipe, El Capitan Canyon, and Mormon Flat. However, these areas do differ significantly from the remaining areas and, furthermore, all remaining areas are different from one another (Table 12).

Width of Leaves The leaf width grand mean for all study areas is 17.21 mm (Table 14). The narrowest leaves are from the Organ Pipe area with a mean of 8.68 mm which is significantly different from the mean of other areas. The widest leaves are from the San Carlos area with a mean of 25-49 mm. The dif­ ference of 16.62 mm is almost twice that of the ividth of the Organ Pipe area leaves. The quadrant means of leaf widths for all areas are almost equal. The largest is 17.29 mm for the SW quadrant and the smallest is 17.12 mm for the NW quadrant, a difference of only .17 mm (Table 14)• TABLE 13 Analysis of Variance for Leaf Length"*"

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Areas 5 99,309.43 19,861.89 2.91* Tree/Area 24 163,253.10 6,802.21 23.55** Quadrant/Tree/Area 90 25,606.42 284.51 2.10** . Leaf/Quadrant/ Tree/Area 1,080 146,089.30 .135.26

TOTAL 1,199 434,258.31 ^Significant (P = .05) **Highly significant (P = .01)

^Significant values determined by tables in Robert G. D. Steel and James H. Torrie's Principles and Procedures of Statistics (New York: McGraw- Hill Book Company, Inc.), 19&0. TABLE 14 Leaf Width Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean

! Quadrant NE SE SW NW Area (mm) Mean of Each Area

Organ Pipe 8.66 8..80 8,48 8.76 8.68 Baboquivari Canyon 13.70 13..50 13.76 13.58 d 13.64* Molino Canyon 15.22 15..42 15.16 15.14 cd 15.24* El Capitan Canyon 18.50 19.,18 19.16 19.52 be 21.14* San Carlos 25.98 25-.10 25.46 25.42 a 25.4^ Mormon Flat 20.86 21..68 21.34 20.66 ab 19.09* Grand Quadrant Mean 17.15 17..28 17- 29 17.12 Mean 17.21

*Means with same letters do not differ significantly from each other. (Probability level = .05) 95 The analysis of variance for leaf width shows that variation between areas is highly significant. The variation between quadrats within an area and between quadrants within quadrats is also highly significant (Table 15)• Examination of the results shows that very small differences are significant within areas, whereas larger differences are observed in the over-all means of areas.

Petioles The grand mean for petiole lengths for all study areas is 13.62 mm. The area having the shortest petiole lengths, 10.$2 mm (Table 16), is the Organ Pipe area. The El Capitan area has the greatest petiole mean length, 17.56 mm. The difference between these extremes is 6.74 mm. Quadrant petiole length means in all areas are almost equal, with a difference of only .53 mm. The longest petioles, 13.$3 mm> occur in the SW quadrant. The shortest, 13.57 mm, occur in the SE quadrant. The analysis of variance for area leaf petioles re­ veals that significant difference exists among these means (Table 17)• The variation between quadrats within an area is highly significant and the variation between quadrants within quadrats in an area is highly significant.

Spines The grand mean for number of leaf spines per cm of length is 4.24 (Table 1$). The Organ Pipe area has the TABLE 15 Analysis of Variance for Leaf Width

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Areas 5 35,405.1$ 7,031.03 17.55** Tree/Area 24 9,679.70 403.32 30.$$** Quadrant/Tree/Area 90 1,176.00 13.06 1.34**

Leaf/Quadrant/ • Tree/Area 1,080 7,640.20 7.07 TOTAL . 1,199 53,901.0$

^Highly significant (P = .01) TABLE 16 Petiole Length Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean

Quadrant NE SE SW NW Mean of Area (mm) Each Area

Organ Pipe 10.94 10.58 11.10 10.66 b 10.82* Baboquivari Canyon 12.80 13.26 13.42 13.10 b 13.14* Molino Canyon 11.78 11.32 12.64 10.86 b 11.65* El Capitan Canyon IS.76 17.32 17.14 17.04 a 17.56* San Carlos 15.32 14.70 14.84 14.82 ab 14.92* Mormon Flat 13.12 14.26 13.84 13 .32 ab 13 .63"" Grand Quadrant Mean 13.78 13.57 13.83 13 .30 Mean 13.62

Cleans with same letters do not differ significantly from each other. (Probability level = .05) TABLE 17 Analysis of Variance for Leaf Petioles

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Areas 5 - 5,839*94 1,167.98 3.56* Tree/Area 24 7,856.07 327.33 25.17** Quadrant/Tree/Area 90 . 1,174.47 13.04 2.18** Leaf/Quadrant/ Tree/Area 1,080 6,447.50 5.96

TOTAL 1,199 21,317.99

^Significant (P = .05) ^Highly significant (P = .01)

vO 03- TABLE Id Leaf Spine Means of Each Area, Each Quadrant, Each Quadrant within Each Area, and Grand Mean

Quadrant NE SE S\'l NW Mean of Area 'number oer cm of length) Each Area •JU Organ Pipe l.k& 1.54 1.58 1.5S b 1.54" Baboquivari Canyon 2.2$ 2.30 2.30 2.26 b 2.2a* Molino Canyon 4.74 5.25 4.70 4.36 a 4.77* El Capitan Canyon 6.40 5.56 6.10 5.33 a 5.9a* San Carlos 5.46 6.10 5.60 6.04 a 5.30* Mormon Flat 5.00 5.20 5.12 5.04 a 5.09* Grand Quadrant Mean 4.22 4.33 4.23 4.19 Mean 4.24

Means with same letters do not differ significantly from each other (Probability level = .05) 100 smallest mean with 1.54 spines which is not significantly- different from that of the Baboquivari area, its neighboring area. These two areas do differ from the other areas with respect to number of leaf spines (Table 1$). The El Capitan Canyon area has the largest mean number of spines, 5«9&. Quadrant means varies only slightly with the SE quadrant having 4-33 and the NW quadrant 4.19 spines. The mean dif­ ference is .14 for the two quadrants. The leaf spine analysis of variance (Table 19) gives a highly significant difference between areas. The quadrats* variation within an area is also highly significant, as is the variation of quadrants within quadrats of an area.

Leaf Analyses Summary Leaf characteristics were found to be significantly variable among the study areas. Leaf length, width, and number of spines per linear cm of leaf margin along with petiole length showed some pattern of variation. Leaf width was significantly lower for the Organ Pipe area as compared to all other areas. The number of spines per cm was least for Organ Pipe but these did not show a statistically signif­ icant difference from the spines of those in the neighboring area, Baboquivari Canyon. Length of leaves was approximately the same for three of the six areas. Organ Pipe, El Capitan, and Mormon Flat. Although Organ Pipe had the greatest mean, it was not TABLE 19 Analysis of Variance for Leaf Spines

Degrees of Sum of • Source of Variation Freedom Squares Means Squared F

Areas 5 3,513.37 702.67 7.52** Tree/Area 24 2,240.43 93.35 11.27** Quadrant/Tree/Area 90 745.37 S.2S 2.54** Leaf/Quadrant/ Tree/Area 1,0 SO 3,517.30 3.25 TOTAL 1,199 10,016.47

••Highly significant (P = .01) 102 statistically significant from that of the other two areas. Variability of leaf length was also noted to occur with respect to quadrant, but no pattern for this variation can be determined from the data (Table 12). Leaf petiole length had the least variability of all leaf characteristics among areas. The range was from 10.$2 to 17.56 mm for Organ Pipe and Baboquivari areas, respectively. No distinct break was evident in the range of area means. Therefore, a separation of areas using this taxonomic variable could not be accomplished on a statistical basis. Correlation analysis was performed on all leaf data (Table 20). The highest correlation, .496, was petiole length versus leaf length, and the lowest was .100 petiole length versus spine number.

Seeds Vauquelinia californica seed measurements included over-all seed length, seed body length, seed body width, and wing width. Area means for the four variables were greatest for the Organ Pipe area. Molino Canj^on was second to Organ Pipe in size of means for the four variables (Table 21). Seed length means ranged from 163.56 to 205.90 units (40 units = 1 mm) and were significantly different (Table 22). Further analysis indicated that Baboquivari Canyon and Mormon Flat mean seed lengths did not differ significantly, but all other area comparisons were significantly different. TABLE 20 Correlation Matrix for Leaf Data

Variable Petiole Width Length Spines

O C* 1 Spines .100* .307** • djoy * 1.000**

Length .496** •144** 1.000**

Width .45 5** 1.000**

Petiole 1.000**

^Significant (P = .05) **Highly significant (P = .01) 1200 observations TABLE 21 Means and Grand Means for Seed Length, Seed Body Length, Seed Wing Width, and Seed Body Width

Area Measure­ Organ Baboquivari Molino El San Mormon Grand ment Pipe Canyon Canyon Capitan Carlos Flat Mean

Seed length 205.90 a 132.02* 197.32 163.56 176.60 a 131.25* 134*44 Seed body length 109.52 102.22 106.03 a 90.10* a 39.93* 93.90 93.63 Seed wing width 56.24 43.02 50.16 a 43 •66'"' a 44.29* 49.15 43.53 Seed width 47.34 a 44*60 a 45.04* 36.66 35.44 39.60" 41• 44

