Vegetation and Flora of the San Bernardino Ranch

Home , Aristolochia watsonii, Calycoseris wrightii, Hilaria mutica, Portulaca suffrutescens, San Bernardino Ranch, Sporobolus airoides

VEGETATION AND FLORA

OF THE SAN BERNARDINO RANCH,

COCHISE COUNTY, ARIZONA

Gayle Ellen Marrs—Smith

A Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science

ARIZONA STATE UNIVERSITY

December 1983 VEGETATION AND FLORA

OF THE SAN BERNARDINO RANCH,

COCHISE COUNTY, ARIZONA

Gayle Marrs-Smith

has been approved

July 1983

APPROVED:

,Chairperson

Supervisory Committee

ACCEPTED:

Departmental Chairpers9:ri

0E444,,, 7/7, 4,6 Dean, Graduate College ABSTRACT

The San Bernardino Ranch, recently purchased by the U.S. Fish and Wildlife Service, lies within the San Bernardino Valley in extreme southeastern Cochise County, Arizona. It is bordered on the north, east, and west by private and public ranchland, and on the south by

Mexico. The vegetation is primarily Chihuahuan Desert Scrub and Desert

Grassland. A unique feature of the San Bernardino Ranch is the occurrence of freshwater marshes or cienegas which are supported by numerous active artesian wells and springs. Eight natural plant communities have been recognized in the study area: Chihuahuan Desert Scrub, Desert

Grassland, Mesquite Bosque, Riparian Forest/Woodland, Riparian Scrub,

Marshland, Aquatic, and Old Field/Disturbed.

The known native and naturalized vascular flora of the San Bernar- dino Ranch and immediate vicinity consists of 343 taxa including 340 species in 230 genera from 72 families. Two taxa previously questioned as occurring in Arizona were collected during the course of the study: lbervillea tenuisecta (Gray) Small (Cucurbitaceae) and Corchorus orinocensis H.B.K. (Tiliaceae). DEDICATION

In memory of Ruth I. Marrs, my mother and friend, who spawned my interest in plants by her own awareness of the plant kingdom's astonishing beauty.

i v ACKNOWLEDGEMENTS

I wish to express my sincerest gratitude to the following indiv-

i duals who greatly assisted me during the course of this thesis.

Dr. Donald J. Pinkava guided me throughout the project, assisted in the identification of certain plant taxa, and provided helpful suggestions in the manuscript. Gerry Burton and Jim Johnson both of the U.S. Fish and Wildlife Service suggested the idea of doing a flora of the SB Ranch and were helpful throughout the study. The staff of

The Nature Conservancy in Tucson were of great assistance: Terry John- son negotiated access to and lodging at the SB Ranch; Tom Van Devender sent me some specimens he collected while he was there and gave me access to his more interesting plant data of the area; and Larry Toolin kindly permitted me access to all his collection data of the study area.

The other members of my committee are gratefully acknowledged:

Dr. W.L. Minckley provided some financial support and with Dr. Duncan

T. Patten critically reviewed the manuscript. Those who kindly aided i n the collecting of plants and sampling of vegetation were Dave Bowman,

Thomas Clark, Thomas Daniel, Phil Johnston, and Sandra Limerick. My special thanks to Rusty Kologiski, Dirk Lanning, and Stan Smith, who generously gave their time and expertise in the community analysis of vegetation. Dirk also permitted me to use his vegetation map of the study area. Mrs. Helen Ramsower supplied specific historical information about the study area. Dr. Stuart G. Fisher and Nancy Grimm provided laboratory facilities for water chemistry analyses. The following kindly assisted in the identification of some plant groups: Dr. David Keil, Compositae; Bruce Parfitt, Lemnaceae; Dr.

Donald J. Pinkava, Cactaceae, lbervillea (Cucurbitaceae); Mark Molhen- brock, Coryphantha (Cactaceae). Their aid is deeply appreciated, however I assume full responsibility for all taxa cited in this report.

Lastly I am indebted to my parents, Robert L. and the late Ruth

I. Marrs, and my husband, Stan Smith, all who gave me their full support, assistance, and encouragement.

vi ,

TABLE OF CONTENTS

Page

LIST OF TABLES ... viii

LIST OF FIGURES i x

INTRODUCTION ...... 1

HISTORY 2

HISTORY OF BOTANICAL COLLECTIONS ...... 6

GEOGRAPHY, TOPOGRAPHY, AND SURFACE HYDROLOGY ...... 9

Geography ...... 9

Topography ...... 14

Surface Hydrology .....1 4

CLIMATE ...... 19

GEOLOGY ...... 23

HYDROLOGY ...... 25

VEGETATION .....28

Classification and Successional Trends ..... 29

Vegetation Analysis ..... 29

Major Communities ..... 35

RECOMMENDATIONS FOR PROTECTION OF THE SB RANCH ..... 48

CATALOGUE OF VASCULAR PLANTS ..... 48

LITERATURE CITED ..... 91

ADDENDUM ..... 95 LIST OF TABLES

Page Table

-1 1 Summary of water chemistry (each parameter as mg 1 ) and water temperature (°C) from the artesian sources (8 sample locations) and Black Draw (2 sample locations) at the San Bernardino Ranch, taken by the author in 1981. Data are presented as mean ± 1 S.D. for sample sizes of 8 (artesian) and 2 (Black Draw); replicate samples were not taken for cations 26

2 Vegetational communities of the San Bernardino Ranch (after Lanning, 1 981) 30

3 Desert Grassland transect data ...... 37

4 Chihuahuan Desert Scrub transect data ...... 39

5 Mesquite Bosque transect data ...... 42

6 Marshland transect data ...... 45

7 Taxonomic composition by major categories of the flora of the San Bernardino Ranch ...... 50

8 Taxonomic composition by the ten l argest families represented at the San Bernardino Ranch ...... 51

viii LIST OF FIGURES

Page Figure

1 Map of southeastern Arizona, showing the l ocation of the San Bernardino Ranch ...... 1 0

2 Drainage pattern of the San Bernardino Valley 1 2

3 General topographical features of the San Bernar- dino Ranch ...... 15

4 Climatological data ...... 20

5 Vegetational communities for the western half of the San Bernardino Ranch ...... 31

6 Vegetational communities for the eastern half of the San Bernardino Ranch ...... 33

i x INTRODUCTION

The San Bernardino Ranch in southeastern Cochise County, Arizona, was purchased in 1982 by the United States Fish and Wildlife Service

( USFWS) because of the presence of populations of endemic endangered fishes (Hendrickson et al., 1980). The purpose of my study was to obtain baseline information of plant species composition and vegetation types to ascertain habitat composition, which will aid in determining future changes and their effect on the maintenance of taxa and habitat.

Because the San Bernardino Ranch has been moderately to heavily grazed by domestic livestock for many years, this type of information should be particularly useful in providing an initial appraisal of vegetation of the area prior to anticipated succession upon removal of grazing pressure. Prior to this study vegetation types in the San Bernardino

Ranch area were mapped by Lanning (1981). Sixty-five species were documented as occurring in a preliminary survey of vascular plants by

Larry Toolin (unpubl.) of The Nature Conservancy in 1980. HISTORY

History of the San Bernardino Ranch, hereafter referred to as

SB Ranch, is long, colorful, and reasonably well documented. Because of the numerous permanent springs, which occur in an otherwise arid l andscape, the SB Ranch has been a focal point of human activity.

Three periods of history are discussed below: pre-history, exploration, and permanent settlement.

Pre-history: Cochise County Parks Advisory Commission (CCPAC)

(1980) best summarizes pre-history of the SB Ranch until appearance of Spanish Jesuits in the early 1700's. Little is known of Indians thought to have inhabited this area, although speculation is that several different cultures occupied it over time. Artifacts such as mortars, pestles, metates, and other tools have been discovered at various sites, which indicate that these ancient peoples led an agrar- i an existence. Their villages appear to have centered around the artesian springs; for example, an Opata Indian village still existed near springs in the vicinity when the first white men entered the area in the early 18th century. According to Sauer (1930), it is likely these peaceful Indians were driven from the area in the mid-1700's by the semi-nomadic Chiricahua Apaches.

Exploration: occupation of the area by Spanish Jesuits in the early 1720's initiated an exploration period (Gregor, 1958; CCPAC,

1 980). First recorded history of the SB Ranch is in Jesuit documents, which mention San Bernardino by name and location. They built resting sites, but nothing permanent appears to have been constructed. Because of frequent attacks from hostile Apache Indians, who resided in the Chiricahua Mountains to the north, detachments of Spanish soldiers from neighboring presidios were stationed on the flat-topped hill l ater named Mesa de la Avanzada (Mesa of the Advanced Guard). The constant threat of Indian attacks made settlement virtually impossible and attempts to establish a presidio in 1775 failed. In 1820, an at- tempt was made by Ignacio de Perez to establish a buffer state against the Apaches. He received title to the 29,640 ha (73,240 acres) San

Bernardino Land Grant. Perez stocked the land with livestock and ranched for about 10 years before attrition from Apache raids forced him to abandon both ranch and livestock. Between the mid-1840's and early 1880's, the surviving cattle together with the springs made the SB Ranch a desirable stopping site for numerous military campaigns, i mmigrant trains, and explorers passing through what is now southern

Arizona and northern Sonora. The southern route to California, which passed through the SB Ranch, was established by Philip St. George

Cooke and his Mormon Battalion in 1846 (Cooke, 1848). Other travelers such as many of the "forty-niners" used this trail and mentioned SB

Ranch in their accounts (Aldrich, 1851; Powell, 1931). Explorers also stopped at SB Ranch (Froebel, 1859; Box, 1869). After the

Gadsden Purchase of 1853, United States Boundary Surveys met at the SB

Ranch to establish the border between the United States and Mexico

(Bartlett, 1854; Emory, 1857). Establishment of the new boundary placed most of the original land grant in Mexico, with only about 970 ha (2,400 acres) in the United States (Wagoner, 1975). The Apache campaign of Crooke and Bourke in 1883 removed the Apache influence from southern Arizona; the San Bernardino Valley was afterward open 4

to permanent settlement (Bourke, 1886). About 10 years later, the last

Mexican Boundary Survey finalized the boundary between the United States and its southern neighbor (Mearns, 1907).

Settlement: this period began in 1884 when "Texas" John Slaughter purchased the SB Ranch on both sides of the border from descendents of Perez. The Slaughter Ranch made up about 14,000 ha (35,000 acres) north of the border, which included most flowing water of the valley

(Wagoner, 1975). Slaughter initiated many changes on the SB Ranch

(Gregor, 1958; Erwin, 1965; Wagoner, 1975).

For 40 years Slaughter devoted himself to developing one of the

l argest ranches in Arizona; he eventually accumulated over 50,000 cattle, and became one of the foremost "cattle barons" of that time.

He built a large adobe ranch house, barns, granaries, workshops, and a village for ranch employees. Waters of several adjacent artesian springs were impounded by a rock dam for recreation and irrigation purposes. Artesian wells were drilled, springs were capped or impounded, and elaborate systems of irrigation ditches were dug. Slaughter drained much of the existing marshland and planted more than 200 ha

(500 acres) in barley, wheat, beans, and cotton. Large orchards and vineyards also were maintained. In 1892 and 1893, a severe drought over the entire Southwest led to depletion of grasses which was further exacerbated by overstocking of ranges. Slaughter and other ranch- ers lost large numbers of cattle to starvation. Suffering considerable financial losses, Slaughter sold some of his land and mortgaged his ranch. Partially recovering later, he continued to ranch until his death in 1922. In 1937, the ranch was divided and roughly 1,000 ha 5

(2,471 acres) north of the International Boundary were sold to Marion

L. Williams. In the late 1960's, Williams sold the SB Ranch to Mr. and

Mrs. Paul A. Ramsower, who raised cattle and cultivated more than 100 ha (250 acres) of alfalfa and various grasses (pers. comm., 1981).