."""Means with same letter do not differ significantly from each other. (Probability level = .05)

Note: AjO units of measurement = 1 mm. TABLE 22 Analysis of Variance for Seed Length

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Between areas 5 56,574.17 11,314.83 3.79* Between trees/Area 20 59,5&L.52 2,979.07 31.47** Remainder 234 22,150.90 94.66 TOTAL 259 13^,306.59

•Significant (P = .05) ••Highly significant (P = .01) 106 Seed body length for the six study areas ranged from S9.9S to 109.52 units with the El Capitan and San Carlos area means being nonsignificant (Tables 21 and 23)• Seed wing width differed significantly•among areas with a range in values of 43.66 to 56.24 units. A test of these means indicated that the El Capitan and San Carlos areas were not significantly different at P = .05 (Tables 21 and 24). Seed width varied from 35.44 to 47.34 units for area means which were significantly different. Baboquivari Canyon and Molino Canyon area means were not significantly different at P = .05 using Duncan's new multiple range test (Tables 21 and 25). In all cases, a significant variation was present for trees vathin each area (Tables 22, 23, 24, 25). There­ fore, these mean squared terms were used to calculate the standard error of the variable means for areas. The use of these statistical procedures did not identify any particular area as being separated from all others in seed characteristics. Correlation analysis was performed on seed data (Table 26). All correlations were highly significant; seed length versus seed body length had the highest correlation, .824. Seed width versus wing width was second with .727. The lowest correlation was wing width versus seed body length. TABLE 23 Analysis of Variance for Seed Body Length

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Between areas 5 17,004.11 3,400.82 2.94*

Between trees/Area 20 23,122.11 1,156.10 39.75** Remainder 234 6,306.30 29.08

TOTAL 259 46,932.52 ^Significant (P = .05) **Highly significant (? = .01) TABLE 24 Analysis of Variance for Seed Wing Width

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Between areas 5 5,222.34 1,044«46 5.2$**

Between trees/Area 20 3,951.93 197.59 15.97**

Remainder 234 2,903.68 12.37

TOTAL 259 12,032.95 ^Highly significant (P = .01) TABLE 25 Analysis of Variance for Seed Width

Degrees of Sum of Source of Variation Freedom Squares Means Squared F

Areas 5 5,795.53 1,159.10 9.51**

Between trees/Area 20 2,437.4$ 121.37 16.99**

Remainder 234 1,679.60 7.17

TOTAL 259 9,912.61 ••Highly significant (P = .01)

o vO TABLE 26 Correlation Matrix for Seed Data

Seed Seed body V/ing Seed Variable length length width width

Seed width • 5//£"*"7 w .630** .727** 1.000**.

Wing width .544** .529** 1.000**

Seed body length •$24** 1.000**

Seed length 1.000**

**Highly significant (P = .01) 260 observations Ill

Herbarium Specimens Many herbarium specimens were examined during the study and among these the earliest Vauquelinia californica specimens came from the collections made in 1&&L by C. G. Pringle, J. G. Lemmon, and C. R. Vasey. These specimens were among the many borrowed from the institutions listed in Methods and Materials. In addition, the author studied his own collection of Vauquelinia californica (made over a period of six years) consisting of both sterile and fertile specimens from different areas in Arizona. Morphological features of leaves from the different areas were studied. Leaf length and xvidth, petiole length, spine number, and pubescence were different for leaves from different areas. Herbarium specimens showed that the Organ Pipe area leaves were the longest and narrowest, that the3>- had fewer spines and were more pubescent than those of any of the other study areas. Collection of leaves from the Gila and Salt River areas showed them to be wider and with more spines which were smaller. The leaves from these two areas were almost glabrous. Inflorescence size varied from largest in the Gila and Salt River areas to smallest in the Organ Pipe area. 112

Species Density An analysis of variance for species density showed that twenty-one species (Table 27) varied significantly' between areas. One of these species occurred in 5 areas, four in 4 areas, eight in 3 areas, three in 2 areas, and five species in 1 area only. Cercidium microphyllum (Table 27) had a highly significant density mean because of its occurrence in only one area. A number of significant values were based upon the nonoccurrence of the same species in one or several areas (Table 27). The quadrant density means for species which showed significant variation between areas are listed in Table 28. All species occurred in the four quadrants of each quadrat except Commelina erecta, Metastelma arizonicum, Notholaena aurea, and Sphaeralcea Fendleri. Table 29 gives the area density means for species which showed significant variation between quadrats. Of the total fifty-one species, one occurred in all 6 areas, two in 5 areas, five in 4 areas, seven in 3 areas, fourteen in 2 areas, and twenty-two species in only larea. The quadrant density means for species which showed significant variation between quadrats are listed in Table 30. Of a total of fifty-one species, twenty-three were found in all 4 quadrants, twelve in 3 quadrants, and sixteen in only 2 quadrants. TABLE 27

Area Density Mean of Species Showing Significant Variation between Areas

l Areas Organ Baboauivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Abutilon parvulum 0.250 0.000 0.000 0.425 0.000 0.075 Aloysia Wrightii 0.225 0.000 0.000 0.250 0.400 0.000 Andropogon barbinodis 0.000 0.000 0.325 0.000 0.050 0.100 Arabis perennans 0.000 0.000 0.000 1.150 0.475 2.150 Cercidium microphyllum 0.000 0.000 0.000 0.000 0.000 0.375 Cheilanthes Lindheimeri 0.400 3.400 2.100 0.025 0.000 0.000 Commelina erecta var. crispa 0.000 0.150 0.000 0.000 0.000 0.000 Dasylirion Wheeleri 0.000 0.250 0.100 0.050 0.025 0.000 Dodonaea viscosa 0.175 0.150 0.000 0.050 0.350 0.050 Echeveria Collomae 0.000 • 0.000 0.000 0.000 0.000 0.400 Echinocereus fasciculatus var. Boyce-Thompsonii 0.000 0.000 0.000 0.325 0.175 0.150 Ephedra fasciculata 0.050 0.000 0.000 0.000 0.125 0.375 Eriogonum fasciculatum 0.050 0.000 0.000 0.000 0.000 0.250 TABLE 27—Continued

Erythrina flabelliformis 0.000 0.200 0.150 0.000 0.000 0.000 Metastelma arizonicum 0.000 0.000 0.000 0.025 0.000 0.100 Muhlenbergia Porteri 0.175 0.575 0.000 0.025 0.375 0.000 Notholaena aurea 0.000 0.175 0.000 0.000 0.000 0.000 Opuntia acanthocarpa var. major 0.000 0.000 0.000 0.250 0.150 0.425 Pellaea Jonesii 0.025 0.000 0.050 0.025 0.275 0.000 Porophyllum gracile 0.000 0.250 0.000 0.025 0.000 1.075 Sphaeralcea Fendleri 0.000 0.000 0.000 0.350 0.000 0.000 TABLE 23

Quadrant Density Mean of Species Showing Significant Variation between Areas

Quadrant Species m SE SW NW

Abutilon parvulum 0.150 0.250 0.067 0.033 Aloysia Wrightii 0.133 0.133 0.217 0.100 Andropogon barbinodis 0.033 0.133 0.117 0.033 Arabis perennans 1.033 0.417 0.650 0.417 Cercidium microphyllum 0.050 0.050 0.067 0.033 Cheilanthes Lindheimeri 1.233 1.800 0.633 0.233 Coramelina erecta var. crispa 0.017 0.000 0.033' 0.000 Dasylirion Wheeleri 0.033 0.067 0.033 0.100 Dodonaea viscosa 0.233 0.100 0.117 0.067 Echeveria Collomae 0.033 0.100 0.067 0.067 Echinocereus fasciculatus var. Boyce-Thompsonii 0.033 0.133 0.150 0.117 Ephedra fasciculata 0.167 0.050 0.033 0.067 Eriogonum fasciculatum 0.017 0.017 0.133 0.033 TABLE 2&--Continued

Erythrina flabelliformis 0.050 0.117 0.017 0.050 Metastelma arizonicum 0.017 0.017 0.000 0.050 Muhlenbergia Porteri 0.217 0.163 0.150 0.217 Notholaena aurea 0.017 0.033 0.000 0.067 Opuntia acanthocarpa var. major 0.033 0.100 0.150 0.067 Pellaea Jonesii 0.017 0.133 0.033 0.067 Porophyllum gracile 0.150 0.200 0.333 0.217 Sphaeralcea Fendleri 0.000 0.033 0.167 0.033 TABLE 29 Area Density Mean of Species Showing Significant Variation between Quadrats

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Agave Schottii 0.050 1.750 5.550 0.000 0.000 0.000 Aristida adscensionis 0.000 0.000 0.000 2.625 0.000 0.050 Aristida barbata 0.000 0.000 0.275 0.000 0.000 0.000 Aristida Fendleriana 0.000 0.000 0.000 0.200 0.000 0.000 Aristida hamulosa 0.000 0.125 0.000 0.000 0.000 0.000 Aristida Parishii 0.000 0.000 0.000 0.000 0.000 0.100 Artemisia ludoviciana 0.700 1.000 0.475 0.175 .1.575 0.000 Ayenia pusilla 0.000 0.100 0.150 0.000 0.050 0.250 Berberis trifoliolata 0.000 0.000 0.000 0.150 0.000 0.000 Bommeria hispida 0.075 0.000 0.175 0.000 0.000 0.000 Bouteloua xiliformis 0.000 0.275 1.600 0.275 0.000 0.175 Bouteloua hirsuta 0.000 0.225 0.725 0.125. 0.000 0.000 Calliandra humilis 0.000 0.275 1.625 0.775 0.000 1.250 TABLE 29—Continued. Area Density Mean of Species Showing Significant Variation between Quadrats