In 1979, The Nature Conservancy acquired the SB Ranch, serving as a temporary trustee until it was permanently transferred to the USFWS i n spring 1982. Not included in this transfer were several acres that i ncluded historical buildings such as the Slaughter ranch house, workshops, barns, etc., which were passed to Johnson Historical Museum of the Southwest. Under the USFWS, the SB Ranch is included as a part of the national wildlife refuge system; management plans have been initiated to reestablish and expand marshlands and populations of native fishes. HISTORY OF BOTANICAL COLLECTIONS

Contributions to botanical knowledge of the SB Ranch began in the mid-19th century with descriptions in journals of passing travelers.

While interesting, these accounts are mostly too general to be of great botanical use, although frequent reference to lushness of stream and marsh habitats suggests that wetlands were then more extensive.

In 1 846, General Cooke (1848), l eader of the Mormon Battalion, gave a general description of vegetation of the surrounding area. Several years later, H.M.T. Powell (1931), a "forty-niner" enroute to California via the SB Ranch, complained of swampy conditions of his campsite and of swamp grass grazed there by his cattle. John Bartlett (1854) of the first Mexican Boundary Survey (1850-1853) described the San Bernardino

Valley as a "luxuriant meadow". In 1 853, surveyer William H. Emory

(1857) also noted numerous springs, rushy ponds, and thick grasses occurring in the area. It was this survey that provided some detailed botanical information. Six botanists— C.C. Parry, G. Thurber, C.

Wright, J.M. Bigelow, E.K. Smith, and A. Schott— were assigned to the surveying crews, but only the route of Thurber has been traced (Emory,

1 857). The resulting collection data was published in John Torrey's

"Botany of the Boundary" in 1 859. Though references to localities are vague, all the botanists apparently collected in Guadalupe Canyon and

Pass (east of the SB Ranch) and at Santa Cruz in north-central Sonora.

A few references were made to the San Bernardino Valley, but precise localities are lacking. In 1 854, two independent explorers, Julius Froebel and Michael Box, stopped at the SB Ranch during travels through northern

Sonora, both attesting to its lush wetland vegetation (Froebel, 1859; 7

Box, 1869). In memoirs of his 1883 Indian campaign, William Bourke

(1886) gave brief attention to the surrounding vegetation, and comment-

ed on the abundance of spring water that issued from the ground on the

International Boundary at the SB Ranch.

Probably the most important botanical inquiry was made during the

final Mexican Boundary Survey in 1892, chiefly through efforts of

mammalogist E.A. Mearns. His study area was confined to the immediate

vicinity of the boundary, and he incorporated valuable descriptions and

lists of plants found at his collecting stations, all bearing precise collection localities in his "Mammals of the Mexican Boundary of the

United States". Mearn (1907) wrote:

"The San Bernarino River...is wooded with willow, cottonwood, boxelder, ash and mesquite; a few red junipers grow on adjacent hills; and creosote bush, mesquite, acacia and ocotillo occupy the stony mesas and arroyos which constitute the major portion of that region. The broad meadows below the San Bernardino Springs are now covered by grazing herds; but at the time of Emory's survey they were occupied by a dense growth of cane which has since entirely disappeared. Waterfowl were abundant along the San Ber- nardino River and on marshy meadows and pools below the springs."

Under private ownership, little if any botanical inquiry was under-

taken. Interest in the area as a refuge for native fishes intensified

since the 1960's (pers. comm., W.L. Minckley, 1980; Hendrickson, et al.,

1 980), but it was not until The Nature Conservancy acquired the SB

Ranch in 1979 that any significant botanical investigation was Inade.

Larry Toolin the The Nature Conservancy made collections during spring

1 980, which are deposited at University of Arizona (ARIZ). Donald J.

Pinkava and Elinor Lehto of Arizona State University collected certain

aquatic taxa during summer 1980, which are deposited at ASU. In 1981,

Dirk V. Lanning mapped vegetation of the SB Ranch while undertaking a S vertebrate inventory. Although Lanning made no collections, he provided valuable information concerning major vegetation communites

( Lanning, 1981). GEOGRAPHY, TOPOGRAPHY, AND SURFACE HYDROLOGY

Geography

The SB Ranch is in the extreme southeastern corner of Cochise

County, about 28 km (18 miles) due east of Douglas, Arizona, 31°29'N l atitude, 109°16%4 l ongitude, 1,158 m (3,800 ft) elevation. It comprises 994 ha (2,433 acres), and is immediately bounded on the east, west, and north by privately owned or leased ranchland and on the south by Sonora, Mexico (Fig. 1). The SB Ranch is in the approximate center of

San Bernardino Valley, the uppermost Rio Yaqui drainage, whose waters drain through Sonora into the Gulf of California. The International

Boundary and Water Commission (IBWC) (1979) and USFWS (1980) provide general descriptions of geography of the San Bernardino Valley. It is a long, gently-sloping basin, oriented north-south, with drainage southward from the United States into Mexico. The valley is enclosed on both east and west sides by nearly parallel mountain ranges, which i n the United States include the Paria-Pedregosa-Chiricahua ranges on the west, and the Peloncillo-Guadalupe ranges on the east. The southern boundary of the San Bernardino Valley is Arroyo Cajon Bonito in Mexico, and the northern boundary is a low ridge that separates it from the

Sulfur Springs Valley, whose waters drain northward into the Gila River.

Overall drainage pattern of the San Bernardino Valley is in Fig. 2.