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Carex sp. 0.000 0.275 0.000 0.000 0.000 0 .075 Cassia Covesii 0.000 0.000 0.000 0.050 0.000 0.000 Ceanothus Greggii 0.000 0.000 0.000 0.200 0.000 0 .150 Cercocarpus montanus 0.000 0.000 0.000 0.050 0.000 0.000 Chrysopsis hispida 0.000 0.000 0.000 0.000 0.000; 0.125 Condalia lycioides 0 .000 0.000 0.000 0.125 0.000 0.000 Evolvulus pilosus 0 .000 0.000 0.000 0.050 0.000 0.000 Galactia Wrightii 0 .000 0.000 0.075 0.000 0.000 0.000 Gossypium Thurberi 0 .000 0.650 0.050 0.000 0.000 0.000 Halimolobos diffusus 0 .000 0.100 0.000 0.000 0.000 0,.000 Heteropogon contortus 0 .000 0.150 0.600 0.150 0.000 0 .000 Janusia gracilis 0 .050 0.000 0.025 0.000 0.000 0.000 Jatropha cardiophylla 0 .000 0.000 0.075 0.000 0.000 0 .000 Lagascea decipiens 0 .000 0.275 0.000 0.000 0.000 0.000 Leptochloa dubia 0 .000 0.525 0.250 0.000 0.050 0 .000 TABLE 29—Continued. Area Density Mean of Species Showing Significant Variation between Quadrats Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Lycurus phleoides 0.000 0.100 0.100 0.000 0.000 0.000 Menodora scabra 0.150 0.000 0.000 0.000 0.100 0.000 Mimosa biuncifera 0.025 0.000 0.000 0.400 0.000 0.625 Muhlenbergia Emersleyi 0.000 0.100 0.075 0.075 0.000 0.000 Nolina microcarpa 0.000 0.175 0.000 0.025 0.000 0.000 Notholaena sinuata var. integerrima 0.025 0.000 0.000 0.125 0.000 0.000 Opuntia phaecantha var. discata 0.000 0.150 0.000 0.200 0.025 0.050 Opuntia versicolor 0.000 0.000 0.125 0.000 0.000 0.000 Opuntia violacea var. santa-rita 0.000 0.050 0.000 0.000 0.000 0.000 Panicum arizonicum 0.000 0.000 0.000 2.200 0.000 0.750 Panicum capillare 0.000 0.350 0.000 0.000 0.000 0.100 Panicum Hallii 0.000 0.000 0.000 0.350 0.000 0.000 Pellaea limitanea 0.350 0.425 0.775 0.125 0.200 0.125 1 TABLE 29—Continued* Area Density Mean of Species Showing Significant Variation between Quadrats

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Penstemon pseudospectabilis 0.075 0.000 0.000 0.050 0.100 0.000 Psilostrophe Cooperi 0.000 0.000 0.000 0.050 0.000 0.000 Rhus trilobata 0.000 0.100 0.000 0.000 0.000 0.000 Rhynchosia texana 0.100 0.575 0.000 0.000 0.000 0.000 Rivina humilis 0.050 0.000 0.000 0.000 0.000 0.000 Selaginella arizonica 0.350 0.000 0.000 2.$00 0.125 4.250 Simmondsia chinensis 0.750 0.050 0.000 0.275 0.525 0.475 Stipa speciosa 0.050 0.000 0.000. 0.575 0.000 0.000 Tragia nepetaefolia 0.275 0.000 0.000 0.000 0.000 0.000 Yucca baccata 0.000 0.000 0.000 0.125 0.000 0.000

H TO O TABLE 30 Quadrant Density Mean of Species Shovang Significant Variation between Quadrats

Quadrant Species NE SE SW NW

Agave Schottii 1.017 1.317 1.117 1.450 Aristida adscensionis 0.417 0.500" 0.333 0.533 Aristida barbata 0.033 0.000 0.050 0.100 Aristida Fendleriana 0.000 0.017 0.067 0.050 Aristida hamulosa OeOOO 0.050 0.033 0.000 Aristida Parishii 0.000 0.050 0.017 0.000 Artemisia ludoviciana 0.333 0.500 0.733 0.450 Ayenia pusilia 0.100 0.150 0.050 O.O67 Berberis trifoliolata 0.017 0.033 0.017 0.033 Bommeria hispida 0.033 0.017 0.033 0.033 Bouteloua filiformis 0.450 0.250 O.3S3 0.467 Bouteloua hirsuta 0.033 0.150 0.267 0.217 Calliandra humilis 0.333 0.767 0.450 0.567 Carex sp. 0.150 0.033 0.000 0.000 TABLE 30—Continued. Quadrant Density Mean of Species Showing Significant Var­ iation between Quadrats Quadrant Species m SE SW W1

Cassia Covesii 0.000 0.000 0.017 0. "'.7 \ - 0 0 U Ceanothus Greggii 0 0.067• 0.100 0.017 Cercocarpus montanus 0.017 " 0.017- 0.000 0.000 Chrysopsis hispida 0.033 0.050 0.000 0.000 Condalia lycioides 0.000 0.033 0.050 0.000 Evolvulus pilosus 0.000 0.000 0.017 0.017 Galactia Wrightii 0.033 0.000 0.017 0.000 Gossypium Thurberi 0.067 0.0S3 0.033 0.2S3 Halimolobos diffusus • 0.017 0.017 0.017 0.017 Heteropogon contortus 0.100 0.067 0.300 0.133 Janusia gracilis 0.017 0.017 0.000 0.017 Jatropha cardiophylla 0.000 0.033 0.000 0.017 Lagascea decipiens 0.067 0.017 0.033 0.067 Leptochloa dubia 0.117 0.083 0.250 0.100 Lycurus phleoides 0.000 0.050 0.033 0.000 TABLE 30—Continued. Quadrant Density Mean of Species Showing Significant Var­ iation between Quadrats Quadrant Species NE SE SW m ' Kenodora scabra O.O83 0.033 0.050 0.000 Mimosa biuncifera 0.200 0.100 0.033 0.367 Muhlenbergia Emersleyi 0.067 0.050 0.050 0.000 Nolina microcarpa 0.017 0.017 0.000 0.100 Notholaena sinuata var. integerrima 0.050 0.017 0.017 0.017 Opuntia phaecantha var. discata 0.067 0.017 0.083 0.117 Opuntia versicolor 0.017 0.050 0.017 0.000 Opuntia violacea var. santa-rita 0.000 0.000 0.017 0.017 Panicum arizonicum 0.683 0.683 0.050 0.550 Panicum capillare 0.117 0.100 0.000 0.083 Panicum Hallii 0.100 0.000 0.133 0.000 Pellaea limitanea 0.650 0.350 0.267 0.067 Penstemon pseudospectabilis 0.033 0.000 0.067 0.050 Psilostrophe Cooperi 0.000 0.017 0.000 0.017 TABLE 30—Continued. Quadrant Density Mean of Species Showing Significant Var­ iation between Quadrats Quadrant Species NE SE sw NW

Rhus trilobata 0.033 0.017 0.017 0.000 Rhynchosia texana 0.000 0.250 0.100 0.100 Rivina humilis 0.017 0.000 0.000 0.017 \ f 0 0 L Selaginella arizonica . 2.083 1 0.450 1.000 Simmondsia chinensis 0.417 0.450 0.233 0.267 1 \ — ( O T Stipa speciosa . 0.183 0 0.033 0.050 \ O " H O r Tragia nepetaefolia . 0.000 0 0.067 0.033 Yucca baccata 0.000 0.033 0.050 0.000

JO •P- 125 The area density means for species which showed significant variation between areas and also between quadrats are given in Table 31* One species occurred in all 6 areas, two in 5 areas, six in /+ areas, two in 3 areas, five in 2 areas, and eleven species in 1 area. Table 32 gives the quadrant density means of the species which showed significant variation between areas and also between quadrats. Of the total twenty-seven species, all except two, Aristida Wrightii and Lotus rigidus, occurred in at least one of the four quadrants. Area and quadrant density means of species which showed no significant variation between areas, quadrats, and quadrants are recorded in Tables 33 and 34. Of the forty-five species listed, Crossosoma Bigelovii, Krameria parvifolia, Mammillaria microcarpa, Notholaena sinuata, and Pellaea longimucronata are of interest. Only Crossosoma Bigelovii, Notholaena sinuata, and Pellaea longimucronata occurred in all of the four different quadrants. Notholaena sinuata and Pellaea longimucronata occurred in four different areas, and Crossosoma Bigelovii occurred in three different areas. Table 35 lists each area and number of species with source of significance which occurred in each area. Both Organ Pipe and Baboquivari had eight species which were significant between areas; however, only three of these were common to both areas. Therefore, thirteen different species occurred in the two areas. TABLE 31 Area Density Mean of Species Showing Significant Variation between Areas and Also between Quadrats