Access to the SB Ranch is eastward from Douglas, Arizona, on 15th

Street, which becomes the Geronimo Trail outside of Douglas, or south and west from Animas, New Mexico, via State Highway 338 then unimproved gravel road over Guadalupe Pass. 1 0

Fig. 1. Map of southeastern Arizona, showing the location of the San Bernardino Ranch in relation to other landmarks (after Sauer, 1 930). „I ::-...,-... . • - : 1.....R,:::..... • . '.. ... ,„.., . . • 0. en • -. VA — . - - -. a : R ... KCY';':**".'; `‘ . - o..1 r 31 ' ••• .'• - • . T.I'VtE•A‘ 6 , ,44' * 4:r. ; • . . rAtA‘.s .:".• • • • , ,• •*.+11, - . .4.. *- - ..'-' •.-A....‘put't.‘ 1.Z• .c•... • - ."-.. • IV •,..-. .0.0:.• 4...... h • -.41% ,-.0 - 0 :. 4 - - -0. :. • I %. kCIN' f _o:'. .' . 1-:....- 1•::4 XS ••:',. 0:-*. ' M • . . '. ' A•it c!,*r*/-, -- ':-:- • , ..,::' gt;;V° . • -,ildc' ; y • s'',0 .-0 'R ' • : 1. • T. . I •■ • - - • 4T ' ". 12

Fig. 2. Drainage pattern of the San Bernardino Valley (International Boundary Water Commission, 1979).

114

Topography

Topographical features of the SB Ranch include a smooth alluvial flood plain with little relief other than low mesas and rolling hills that make up the uplands (Sauer, 1930). One such mesa occupies the western third of the SB Ranch, while low hills prevail throughout central and eastern areas. Gently sloping inter-mesa areas comprise low-

l ands through which streams and springs flow (Fig. 3). Elevations with-

i n the SB Ranch range from 1,183 m (3,880 ft) at the northwest corner to 1,134 m (3,720 ft) at the border (Lanning, 1981). Sauer (1930) described the valley as a partially dissected basin with deeply eroded stream beds and arroyos. Dissected areas of the SB Ranch include Black

Draw (historically the Rio San Bernardino), Hay Hollow Wash, and other smaller, unnamed arroyos on the eastern side (see Fig. 3). Cooke and

Reeves (1976) reviewed "arroyo cutting", and described processes and approximate times of recent channel trenching for the arid Southwest.

During periods of flooding, Rio San Bernardino historically overflowed

i ts banks, spreading widely over the valley floor and depositing allu-

vium in adjacent floodplains. The process of aggregation giving away to erosion of the river channel occurred sometime between 1880 and 1890.

It is not known what exactly initiated the downcutting ( Hendrickson and

Minckley, '1983).

Surface Hydrology

Before 1880 Black Draw and the adjacent springs were integrated during periods of high flow when the river water spread into spring-

fed marshes and helped maintain them (Hastings, 1959). Down-cutting of 15

Fig. 3. General topographical features of the San Bernardino Ranch. Dotted lines represent access roads; dots represent artesian sources (after unpublished USFWS map of SB Ranch).

17 the river channel separated its waters from those of the springs (USFWS,

1980), and must have lowered the water table thus influencing riparian cienega habitats (Hendrickson and Minckley, 1983).

Black Draw is presently undergoing active down-cutting, especially during the summer wet season. Except during flooding, Black Draw is dry

in its northern reaches on the SB Ranch and its channel is porous and sandy. During the past 3 years, the lower 2 km (1.2 miles) has had sustained flows (USFWS, 1980).

Eight spring areas which currently support or recently supported marsh vegetation are present on the SB Ranch. Historically they fed and maintained extensive cienegas (cinegas) or marshlands (Hastings,

1959; Hendrickson and Minckley, 1983). Through impoundment and chan- nelization of the springs and through draining of wetlands, only remnants of marshlands remain today. Two wells (Middle Well, Cottonwood

Well), five springs (Border Springs (2), Tule Spring, Pipe Spring,

North Slough Spring), and two open ponds (House Pond, North Pond) are shown in Fig. 3 and discussed below. Names of sites and measurements of flow rates are from USFWS (1980).

House Pond, largest of two open water sites, lies below the summit of the Mesa on the western end of the SB Ranch. It has been impounded since the late 1890's and is fed by at least three springs. Seasonal flood waters enter the pond by an ephemeral wash, and leave the SB

Ranch via House Creek. Non-flood overflow drains into a small canal east of the spillway. House Pond is slightly less than 1.0 ha (2.5 acres) surface area, with a maximum depth of 2.0 m (7 ft). Average -1 flow leaving the pond is -190 1 min . 22 winters. Winter precipitation is derived from cold frontal systems from the north and west. During summer, precipitation falls in the form of convection-induced afternoon thundershowers. Moist, unstable air from the south is rapidly heated over surrounding mountains, producing sudden, often violent, and generally localized storms. Although no snowfall was recorded in 1981, small amounts of snow have been recorded in winter months, with an annual average of 19 mm.

Because of prevailing drought in spring, the amount of herbaceous vegetation is dependent upon winter precipitation. Diversity and bio- mass of vegetation again increases with onset of summer rains in late

June or early July. The most floristically productive months in terms of density and diversity are July, August, and September. GEOLOGY

Geology of the SB Ranch consists mainly of Upper Paleozoic gyp- siferous limestones and Cretaceous sedimentary and metamorphic deposits, overlain by Quaternary sediments and volcanic accumulations (Imlay,

1939). Limestone outcrops are exposed in the eastern uplands, but it is mainly Quaternary formations which comprise most of the surface as revealed by well logs. Two Quaternary geologic formations prevail: valley fill and volcanics (Sauer, 1930).

Valley fill is of such immense depths that its exact nature and extent are unknown (Sauer, 1930). At the SB Ranch, valley fill consists of stream deposits, buried lake beds, and lava beds. Stream deposits are alluvial accumulations which have been washed from surrounding mountains and primarily consist of poorly rounded, coarse fan gravel, inter- bedded with sands and clays (Sauer, 1930). Buried lake beds are fine clays from both ephemeral ' playas' and permanent lakes. A 15 m-thick stratum of fine compact clay was penetrated at 93 m to 100 m below the surface in all wells drilled on the SB Ranch in the 1880's (Meinzer and

Kelton, 1913). Many acidic lava flows rest directly upon stream deposits, and all wells at the SB Ranch penetrated such a sheet at some depth above the lake deposits (Meinzer and Kelton, 1913).

Volcanic accumulations different from buried acidic type occur on the surface of the western third of the SB Ranch, providing evidence for another epoch of volcanic activity. These are composed mainly of olivine basalt, tuffs, ash, and breccias (Cooper, 1959), and are so recent they have not been buried nor greatly weathered. Prior to this volcanic period the valley was partially dissected basin, whose waters 24 had begun to trench the valley fill. This surface was then covered and smoothed by layers of ash and lava (Sauer, 1930). Waters of Black

Draw have since reinitiated basin trenching; the Mesa of the SB Ranch represents an excavated lava terrace, the broad alluvial base of which is rapidly eroding (Sauer, 1930).

In addition to relatively recent volcanism, the San Bernardino

Valley and indeed the entire area of southern Arizona and northern

Sonora have been subjected to recent seismic activity. In 1887, an i ntense earthquake struck northern Sonora, Mexico. Epicenter of the disturbance was in Batepito Valley at the northern end of the Teras

Mountains, which represent the northern-most range of the Sierra Madre

(Goodfellow, 1888). Shockwaves influenced a surface area of 1,200,000

2 km , from Yuma, Arizona, to Mexico City (Bennett, 1977). The Slaughter ranch house instantly collapsed from the shockwaves. In addition to surface damage, the earthquake permanently altered the structure of the groundwater basin. Old sources of water reportedly disappeared and new ones were created; the latter was the case for SB Ranch (Goodfellow,

1 888). HYDROLOGY

Like surface waters, groundwater flows from the center of the San

-1 Bernardino Valley southward into Mexico at a slope of 5.1 m km (IBWC,

1 980). The valley floor around the SB Ranch is nearly at groundwater

l evel and springs thus issue forth at various locations. Wells dug in

the 1880's range from 104 m to 206 m in depth (Meinzer and Kelton, 1913), and are artesian (i.e., water flows by means of its own pressure). Ar-

tesian systems occur when run-off becomes trapped between non-porous

strata. Subterranean pressure from accumulating water forces groundwater to the surface through natural or drilled fissures in the strata.

High pressures may also result in above normal water temperatures; in

1 981 water temperatures of six artesian sources averaged 28.5°C.

Baseline water chemistry from eight artesian sources and from Black

Draw during 1981 are in Table 1. Artesian water samples analyzed were chemically identical, indicating they are probably all from the same groundwater system. Black Draw appears to be a separate system chem-

i cally dissimilar from the artesian.

Total dissolved solids (TDS), which represent the degree of min- eralization of the water, are low to moderate relative to those of

"typical" southwestern desert waters as discussed by Cole (1968).

Chloride, sulfate, and silica play only a minor role in TDS, all at concentrations of less than 10 milligrams per liter (mg 1 -1 ). Carbon- ates and bicarbonates, measured in terms of alkalinity, also are not

remarkably high. Of the four ions— sodium, potassium, calcium, and magnesium — only sodium is relatively high; calcium is next highest, fol-

l owed by magnesium and potassium. 26

-1 Table 1. Summary of water chemistry (each parameter as mg 1 ) and water temperature (°C) from the artesian sources (8 sample locations) and Black Draw (2 sample locations) at the San Bernardino Ranch, taken by the author in 1981. Data are presented as mean ± 1 S.D. for sample sizes of 8 (artesian) and 2 (Black Draw); replicate samples were not taken for cations.

Artesian Black Analysis System Draw

Total Dissolved Solids: Alkalinity 4.64 ± 0.23 7.18 ± 0.69 Chloride 8.10 ± 0.55 10.36 ± 1.62 Sulfate 5.0 ± 1.3 21.3 ± 7.5 Silica 3.80 ± 0.31 5.48 ± 0.11 Calcium 15.1 2.3 Magnesium 0.29 12.9 Sodium 70 58 Potassium 3.1 6.8

Total Dissolved Nutrients: Phosphate 0.005 ± 0.001 0.127 ± 0.015 Nitrate 1.116 ± 0.169 0.174 ± 0.031

Temperature 28.5 19.4 27

Nutrient levels (nitrates and phosphates) from artesian sources were also examined (Table 1). Nitrate levels were relatively high while phosphates were low as compared with average levels from Arizona streams (Grimm, et al., 1981). Layers of organic clays common throughout the valley may account for above average levels of nitrogen (Meinzer and Kelton, 1913). Low levels of phosphates are not understood (pers. comm., Nancy Grimm, 1982). VEGETATION

Classification and Successional Trends

Lands included in the SB Ranch as well as surrounding territory were considered by Benson and Darrow (1981) as desert grassland occur-

i ng between Chihuahuan Desert to the east and the Sonoran Desert to the west. These deserts are separated by a northern extension of the Mexican

Plateau, which forms the Continental Divide both north and south of the

International Boundary. However, a wide area of low elevations between the Upper Gila drainage in southeastern Arizona and the Rio Grande drainage in southwestern New Mexico allows occurrence of species characteris- tic of each desert. Taxa of the SB Ranch which are considered by Benson and Darrow (1981) to bridge the gap in the Continental Divide between the two deserts are Atriplex canescens, Ephedra trifurca, and Fouquieria splendens. (See "Catalogue of Vascular Plants" for complete name list-

i ngs). Limestone hills which prevail on the east side of the SB Ranch favor the growth of Chihuahuan Desert flora at elevations normally suit- able for grassland. These species include Acacia constricta, Flouren- sia cernua, Larrea divaricata spp. tridentata, and Ziziphus obtusifolia var. obtusifolia.