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Acacia Greggii 0 oOOO 0.000 0.025 0.175 0.175 0.550

Agave Palmeri 0.000 0.000 0.225 0.250 0.375 0.000 Anisacanthus Thurberi 0.000 0.450 0.000 0.000 0.000 0.000 Aristida ternipes 0.025 0.300 0.500 0.100 0.000 0.000 Aristida Wrightii 0.000 0.000 0.000 0.000 0.350 0.000 Bouteloua curtipendula 1.275 0.750 2.500 3.725 3.625 0.475 Brickellia atractyloides 0.000 0.000 0.000 0.000 0.475 0.000 Canotia holacanths 0.000 0.000 0.000 0.000 0.175 0.000 Dalea formosa 0.000 0.000 0.175 2.050 0.125 0.000 Eragrostis intermedia 0.000 1.100 0.300 0.000 0.000 0.000 Eriogonum Wrightii 0.050 0.400 0.175 0.125 0.000 0.825 Eupatorium pauperculum 0.425 0.000 0.000 0.000 0.000 0.000

Euphorbia melanadenia 0.150 0.025 0.400 0.000 0.000 1.100 TABLE 31—Continued Eysenhardtia polystachya 0.000 0.000 0 000 0.000 I Fouquieria splendens 0.375 0.325 0 000 0.025 I Galium stellatum 0.000 0.225 0 550 0.150 1 Gutierrezia lucida 0.000 3.#25 0 225 0.025 Haplopappus laricifolius 1.-475 0.000 0 000 0.000 Haplopappus spinulosus 0.000 0.000 0 000 0.750 Jacobinia ovata 0.000 0.000 0 000 0.000 Lotus rigidus 0.300 0.000 0 000 0.200 Salvia pinguifolia 0.000 0.475 0 000 0.000 Selaginella rupincola 10.400 0.000 0 000 0.000 Sphaeralcea laxa 0.000 0.125 0 000 0.400 Trichachne californica 0.125 0.000 0 000 0.000 Tridens muticus 0.000 1.550 0 850 1.700 Viguiera deltoidea 0.000 0.000 0 000 0.S25 TABLE 32 Quadrant Density Mean of Species Showing Significant Variation between Areas and Also between Quadrats

Quadrant Species NE SE sw NW

Acacia Greggii 0.217 0.183 0.117 0.100 Agave Palmeri 0.100 0.167 0.117 0.183 Anisacanthus Thurberi 0.083 0.083 0.100 0.033 Aristida ternipes 0.167 0.117 0.150 0.183 Aristida Wrightii 0.133 0.083 0.017 0.000 Bouteloua curtipendula 2.767 1.683 2.350 1.433 Brickellia atractyloides 0.117 0.050 0.100 0.050 Canotia holacantha 0.033 0.033 0.017 0.033 Dalea formosa 0.433 0.250 0.350 0.533 Eragrostis intermedia 0.233 0.200 0.250 0.250 Eriogonum Wrightii 0.183 0.217 0.267 0.383 Eupatorium pauperculum 0.017 0.033 O.O83 0.150

Euphorbia melanadenia 0.417 0.233 0.233 0.233 Eysenhardtia polystachya O.O83 0.100 0.050 0.067 TABLE 32—Continued Fouquieria splendens 0.150 0.150 0.050 0.183 Galium stellatum 0.200 0.233 0.117 0.300 Gutierrezia lucida 1.000 0.700 0.433 0.733 Haplopappus laricifolius 0.367 0.367 0.350 0.450 Haplopappus spinulosus 0.200 0.133 0.067 0.100 Jacobinia ovata 0.167 0.150 0.117 0.200 Lotus rigidus 0.033 0.133 0.117 0.000 Salvia pinguifolia 0.150 0.050 •0.067 0.050 Selaginella rupincola 1.333 1.917 1.533 1.600 Sphaeralcea laxa 0.033 0.150 0.067 0.050 Trichachne californica 0.033 0.017 0.017 0.017 Tridens muticus 1.217 0.567 0.250 0.733 Viguiera deltoidea 0.117 0.117 0.300 0.133 TABLE 33 Area Density Mean of Species Showing No Significant Variation between Areas, Quadrats, and Quadrants

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Acacia constricta .000 .000 .000 .050 .000 .000 Agave deserti .075 .000 .000 .000 .000 .000 Agave Toumeyana .000 .000 .000 .075 .400 .000 Arctostaphylos pungens .000 .000 .025 .000 .000 .000 Aristida pansa .000 .000 .000 .025 .000 .000 Asclepias angustifolia .000 .000 .025 .000 .000 .000 Baccharis glutinosa .000 .000 .000 .200 • .000 .000 Bouvardia glaberrima .000 .050 .000 .000 .000 .000 Celtis pallida .000 .000 .000 .000 .025 .000 Cereus giganteus .000 .000 .025 .000 .000 .000 Cheilanthes tomentosa .025 .000 .075 .000 .000 .000 Commelina erecta .125 .000 .000 .000 .000 .000 Crossosoma Bigelovii .000 .075 .050 .000 .000 .150 Draba cuneifolia .000 .000 .000 .100 .000 .000 TABLE 33—-Continued

Areas Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat

Elyonurus barbiculmis .000 .025 .000 .000 .000 .000 Encelia farinosa .000 .000 .000 .000 .000 .050 Euphorbia arizonica .000 .025 .000 .000 .000 .000 Ferocactus acanthodes var. LeContei .000 .000 .000 .000 .100 .050 Ferocactus Wislizenii .000 .000 .050 .000 .000 .000 Galium microphyllum .000 .025 .000 .000 .000 .000 Hibiscus Coulteri .000 .000 .000 .000 .000 .125 Hilaria Belangeri .000 .000 .000 .075 .000 .000 Krameria Grayi .000 .075 .000 .125 .000 .000 Krameria parvifolia .000 .250 .400 .000 .025 .000 Lycium Berlandieri. .000 .000 .000 .000 .000 .075 Malvastrum bicuspidatum .050 .000 .000 .000 .000 .000 Mammillaria microcarpa .000 .175 .275 .050 .000 .000 Melampodium leucanthum .000 .000 .025 .150 .000 .000 Muhlenbergia monticola .125 .200 .000 .000 .000 .000 TABLE 33—Continued

Areas ' Organ Baboquivari Molino El San Mormon Species Pipe Canyon Canyon Capitan Carlos Flat Nissolia Schottii .000 .300 .000 .000 .000 .000 Notholaena sinuata .150 .350 .500 .225 .000 .000 Opuntia phaeacantha var. laevis .000 .000 .050 .000 .000 .000 Opuntia phaeacantha var. major .025 .000 .000 .000 .000 .000 Oxalis stricta .000 .025 .000 .000 .000 .000 Pellaea longimucronata .125 .525 .050 .000 .150 .000 Quercus oblongifolia .000 .025 .000 .000 .000 .000 Quereus reticulata .000 .025 .000 .000 .000 .000 Quercus turbinella .000 .000 .000 .100 .000 .000 Setaria macrostachya .025 .000 .000 .000 .000 .000 Stipa cornata .000 .000 .000 .025 .000 .000 Stipa neomexicana' .000 .000 .000 .025 .000 .000 Tribulus terrestris .000 .000 .000 .025 .000 .000 Trixis californica .000 .000 .025 .000 .000 .000 Yucca arizonica .000 .025 .000 .000 .000 .000 Zinnia pumila .000 .000 .000 .025 .000 .000 TABLE 34 Quadrant Density Mean of Species Showing No Significant Variation between Areas, Quadrats, and Quadrants

Quadrant * Species NE SE Sw NW

Acacia constricta .000 .000 .017 .017 Agave deserti .017 .000 .033 .000

Agave Toumeyana .017 .033 .133 .083 Arctostaphylos pungens .000 .000 .000 .017 Aristida pansa .000 .000 .017 .000 Asclepias angustifolia .000 .000 .000 .017 Baccharis glutinosa .033 .083 .017 .000 Bouvardia glaberrima .033 .000 .000. .000 Celtis pallida .017 .000 .000 .000 Cereus giganteus .000 .017 .000 .000 Cheilanthes tomentosa .017 ' .000 .050 .000 Commelina erecta .000 .050 .017 .017 Crossosoma Bigelovii .050 .033 .033 .067 Draba cuneifolia .000 .067 .000 .000 TABLE 34—-Continued Quadrant Species NE SE SW HW

Elynurus barbiculmis .000 .000 .000 .017 Encelia farinosa .017 .000 .017 .000 Euphorbia arizonica .000 .017 .000 .000 Ferocactus acanthodes var. LeContei .033 .000 .017 .000 Ferocactus Wislizenii .000 .017 .017 .000 Galium microphyllum .017 .000 .000 .000 Hibiscus Coulteri .033 .000 .000 .050 Hilaria Belangeri .000 .000 .000 .050 Krameria Grayi .050 .000 .000 .033 Krameria parvifolia .067 .033 .200 .000 Lycium Berlandieri .000 .050 .000 .000 Malampodium leucanthum .033 .000 .017 .017 Malvastrum bicuspidatum .000 .000 .033 .000 Mammillaria microcarpa .117 .150 .067 .000 Muhlenbergia monticola .017 .033 .033 .033 TABLE 34—Continued Quadrant Species NE SE SV7 NW