Recent vegetational changes attributable to human activity have occurred on the SB Ranch, especially in the last 100 years. Greatest disturbances have occurred in marshland and grassland habitats. Marsh- l and areas formed by seepage of surface artesian flows were drained and plowed for farmland or pasture. Only small, disturbed remnants of original marshland remain. Since 1980, when all cattle were removed, these once lush areas lay weed-covered or bare. Also, since the late 1800's 29

the ranges of the SB Ranch have been apparently overgrazed by livestock, contributing to depletion of ground cover, invasion of mesquite (Proso- pis glandulosa) and snakeweed ( Gutierrezia microcephala), and erosion of

the topsoil typical of the region (Gardner, 1950; Cable and Martin, 1973;

Smith and Schmutz, 1975; Chew, 1982).

The vegetation communities discussed in this work are consistent with those defined by Lanning (1981). Eight distinct communities lie within the confines of the SB Ranch (Table 2): (1) Desert Grassland;

(2) Chihuahuan Desert Scrub; (3) Riparian Forest/Woodland; (4) Mesquite

Bosque; (5) Riparian Scrub; (6) Marshland; (7) Aquatic; and (8) Old

Field/Disturbed. Distributions of these communities on the SB Ranch are given in Figs. 5 and 6.

Vegetation Analysis

Transect studies were carried out in communities 1, 2, 4, and 6 to quantify the density, cover, and importance of major species in these

i mportant community-types on the SB Ranch. Descriptions of other communities are based on qualitative observations and collections.

Transects i n Desert Grassland, Chihuahuan Desert Scrub, and Mes- quite Bosque communities were performed in June and October 1981, and were based on a plotless (point-quarter) technique (Oosting, 1956).

Transects were laid out near existing (flagged) bird- and mammal-census transects (Lanning, 1981). Along each line, 25 random points were de- marcated, and the nearest woody plant and grass (i.e., surveyed separ- ately) in each of the four quadrants were measured for distance from the central point and for canopy diameter. 30

Table 2. Communities of the San Bernardino Ranch (after Lanning, 1 981).

Communities ha % total

Desert Grassland 255 25

Chihuahuan Desert Scrub 385 39

Mesquite Bosque 220 22

Riparian Forest/ 7 0.7 Woodland

Riparian Scrub 1 0 1.0

Marshland 6 0.6

Aquatic 1 0.1

Old Field/Disturbed 110 11 31

Fig. 5. Vegetational communities for the western half of the San Bernardino Ranch (after Lanning, 1981).

KEY

---- diffuse change in vegetation

- clear change in vegetation

1 Desert Grassland

2 Chihuahuan Desert Scrub

3 Riparian Forest/Woodland

4 Mesquite Bosque

5 Riparian Scrub

6 Marshland

7 Aquatic

8 Old Field/Disturbed A 33

Fig. 6. Vegetational communities for the eastern half of the San Bernardino Ranch (after Lanning, 1981).

KEY

---- diffuse change in vegetation

clear change in vegetation

1 Desert Grassland

2 Chihuahuan Desert Scrub

3 Riparian Forest/Woodland

4 Mesquite Bosque

5 Riparian Scrub

6 Marshland

7 Aquatic

8 Old Field/Disturbed o Km 1

Point-quarter transects were performed in several locations in each major community. In the Desert Grassland, transects were done on the Mesa (Fig. 5) and on the northeastern section (Fig. 6). In the

Chihuahuan Desert Scrub, transects were done on the eastern, western, and central uplands (Figs. 5 and 6). In the Mesquite Bosque, transects were done on benches adjacent to Black Draw (Fig. 5) and Hay Hollow

Wash (Fig. 6).

Only the major cienega adjacent to Pipe Spring (Fig. 3) was sampled from the Marshland community-type. Since the vegetation coverage

0 was essentially 1 00/, plot sampling with a relative dominance index was utilized, based on the Braun-Blanquet releve method (Braun-Blan- quet, 1921). Ten random points were chosen along each of five reg-

2 ularly spaced lines, and the corner of a 1.0 m quadrat was placed at each point. Cover of each species within the quadrat was estimated and placed in an appropriate cover class (see Table 6).

Major Communities

Desert Grassland: this is defined as a community where vegetation cover was 50% grass with shrub cover less than 1 09 (Lanning, 1981).

Desert Grassland occurs primarily on the Mesa and on the northern boundary of the SB Ranch (Figs. 5 and 6). It occurs elsewhere in mosaic fashion, often in narrow strips between other communities, or scattered i n small isolated patches where favorable soils occur. These soils are generally deep, fine alluvium.

Dominant perennial grasses in this community were Hilaria mutica 36 and Muhlenbergia porteri, mixed with Bouteloua curtipendula, B. eriopoda, B. chondrosioides, Scleropogon brevifolius, and Sporobolus airoides (Table 3). Various other grasses collected in this community were:

Aristida purpurea E. pectinacea var. glauca Hilaria belangeri Bouteloua repens Setaria grisebachii Bothriochloa ishaemum Sitanion hystrix Diplachne dubia Sporobolus contractus Eragrostis barrelieri S. cryptandrus E. lehmanniana S. pulvinatus E. orcuttiana Trichachne californica

Dominant shrubs in the Desert Grassland were Acacia constricta,

Prosopis glandulosa, Opuntia phaeacantha var. major, and 0. leptocaulis.