Nissolia Schotti .000 .000 .200 .000 Notholaena sinuata .333 .217 .033 .183 Opuntia phaeacantha var. laevis .000 .000 .017 .017 Opuntia phaeacantha var. major .000 .017 .000 .000 Oxalis stricta .000 .017 .000 .000 Pellaea longiraucronata .233 .050 .267 .017 Quercus oblongifolia .000 .000 .000 .017 Quereus reticulata .000 .017 .000 .000 Quercus turbinella .017 .050 ' .000 .000 Setaria raacrostachya .000 .000 .017 .000 Stipa comata .000 .000 .017 .000 Stipa neomexicana .000 .000 .000 .017 Tribulus terrestris .000 .017 .000 .000 Trixis californica .000 .017 .000 .000 Yucca arizonica .017 .000 .000 .000 Zinnia pumila .017 .000 .000 .000 TABLE 35 Analysis of Species Density and Their Source of Significance

Areas Organ Baboquivari Molino El San Mormon Source of Pipe Canyon Canyon ' Capitaii Carlos Flat significance (species) (species) (species) (species) (species) (species)

Between- areas 3 6 5 13 10 12 Between areas and also be­ tween quadrats 10 10 13 12 10 12 Between quadrats 15 23 13 27 9 15 , Non-significant ) (species) 9 16 13 15 5 5

TOTAL 42 57 49 67 34 44

U>H c^ 137

Association Analyses The Dice Index (Dice, 1945) as applied to the species (Table 36) showed ninety-five associations which were chosen from 20,592 combinations. The ninety-five associ­ ations were chosen because the species occurred together four or more times and because they had an association index of .500 or greater. It was thought by the author that plants which occurred together less than four times would not give as accurate data as desired. The index, as it was applied here, revealed associa­ tion between any two species. Bouteloua curtipendula, which had a density of 2.O5S, showed the greatest number of high percentage associations; Haplopappus laricifolius, with a density of .3^3, was second; and Artemisia ludoviciana and Calliandra humilis, each with a density of .654, were third. Plants itfhich showed the highest mutual association (Table 36), as determined from both values of Dicefs Index, were: Aristida adscensionis/Panicum arizonlcum Bouteloua hirsuta/Heteropogon contortus Dalea formosa/Gutierrezia lucida Haplopappus laricifolius/Selaginella rupincola Haplopappus spinulosus/Selaginella arizonica Lagascea decipiens/Leptochloa dubia TABLE 36 Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association

No. Times Species Associa­ Associa' Occurred tion* tion** Together Species 1 Species 2 1 2 35 Artemisia ludoviciana Bouteloua curtipendula .637 .350 24 Bouteloua curtipendula Gutierrezia lucida .240 .706 24 Haplopappus laricifolius Bouteloua curtipendula .533 .240 22 Bouteloua curtipendula Calliandra humilis .220 .512 19 Bouteloua curtipendula Cheilanthes Lindheimeri .190 .594 19 Bouteloua curtipendula Dalea formosa .190 .326 19 Haplopappus laricifolius Selaginella rupincola .422 .731 13 Bouteloua curtipendula Selaginella rupincola • .130 .692 17 Bouteloua curtipendula Agave Palmeri .170 .703 17 Bouteloua curtipendula Agave Schottii .170 .536 16 Dalea formosa Gutierrezia lucida .696 .471 ^Association 1 is association index of species 1 occurring with species 2. ^Association 2 is association index of species 2 occurring with species 1. TABLE 36—Continued, Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion* tion** Together Species 1 Species 2 1 2 15 Haplopappus laricifolius Agave Schottii .333 .517 14 Bouteloua curtipendula Pellaea limitanea .140 .560 14 Calliandra humilis Porophyllum gracile .326 .533 11 Bouteloua curtipendula Bouteloua filiformis .110 .579 11 Bouteloua curtipendula Dodonaea viscosa .110 .500 10 Artemisia ludoviciana Jacobinia ovata .196 .714 10 Bouteloua curtipendula Fouquieria splendens .100 .526 • 10 Calliandra humilis Haplopappus spinulosus .233 .667 10 Cercidium microphyllum Porophyllum gracile .333 .335 10 Eragrostis intermedia Agave Schottii .556 .345 10 Haplopappus laricifolius Eragrostis intermedia .222 .556 10 Haplopappus laricifolius Fouquieria splendens .222 .526 10 Porophyllum gracile Viguiera deltoidea .335 .533 9 Aristida ternipes Agave Schottii .600 .310 Echinocereus fasciculatus 9 Bouteloua curtipendula var. Boyce-Thompsonii .090 1 .529 TABLE 36—Continued. Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion* tion** Together Species 1 Species 2 1 2 9 Cheilanthes Lindheimeri Eragrostis intermedia .231 .500 9 Haplopappus laricifolius Aristida ternipes .200 .600 9 Haplopappus spinulosus Porophyllum gracile .600 .346 9 Heteropogon contortus Agave Schottii .750 .310 Opuncia acanthocarpa 9 Porophyllum gracile var. major .346 .500 Opuntia acanthocarpa 9 Tridens muticus var. major .209 .500 8 Aristida ternipes Bouteloua curtipendula .533 .080 o 0 t 8 Aristida. ternipes Selaginella rupincola .533 8 Bouteloua curtipendula Bouteloua hirsuta .080 .615 Bouteloua curtipendula Heteropogon contortus .080 .667 8 Erythrina flabelliformis Agave Schottii .615 .276 8 Haplopappus spinulosus Arabis perennans .533 .235 8 Haplopappus spinulosus Selaginella arizonica .533 .421 TABLE 36—-Continued. Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion* tion** Together Species 1 Species 2 1 2 7 Ayenia pusilia Calliandra humilis .5a3 .163 7 Bouteloua curtipendula Brickellia atractyloides .070 .637 7 Bouteloua curtipendula Erythrina flabelliformis .070 .53# 7 Cercidium microphyllum Ephedra fasciculata .533 .363 7 Cercidium microphyllum Euphorbia melanadenia .5S3 .226 7 Jacobinia ovata Simmondsia chinensis .500 .167 6 Artemisia ludoviciana Brickellia atractyloides .11S .545 6 Ayenia pusilia Bouteloua curtipendula .500 .060 6 Bouteloua curtipendula Leptochloa dubia .060 .667 6 Bouteloua curtipendula Lotus rigidus .060 .500 6 Bouteloua curtipendula Mammillaria microcarpa .060 .667 6 Boutelous curtipendula Salvia pinguifolia .060 .357 6 Bouteloua hirsuta Heteropogon contortus .461 .500 6 Calliandra humilis Cerdidium microphyllum .139 .500 6 Calliandra humilis Panicum arizonicum .139 .357 TABLE 36—-Continued. Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion^ tion^ Together Species 1 Soecies 2 1 2

6 Echeveria Collomae Porophyllum gracile .750 .231 6 Echeveria Collomae Viguiera deltoidea .750 .353 6 Haplopappus laricifolius Heteropogon contortus .133 .500 6 Haplopappus laricifolius Lotus rigidus .133 .500 6 Heteropogon contortus Selaginella rupincola .500 .231 6 Sphaeralcea laxa Tridens muticus .600 .139 5 Acacia Greggii Mimosa biuncifera .200 .625 5 Andropogon barbinodis Bouteloua curtipendula .556 .050 5 Bouteloua curtipendula Muhlenbergia Emersleyi .050 .714 5 Bouteloua curtipendula Panicum arizonicum .050 .714 5 Bouteloua curtipendula Pellaea Jonesii .050 .714 5 Calliandra humilis Sphaeralcea laxa .116 .500 5 Echeveria Collomae Selaginella arizonica .625 .263 5 Eriogonum Wrightii Sphaeralcea laxa .161 .500 5 Fouquieria splendens Mammillaria microcarpa .263 .556 TABLE 36—Continued* Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion* tion** Together Species 1 Species 2 1 2 5 Haplopappus laricifolius Mammillaria microcarpa .111 .556 5 Porophyllum gracile Sphaeralcea laxa .192 .500 5 Selaginella rupincola Trichachne californica .192 1.000 5 Simmondsia chinensis Sphaeralcea laxa .119 .500 4 Aristida adscensionis Dalea formosa .goo .174 4 Aristida adscensionis Panicum arizonicum .300 .571 4 Aristida Wrightii Artemisia ludoviciana .667 .073 4 Aristida Wrightii Bouteloua curtipendula .667 .040 4 Artemisia ludoviciana Canotia holacantha .073 .571 Artemisia ludoviciana Lagascea decipiens .073 1.000 4 Berberis trifoliolata Calliandra humilis .667 .093 4 Berberis trifoliolata Gutierrezia lucida .667 .lid Notholaena sinuata 4 Bouteloua curtipendula var. inteserrima .040 .300 4 Bouteloua curtipendula Opuntia versicolor .040 1.000

4 Bouteloua curtipendula Trichachne californica .040 .500 TABLE 36—Continued. Association Index of All Plants Occurring Together Four or More Times and Showing a 50 Per cent or Greater Association No. Times Species Associa- Associa- Occurred tion* tion** __ Together Species 1 Species 2 1 2