Other woody and herbaceous taxa collected in the Desert Grassland were:

Anoda cristata K. hirsutissima A. pentaschista K. parviflora Amoreuxia palmatifida Microseris linearifolia Asclepias subverticillata Pectis filipes Astragalus allochrous var. subnuda A. nuttalliana Physalis pubescens Atriplex elegans var. integrifolia var. elegans Plantago patagonica Boerhaavia coulteri var. oblonga B. erecta Proboscidea arenaria Chamaesaracha coronopus P. parviflora Commelina erecta Rivinia humilus var. crispa Rynchosida physocalyx Corchorus orinocensis Senna bauhinioides Daucus pusillus Spermolepis echinata Dichlostemma pulchellum Sphaeralcea angustifolia Erodium cicutarium var. cuspidata Glandularium wrightii S. laxa lbervillea tenuisecta Talinum angustissimum Ipomoea costellata T. aurantiacum Isocoma heterophylla T. paniculatum Janusia gracilis Tidestromia lanuginosa Jatropha macrorhiza Yucca elata Kallstroemia grandiflora 37

Table 3. Desert Grassland transect data.

Density Cover Importance (#/ha) (%) Value

Shrub Species

Acacia constricta 504 3.2 213

Prosopis glandulosa 90 1.2 56

Opuntia phaeacantha 45 0.04 27 var. major

O. leptocaulis 6 0.01 4

Total 646 4.4

Grass Species

Hilaria mutica 1,960 1.67 240

Bouteloua barbata 590 0.05 52

Muhlenbergia porteri 30 0.07 8

Total 2,580 1.8 38

Chihuahuan Desert Scrub: this community dominates the eastern

uplands, central uplands, and the extreme western portion of the Mesa

(Figs. 5 and 6). The Chihuahuan Desert Scrub community forms the largest and most uninterrupted vegetation type, whose major constituents are Larrea, Flourensia, Acacia, and Prosopis, with a sparse understory of grasses. Soils are generally thin, shallow, and of limestone or

igneous origin.

Dominant shrub species were Larrea divaricata ssp. tridentata,

Flourensia cernua, Acacia constricta, Fouquieria splendens, and Gutier- rezia microcephala (Table 4). Other common shrubs were Prosopis glandulosa, Yucca elata, and Lycium andersonii var. wrightii. Important sub-shrubs were Parthenium incanum, Dyssodia acerosa, Machaeranthera pinnatifida, Leucelene ericoides, and Zinnia acerosa.

Following is a list of other non-graminoid taxa collected from this community:

Acacia neovernicosa Coryphantha vivipara Abutilon incanum var. bisbeeana Acourtia nana Croton pottsii Agave sp. var. pottsii Aloysia wrightii Cryptantha angustifolia Apodanthera undulata C. barbigera Argythamnia neomexicana C. crassisepala Asclepias nyctaginifolia C. micrantha Atriplex canescens C. muricata Bahia absinthifolia Cymopteris multinervatus Baileya multiradiata Dalea formosa B. pleniradiata D. pogonathera Boerhaavia intermedia Echinocereus fendleri B. wrightii var. rectispinus Caesalpinia gillesii Ephedra trifurca Calycoseris wrightii Eriastrum diffusum Carlowrightia arizonica Eriogonum abertianum Chaenactis stevioides E. polycladon Chamaesaracha sordida Eschscholzia cal ifornica Chenopodium fremontii ssp. mexicana Cleome multicaulis Euphorbia exstipulata Table 4. Chihuahuan Desert Scrub transact data.

Density Cover Importance (#/ha) (%) Value

Shrub Species

Larrea divaricata 4,630 1 0.2 1 47 ssp. tridentata

Flourensia cernua 1,920 4.5 69

Acacia constricta 930 2.4 34

Fouquieria splendens 290 2.9 1 3

Gutierrezia microcephala 280 0.2 9

Prosopis glandulosa 20 0.5 3

Yucca elata 20 0.3 2

Agave sp. 30 0.1 2

Total 8,740 22.8

Grass Species

Muhlenbergia porteri 1,060 8.4 1 30

Erioneuron pulchellus 2,640 0.3 109

Hilaria mutica 380 0.6 21

Bouteloua curtipendula 100 1.1 1 5

Sporobolus cryptandrus 1 40 0.1 8

S. airoides 60 0.1 4

Total 4,630 1 0.9 40

E. micromera O. phaeacantha E. serrula var. discata E. setiloba O. phaeacantha Ferocactus wislizenii var. major Gilia sinuata O. spinosior Helianthus ciliaris O. violacea Heterotheca psammophila var. violacea Hibiscus denudatus Orobanche multiflora var. i nvolucellatus Pectocarya platycarpa Hoffmanseggia glauca Pectis cylindrica Hymenothrix wislizenii P. filipes Hymenoxys odorata var. subnuda Ipomopsis longiflora Peniocereus greggii Juniperus monosperma var. greggii Lappula redowskii Phacelia coerulea Lesquerella gordonii Plagiobothrys arizonicus L. purpurescens Polygala lindheimeri Linum lewisii var. parvifolia Lotus humistratus Porophyllum gracilis Malacothrix fendleri Portulaca umbraticola Mammillaria heyderi Sanvitalia abertii var. macdougalii Schistophragma intermedia Menodora scabra Sida procumbens Mollugo verticillata Streptanthus arizonicus Nama hispidum Tetraclea coulteri Oenothera primiveris Tiquilia canescens Opuntia kleiniae Verbesina rothrockii 0. l eptocaulis Zephyranthes longifolia

Understory perennial grasses most common in this community were

Muhlenbergia porteri, Hilaria mutica, Sporobolus airoides, and Bouteloua curtipendula. Erioneuron pulchellum was dominant in heavily overgrazed sites. Following is a list of the other grasses in the Chihuahuan

Desert Scrub community:

Aristida adscensionis Heteropogon contortus A. hamulosa Poa bigelovii Enneapogon desvauxii Schismus barbatus Eragrostis superba Sporobolus giganteus Erioneuron avenacum Tridens muticus var. l ongiaristatum

Mesquite Bosque: this community type has mesquite forming more

than 50% of the canopy cover, with the canopy usually over 2 meters of-

(6 feet) in height (Lanning, 1981). The understory is mostly bare

ground, or annuals. This community is conspicuous along Black Draw and

Hay Hollow Wash, invading adjacent grassland communities (Figs. 5 and

6). It is also along the canal from House Pond. Mesquite flourishes

i n deep, sandy soils, usually adjacent to watercourses, where it forms

dense thickets.