4 Carex sp. Eragrostis intermedia .667 .222 4 Dalea formosa Panicum arizonicum .174 .571 A 0 0 U 4 Echeveria• Collomae Euphorbia melanadenia .129 •4 Eriogonum fasciculatum Porophyllum gracile .667 .154 4 Galium stellatum Agave Toumeyana .143 1.000 O C 0 0 • 4 Gossypium• Thurberi Agave Schottii .13# 4 Lagascea decipiens Leptochloa dubia 1.000 .444 o c 0 0 - 4 Metastelma* arizonicum Viguiera deltoidea .235 4 Mimosa biuncifera Viguiera deltoidea .500 .235 145 When the density means of each of the species in the ninety-five associations (Table 36) was graphed for all areas and compared with other species which had a .500 or greater association, the following associations were closely cor­ related with three areas, Baboquivari Canyon, Molino Canyon, and El Capitan: Agave Schottii/Haplopappus laricifolius Aristida ternipes/Agave Schottii Eragrostis intermedia/Agave Schottii Eragrostis intermedia/Haplopappus laricifolius Erythrina flabelliformis/Agave Schottii Gossypium Thurberi/Agave Schottii Heteropogon contortus/Agave Schottii Heteropogon contortus/Bouteloua hirsuta Matronillaria microcarpa/Fouqu'ieria splendens Mammillaria microcarpa/Haplopappus laricifolius

In four of the areas Avenia pusilla/Calliandra humilis showed good graph correlation for areas and associations. Figure 2S shows one such graph for the Bouteloua hirsuta/Heteropogon contortus. Assoc Assoc Density- mean Bouteloua hirsuta/Heteropogon contortus 461 500 1.000

750-

A

500-.

250-

000 Organ Baboquivari Mo lino El San Mormon Pipe Canyon Canyon Capitan Carlos Flat Fig. 28. Relationship of density mean for two species with high association. Bouteloua hirsuta Heteropogon contortus DISCUSSION AND CONCLUSIONS

Vauquelinia has been present since the Madro-Tertiary (MacGinitie, 1953), and this study has revealed that a large number of genera known to be associated with Vauquelinia at that time are still found as associates in the study quadrats of the six areas. The following genera were present during the Madro-Tertiary and the present study: Acacia Dodonaea Arctostaphylos Ephedra Baccharis Euphorbia Brickellia Eysenhardtia Ceanothus Fouquieria Celtis Quercus Cercocarpus Rhus Condalia Yucca Crossosoma

Additional genera present in the Madro-Tertiary flora and which occurred outside the quadrats in the study area were: Cupressus Pinus Juniperus Prosopis

147 14S Of all the plants occurring with Vauquelinia in the Madro-Tertiary Florissant beds, Crossosoma appears to be the only one which now requires environmental conditions similar to those of the Vauquelinia californica. Most of the other genera have wider environmental adaptations and occur over extensive areas as does Prosopis and Quereus* Due to the rather limited environmental conditions under which Vauquelinia does exist and in order to obtain as much data as possible, an attempt was made to obtain a sampling of Vauquelinia growing on quadrats of different slope directions. However, more samplings of quadrats of westerly exposed slopes were obtained since it was on these exposures that the largest number of Vauquelinia plants occurred. East and south exposures were difficult to find because the geology of the areas studied tended more toward a western exposure. The density of species which occurred on the quadrats with Vauquelinia was dependent primarily upon three factors: (l) the amount of soil which had been deposited in rock depressions and cracks; (2) their ability to live upon rock (these plants must have a root system which can penetrate rock cracks and crevices); and (3) their ability to survive long periods of drought, as the Pteridophytes, for example. The number of species found growing in the study areas was large considering that the study quadrats occurred in 149 rock with little soil. Therefore, it was not unexpected that numerous Pteridophyta species were found occurring as asso­ ciates with Vauquelinia in these rocky habitats. Most of the associated plants were bushes, shrubs, and perennial herbs. In fact, few annuals survive in these habitats due to lack of soil and moisture storage. Some years have heavier than normal precipitation and more annuals survive; but, for most years and over long periods of time, a strong root system is needed to absorb water from the deep rock reservoirs. Table 37 lists the less xeric study areas and several species which occur. These species are of special interest, since with the exception of Aristida adscensionis, Krameria parvifolia, Leptochloa dubia, and Panicum arizonicum, they were the only ones found growing in only the Baboquivari, Molino, and El Capitan areas. These species appear to have a number of similar environmental requirements. Soil of the El Capitan area is of limestone origin and is finer in texture than that found in the Molino and Baboquivari Canyon areas. The latter have coarse granite soils. The El Capitan area is the only one open to domestic livestock. Two annual grasses, Aristida adscensionis and Panicum arizonicum, occurred in the area in abundance. Plants which occurred in the Baboquivari and Molino Canyon areas in­ cluded Eragrostis intermedia, Krameria parvifolia, Leptochloa dubia, and Lycurus phleoides. These species were not found in the El Capitan area, due perhaps to grazing pressure. TABLE 37 Baboquivari, Molino, and El Capitan Canyon Area Species of Special Interest

Baboquivari Molino Species Canyon Canyon El Capitan

Aristida adscensionis A A P Bouteloua filiformis P P P Bouteloua hirsuta P P P Eragrostis intermedia P P A Erythrina flabelliformis P P A Gossypium Thurberi P P A Haplopappus laricifolius P P A Heteropogon contortus P P P Krameria parvifolia P P A Leptochloa dubia P P A Lycurus phleoides P P A Mammillaria microcarpa P P P Muhlenbergia Emersleyi P P P Panicum arizonicum A A P Note: A = absent; P = present 151 Gutierrezia lucida. an increaser imder grazing pressure, occurred in greater abundance in the El Capitan area. Bouteloua curtipendula had its highest density mean in the El Capitan area which is subject to grazing. This was unexpected because Bouteloua curtipendula is a decreaser under grazing. A plausible explanation may lie in the fact that the area has a finer, deeper, limestone soil which stores more moisture than is the case in the other areas. The numerous cracks and crevices of limestone in the El Capitan area appear to provide a favorable habitat for Dalea formosa which reached its highest density in this area. No study was made of the Dalea plants other than noting that certain areas outside the study quadrats were almost com­ pletely covered by them. Two species, Viguiera deltoides and Eriogonum fas- ciculatum, occurred in only the most xeric areas, Organ Pipe and Mormon Flat. Ephedra fasciculata occurred in only the three most xeric areas, Organ Pipe, Mormon Flat, and .San Carlos. Androoogon barbinodis, Aristida hamulosa, Aristida Parishii, Lycurus phleoides. and Yucca baccata occurred more often in the southerly, SE and SW, quadrants. No explanation can be advanced other than that the plants may require more direct sunlight than would be found in the northerly quadrants. 152 Lagascea decipiens. Mimosa biuncifera. Rivina humilis. and Tridens muticus occurred more often in the northerly, NE and NW, quadrants. No explanation is known other than that the plants may require less direct sunlight. Vauquelinia plants may or may not flower each year. There is some evidence that some plants may never flower but the data are inconclusive. Moreover, the ability of the Vauquelinia to flower depends evidently not only upon environ­ mental factors alone but also upon its physiological condition. Some plants in a population flower in a given year while others in the same vicinity do not. Efflorescence occurs in Arizona from May until August. The complete flowering of a plant does not necessarily take place at one time. A portion of the plant may have seed capsules 30 per cent mature, while another portion may just be beginning to flower. However, the later inflorescences are always smaller than the earlier ones. Under adverse environmental conditions, the flowers may die in bud and never open. This latter phenomenon has been observed most frequently in the Organ Pipe area. Approximately four to five months are required from floral initiation to seed ripening. Few Vauquelinia plants had only one stem and few had more than ten. Most plants averaged from four to six stems per plant. Greenhouse-grown Vauquelinia plants showed a main stem apical dominance for approximately twelve months after 153 which the dominance weakened. When environmental stress, for example, lack of moisture, was induced the leaves of the greenhouse plants dried and dropped. Upon application of water, the axillary buds formed new leaves. However, when the plants were subjected to prolonged moisture stress, they died back to the base and upon application of water formed buds and started new growth. Lack of moisture and damage from fire are probably the chief environmental stresses which cause Vauquelinia to sprout several stems, although damage to the meristematic tissue resulting from environmental, biological, and physio­ logical causes is not ruled out. The many-stemmed plants in the Mormon Flat area are probably the result of moisture stress as this area does not have the number of cracks and crevices or drainage from rocks that the other areas have. The many-stemmed plants in the Baboquivari and Molino Canyon areas are probably the result of fire stress. Vauquelinia stem tissue has growth rings which are assumed to be annual rings. These rings were found to be only a few microns in width and necessitated the use of a microscope for counting. One stem, 13-1/2 cm in radius, had approximately 280 groxvth rings. • Thus, some of the larger plants could be several hundred years old. Vauquelinia californica grows on steep slopes. The average slope for all areas studied was 25*0 per cent. 154 Vauquelinia was never found growing on level ground. Quadrat 10 in the Baboquivari Canyon area was the most level of those studied. It had a 9 per cent slope and more soil and grass species than any of the others. Vauquelinia may occur on vertical cliffs. The steepest quadrat studied had a 74*2 per cent slope. This quadrat was in the San Carlos area and as steep as practicable for purposes of sampling. The flattest area in which the entire genus Vauquelinia was found growing was in the Guadalupe Canyon area of southeastern Arizona, and near Oaxaca, Oaxaca, Mexico. The Vauquelinia occurred on similar type limestone in both areas. It was observed that, without exception, all Vau­ quelinia plants grew from rock cracks. Vauquelinia was found on sedimentary, igneous, and metamorphic rock. The important ecological consideration is not the kind of rock but that it be rock having crevices or cracks for storage of water. One ecological characteristic in particular which enables Vauquelinia to survive in its harsh environment is its root system. Vauquelinia roots have tremendous force and underground reservoirs of water are often reached by penetrating rock cracks. The author has never seen a Vau­ quelinia plant in the field which showed visible signs of moisture stress. However, moisture stress in Vauquelinia californica can be readily induced, observed and studied in greenhouse plants. Preliminary observations indicate that 155 Vauouelinia may require more moisture than other species occurring with it. However, Vauouelinia, with its deep penetrating root system, has access to a plentiful supply of water. Based on field observations, mature Vauouelinia plants do not compete with other plants in the same area. The only point at which competition, may enter is during seed germination and during the plantfs establishment. Once the Vauouelinia plant is established, the roots have the ability to follow or enlarge existing cracks which lead to underground water reservoirs. Very few long-lived perennial plants grow in close proximity to mature Vauouelinia plants. Plants that occur with Vauouelinia have a much shallower root system and, sub­ sequently, take advantage of the small amount of soil that is available. Only one Vauouelinia californica plant showing signs of being browsed was observed in the study areas. However, numerous Vauouelinia pauciflora plants are- browsed in the Guadalupe Canyon area of Cochise County, Arizona. Some Vauouelinia californica plants showed evidence of insect foraging, although to no great extent. A Vauouelinia in the Superstition Mountains was observed to have been parasitized by Phoradendron californicum. Over thousands of years, Vauouelinia seed have fallen into cracks and crevices and germinated. If the cracks 156 extended to subsurface water, the plant survived. The author believes that Vauquelinia occupies all suitable openings of cracks and crevices in the vicinities studied. There are few small Vauquelinia californica and those that are, probably remain so until rock fracturing occurs or until some means makes subsurface water available. Figure 29 shows how usable rainfall is increased in volume in those areas where it falls on rock. After falling it runs down to lower rock formation levels. It continues on its downward path until it reaches a crack leading to an underground reservoir where it is stored or from which it eventually seeps out. This water is available to Vauquelinia. This is apparent as shown by the Vauquelinia growing on rocky, barren areas (Fig. 29)• There is a sharp line of demarcation appearing below the Vauquelinia where the soil begins to deepen. Here, as shown in Figure 29 foreground, more moisture can be stored close to the surface where it is more readily available to grasses, herbs, and shrubs-. The species listed in the Dice Index (Table 36) are associated with one another because of the presence in their habitat of certain features attractive or essential to survival. There appears to be no other relationship between them other than that they require the same environmental con­ ditions. However, it is unknown whether any one species is mutually attracted to or dependent upon another, but there are indications that Bouteloua hirsuta and Heteropogon + &Z' . ~ > " "V •58&.lJ&:

Fig. 29• Upper study in Baboquivari Canyon area. H vn 15# contortus might be mutually attracted although not dependent. The fact that some species may have an adverse affect on other species has not been ruled out. Several species were located within the study area which were not recorded in any sample quadrat. All that can be ascertained is that certain species (Table 36) occur together more frequently than others. There are, however, plants in the study areas that did not occur together in quadrants close to Vauquelinia. A number of species with an association index of 1.0 can be accounted for solely by their having occurred only once or twice jointly. The Dice Index did, however, tend to separate the xeric from the less xeric species and, in some instances, plants were grouped according to the same type of habitat. Table 33 lists six taxa which were found in the study areas. The listing is a good indicator of environmental conditions in the study areas, and shows that the more xeric areas have fewer species than the less xeric. The large number of Gramineae and Leguminosae in the Baboquivari, Molino, and El Capitan areas indicates a less xeric condition than the other areas. Absence of Polypodiaceae in the Mormon Flat area is indicative of few cliffs and rocks under or around which the Polypodiaceae grow. A number of high association index percentages was obtained for several plants with a high density in one area, but only because the comparison species had a high density TABLE 33

Species of Six Taxa Found in Study Areas

Baboquivari Molino Mormon Organ Pipe Canyon Canyon El Capitan San Carlos Flat Taxa (No.) (No.) (No.) (No.) (No.) (No.) Gramineae 7 14 12 17 6 3 Leguminosae 2 7 7 ' 7 2 4 Cactaceae 1 3 5 4 4 4 Amaryllidaceae (Agave) 2 1 2 2 2 0 Polypodiaceae 8 5 7 5 3 1 Compositae 3 4 3 7 3 6

Total 23 34 36 42 20 23 160 in several areas. There were few plants with approximately the same density in any of the areas (Table 10). Vauquelinia californica in southern Arizona has a wider ecological adaptation than some of the species associated with it. It occurs with Ephedra fasciculata and Cercidium microphyllum at the lower xeric areas. Vauquelinia also occurs in higher less xeric areas where Pinus cembroides and Juniperus deppeana are found. Some species occur with Vauquelinia in only one area and others, like Bouteloua curtipendula, occur in all or several of the areas. The percentage of plants with highest density mean in each given area is recorded in Table 39. Baboquivari Canyon has the highest percentage, 59#6; and Organ Pipe, the lowest, 31.7. This would appear to suggest that the Baboquivari Canyon area is more stable; that is, there are less climatic fluctuations and more ecological niches, which are not con­ stantly changing due to adverse environmental conditions, such as drought. Thus, this areafs environment is not so harsh as that of the Organ Pipe and more plants have.managed to survive. In the Organ Pipe area, 31.7 per cent, that is, only half as many plants reached their peak occurrence as compared to the 59.6 per cent in the Baboquivari Canyon area. On this basis, it would appear that some species in the Organ Pipe area may be dying out or that new species are coming in. However, this study presents indications that the Organ Pipe area may be in unstable equilibrium. The El Capitan area had TABLE 39 Percentages of Species with Highest Density Mean in Study Areas

Species with Highest Mean Total Species % with Area (No.) (No.) Highest Mean

El Capitan 37 67 55.3 Baboquivari Canyon 33 57 59.6 Molino Canyon 29 49 59.1 Mormon Flat 22 44 50.0 Organ Pipe 13 41 31.7 San Carlos 11 34 32.3 162 a lower percentage of total species than did the Baboquivari and Molino Canyon areas. The explanation may be that grazing pressure lowered the mean density of the species in the area. Herbarium specimens obtained from different institu­ tions and the authorTs own personal collections verified the field and laboratory analysis of variability within and be­ tween different study areas.. Specimens showed the Organ Pipe Vauquelinia leaves to be longer, narrower, with more pubes­ cence and to have larger but fewer spines than those of the other areas. Plants from the Gila and Salt River area showed leaves to be wider, almost glabrous and having many small spines. Vauquelinia californica leaves, as had been demon­ strated by field stud}*-, laboratory analysis, and greenhouse experiment, were variable as to length, width, petiole length, and number of spines. Although individual characteristics of the plants were variable, each area had a genetic unity. The latter observation was substantiated by morphological char­ acters which had been studied. Greenhouse-groivn plants demon­ strated the variability between and within different areas. These plants also showed the genetic unity that occurred in each area. Leaves of Vauquelinia californica occur in a loose or compacted terminal cluster from 10 to 30 cm in length and normally remain upon the plant for two years. Leaf edges 163 vary in morphological character. Some are almost entire while others are double-serrate. By comparison, some leaves in the Organ Pipe area were noted to be slightly revolute, the San Carlos leaves were almost flat, and the Baboquivari area leaves had a tendency to be undulate. Variability in leaf data among all the quadrants was only slight. Correlation data showed that petiole length was highly correlated with leaf length and width and that leaf spine number was highly correlated with leaf width. Larger leaf veins were terminated by spines. The narrower the leaf the less the veins branched and, therefore, the fewer spines were larger. An analysis of all seed data showed that seeds in Organ Pipe differed from those of all other areas in that each of the four measured variables was larger. Climatic conditions may be unsuitable for germination of Vauquelinia seed in most years in the- xeric Organ Pipe area. As a result, selection may have been for larger seed's which might remain viable for a longer period of time. The larger seeds may contain more of various physiological substances necessary for long-term viability. Preliminary analyses, based on germination tests in the summer of 1970, of seed collected in 1965 showed that the Organ Pipe area seed had the highest percentage of germination, lending further evidence to this hypothesis. Correlation data for seed showred that seed length and wing length were highly correlated and that seed width and 164 seed length were not so highly correlated. It would appear from this analysis that natural selection has placed emphasis on maintaining a certain ratio of wing length to seed length and wing width to seed width. The author believes that the primary difference in morphology of Vauquelinia californica in the different areas is the result of genetic isolation. The different mountain ranges have been separated by desert floor for long periods of time, and the different populations have not exchanged genetic material. The different study areas have different environ­ mental conditions now, and such was also the case in the past. These different environmental conditions of both the past and present are recorded in the living plant species. Organ Pipe and Mormon Flat areas were found to be more xeric than the other areas. In fact, Vauquelinia plants from each area were very dissimilar from those of the other area. The Organ Pipe area plants had narrow leaves and, therefore, minimum surface area. Furthermore, the leaves had a thick pubescence on the lower surface. The Mormon Flat area plants, on the other hand, had wide leaves and scarcely any pubescence. The selective factor or factors ivhich caused this morphological variability is unknown. However, it could be the result of genetic isolation. The author proposes that the San Carlos area Vauquelinia is the Vauquelinia from which Major Emory made his collection, 165 a collection which was of the type species of Vauquelinia californica. This is verified by comparing the leaf in Figure 30 with those in Figures 24 and 27• The study was not designed to statistically separate Vauquelinia populations into new groupings. However, some important taxonomic differences were observed among the study areas. These differences were noted for leaf length, leaf width, and number of spines per cm of linear length for leaf margins which suggested that populations of Vauquelinia in Molino and Baboquivari Canyon areas could be a sub-species. Seed measurements from the study areas also substantiate this population division. Leaf and seed characteristics further indicate that sufficient evidence may be present to separate the Organ Pipe population into a new species of Vauquelinia. Further study using appropriate statistical procedures may also be helpful in separation of the Organ Pipe population into a new species. Fig. 30• Enlargement of Vauquelinia californica leaf collected by Major Emory (lower right portion, Fig. 2). APPENDIX A

PTERIDOPHYTA FOUND ON AT LEAST ONE STUDY PLOT

The Pteridophytes consisted of two families: the Selaginellaceae and Polypodiaceae. The species are listed as follows: PTERIDOPHYTA (see: Kearney, Peebles, and Collaborators, I960) Selaginellaceae Selaginella arizonica Selaginella rupincola

Polypodiaceae Bommeria hisoida Cheilanthes Lindheimeri Cheilanthes tomentosa Notholaena aurea Notholaena sinuata Notholaena sinuata var. integerrima Pellaea Jonesii Pellaea limitanea Pellaea longimucronata

167 APPENDIX B

SPERMATOPHYTA FOUND ON AT LEAST ONE STUDY PLOT

The Spermatophytes consisted of one Gymnospermae and numerous Angiospermae of both Monocotyledons and Dicotyledons, and are listed as follows: . SPERMATOPHYTA (see: Kearney, Peebles, and Collaborators, I960)

Gymnospermae Ephedraceae Ephedra fasciculata

Angiospermae Monocotyledoneae

Amarvllidaceae Agave deserti Agave Palmeri Agave Schottii Agave Toumevana

Commelinaceae Commelina erecta

16S Commelina ereeta var. crispa

Cyperaceae Carex sp.

Gramineae Festucoideae: Aristida adscensionis Aristida barbata Aristida Fendleriana Aristida hamulosa Aristida pansa Aristida Parishii Aristida ternipes Aristida Wrightii Bouteloua curtipendula Bouteloua filiformis Bouteloua hirsuta Eragrostis intermedia Hilaria Belangeri Leptochloa dubia Lvcurus phleoides Muhleribergia Emerslevi Muhlenbergia monticola Muhlenbergia Porteri Stipa comata Stipa neomexicana Stipa speciosa Tridens muticus

Panicoideae; Andropogon barbiriodis Elyonurus barbiculmis Heteropogon contortus Panicum arizonicum Panicum capillare Panicum Hallii Setaria macrostachya Trichachne californica

Liliaceae Dasylirion Wheeleri Nolina microcarpa Yucca arizonica Yucca baccata

Dicotyledoneae

Acanthaceae Anisacanthus Thurberi Jacobinia ovata

Anacardiaceae Rhus trilobata Asclepiadaceae Asclepias angustifolia Metastelma arizonicum

Berberidaceae Berberis trifoliolata

Buxaceae Simmondsia chinensis

Cactaceae (see: Benson, 1969) Cereus giganteus Echinocereus fasciculatus var. Boyce-Thompsonii Ferocactus acanthodes var. LeContei Ferocactus Wislizenii Mammillaria microcarpa Opuntia acanthocarpa var. major Opuntia phaeacantha var. discata Opuntia phaeacantha var. laevis Opuntia phaeacantha var. roa.ior Opuntia versicolor Opuntia violacea var. santa-rita

Celastraceae Canotia holacantha

Compositae Artemisia ludoviciana Baccharis glutinosa Brickellia atractvloides Chrvsopsis hispida Encelia farinosa Eupatorium pauperculum Gutierrezia lucida Haplopappus laricifolius Haplopappus spinulosus Lagascea decipiens Melampodium leucanthum Porophvllum gracile Psilostrophe Cooperi Trixis californica Viguiera deltoidea Zinnia pumila

Convolvulaceae Evolvulus pilosus

Crassulaceae Echeveria Colloinae

Crossosomataceae Crossosoma Bigelovii

Cruciferae Arabis perennans Draba cuneifolia Halimolobos diffusus Ericaceae Arctostaphvlos pungens

Euphorbiaceae Euphorbia arizonica Euphorbia melanadenia Jatropha cardiophvlla Tragia nepetaefolia

Fagaceae Quercus oblongifolia Quereus reticulata Quercus turbinella

Fouquieriaceae Fouquieria splendens

Labiatae Salvia pinguifolia

Leguminosae Mimosoideae: Acacia constricta Acacia Greggii Calliandra humilis Mimosa biuncifera Caesalpinioideae: Cassia Covesli Cercidium microphvllum Krameria Gravi Krameria parvifolia

Papilionoideae: Dalea formosa Erythrina flabelliformis Eysenhardtia -polystachya Galactia Wrightii Lotus rigidus Nissolia Schottii Rhynchosia texana

Malpighiaceae Janusia gracilis

Malvaceae Abutilon parvulum Gossypium Thurberi Hibiscus Coulteri Malvastrum bicuspidatum Sphaeralcea Fendleri Sphaeralcea laxa

Oleaceae Menodora scabra Oxalidaceae Oxalis stricta

Phytolaccaceae Rivina humilis

Polygonaceae Eriogonum fasciculatum Eriogonum Wrightii

Rhamnaceae Ceanothus Greggii Condalia lycioides

Rosaceae Cercocarpus montanus

Rubiaceae Bouvardia glaberrima Galium microphyllum Galium stellatum

Sapindaceae Dodonaea viscosa

Scrophulariaceae Penstemon pseudospectabilis

Solanaceae Lycium Berlandieri Sterculiaceae. Ayenia pusilia

Ulmaceae Celtis pallida

Verbenaceae Aloysia Wrightii

Zygophyllaceae Tribulus terrestris REFERENCES

Axelrod, Daniel I. Evolution of the Madro-Tertiary Geoflora. Botanical Review, 24: 433-509, 1958. Benson, Lyman. The Cacti of Arizona. Arizona: University of Arizona Press, 1969•

Benson, Lyman and Darrow, Robert A. A Manual of Southwestern Desert Trees and Shrubs. Biological Science Bulletin, University of Arizona, 1944. Brown, R. W. Recognizable Species of the Green River Flora. U. S. Geologic Survey, Professional Paper 185: 45-77, 1934. Cain, S. The Species—Area Curve. American Midland Natu­ ralist , 19: 573-5^1, 1938. Dice, L. R. Measures of the Amount of Ecologic Association between Species. Ecology, 26: 297-302, 1945- Emory, William H. Report on the United States and Mexican Boundary Survey. Washington: Cornelius Wendell, printer, 1859* Greene, Christine R. and Sellers, William D. (eds.). Arizona Climate. Arizona: University of Arizona Press, 1964. Humboldt, Alexander, Freiherr von, and Bonpland, Aime Jacques Alexandre. Plantes Equinoxiales. Vol. 1: 140 t, 40, 1808-1809. Interior-Geological Survey, Arizona. Washington, D. C.: 1957—NS, M-R 3680. Kearney, Thomas H„ Peebles, Robert H., and Collaborators. Arizona Flora. 2d ed. Berkeley: University of California Press, I960. MacGinitie, H. D. Fossil Plants of the Florissant Beds, Colorado. Carnegie Institute Washington, Publica­ tion No. 599: 1-188, 1953.

177 17# Sargent, C. S. Garden and Forest, August 21, lS$9, P» 400. Shreve, Forrest and Wiggins, Ira L. Vegetation and Flora of the Sonoran Desert. California: Stanford University Press, 1964. Smith, H. V. The Climate of Arizona. Agricultural Experiment Station Bulletin, University of Arizona Press, No. 279, September, 1956. Steel, Robert G. D. and Torrie, James H. Principles and Pro­ cedures of Statistics. New York: McGraw-Hill Book Company, Inc., I960. Torrey, John. Emory's Rep., 140, Ex. Doc. No. 41, 1&4&» Watson, Sereno. Botanical Contributions. 3* Descriptions of new species of plants, chiefly Californian, with revisions of certain genera. Proceedings of.the American Academy of Arts and Sciences, XI, 147, 1$76.