Mesquite formed almost 1 00% of the vegetation cover in two tran-

sects (Table 5), with its canopy covering up to 80% of the ground sur-

face. Other shrubs and trees were Larrea divaricata ssp. tridentata,

Celtis reticulata, Ziziphus obtusifolia var. obtusifolia, and Rhus

microphylla. Less common woody plants were Sambucus mexicana, Mimosa

biuncifera, Bumelia lanuginosa var. rigida, and Morus microphylla.

Comprising the understory were annual grasses, such as Panicum hirti-

cauli, Eragrostis lutescens, Setaria macrostachya, Eriochloa lemmoni

var. gracilis, and Panicum obtusum. The common perennial grass was

Sporobolus airoides. Herbaceous ground cover, occurring mostly in

shaded areas, consisted of Ruellia nudiflora var. glabrata, Acalypha

ostraefolia, A. neomexicana, Tetrameria hispidum, and Commicarpus

scandens. Other herbaceous plants were:

Acourtia wrightii I. leptotoma Aristolochia watsoni Marselia vestita Bidens leptocephala Mentzelia albicaulis Boerhaavia cocci nea Phacelia arizonica Clematis drummondii Phaseolus angustissimus Echinopepon wrightii Phorodendron cal ifornicum Eupatorium greggii Physalis acutifolia Euphorbia prostrata Sarcostemma crispum Ipomoea barbatisepala Solidago wrightii I. coccinea Verbena scabra I. costellata Viguiera dentata 42

Table 5. Mesquite Bosque transect data.

Density Cover Importance Species (#/ha) (%) Value

Prosopis qlandulosa 463 0.717 290

Celtis reticulata 6 0.002 6

Larrea divaricata 6 0.001 4 ssp. tridentata Total 475 0.720 — Riparian Forest Woodland: this community consists of mature stands of Populus fremontii and Salix gooddingii, which are scattered along the banks of northern Black Draw, Hay Hollow Wash, and adjacent to active artesian wells, excepting Border Springs (Figs. 5 and 6).

From a sampling of mature trees in the community, Populus fremontii

( N = 9) averaged approximately 15 m in height with a diameter at breast height (DBH) of 42 cm. Salix gooddingii (N = 6) averaged about 7 m in height with a DBH of 24 cm.

Riparian Scrub: this community consists of dense stands of Popu- l us fremontii and Salix gooddingii saplings, mixed with the riparian shrubs Baccharis salicifolia, Hymenoclea monogyra, and Tamarix chinensis. Common grasses were Sorghum halapense, Eragrostis neomexicana, and Poa bigelovii. This community is distinct from the Forest/Woodland i n that Riparian Scrub constituents thrive in the moist stream channel of Black Draw and Hay Hollow Wash (Figs. 5 and 6), rather than along the banks. The stream channels of both Black Draw and Hay Hollow Wash are highly disturbed and support a lush growth of often weedy, herbaceous plants:

Allophyllum gilioides Helenium thurberi Artemisia ludoviciana Melilotus albus Conyza canadensis M. i ndicus Corydalis aureum Mentzelia pumila Datura meteloides Nicotiana trigonophylla Erigeron divergens Sorghum bicolor Helianthus annuus Stephanomeria pauciflora

Marshland or Cienega: this community comprises a small but ecolo- gically important part of the SB Ranch (Figs. 5 and 6). It includes all areas of land permanently inundated by non-impounded artesian water, 44 and supports lush stands of vegetation. Soils are thick, dark, organic, and often relatively anaerobic. Many native aquatic taxa occur in the small marshland areas remaining at the SB Ranch.

A clear zonation of the vegetation occurs in the Marshland community. The two distinct areas are: (1) the zone directly in and around the water source; and (2) the areas away from the water source but with- i n its area of inundation (Table 6; Figs. 5 and 6). Around sources, the dominant emergents were Scirpus americanus and Bidens laevis.

Stands of Typha domingensis also commonly occurred there. Submergents i ncluded Zannichellia palustris and Potamogeton pectinatus.

In the cienega proper (i.e., zone 2 above), the dominants were

Eleocharis parishii, Cyperus niger var. capitatus, Aster pauciflorus,

Berula erecta, Aster subulatus, Cyperus odoratus, and Gnaphalium chi- l ensis. Other common plants were:

Anemopsis californica L. valdiviana Carex bolanderi Lepidium lasiocarpum C. praegracilis var. georginum Cyperus aristatus Mentha spicata Epilobium adenocaulon Mimulus guttatus Gnaphalium purpureum Myosurus minimus Heteranthera limosa Nasturtium officinale Juncus balticus Polygonum argythamnium var. montanus P. lapathifolium J. torreyi Rumex crispus Lemna gibba Veronica peregina L. minor ssp. xalapensis L. minuta Xanthium strumarium

Dominant grasses in the cienega were Paspalum distichum, Muhlen- bergia asperifolia, and Polypogon monspeliensis. Other grasses in this community included: Table 6. Marshland transect data. Percentage of sampled plots in each cover class for each taxon.

Cover Class 0 ab- Species >90% 75-90% 50-75% 25-50 1 0-25% 1-1o% <1% sent

Eleocharis parishii 14 1 8 20 8 1 0 12 6 1 2 Scirpus americanus 1 0 4 6 lo 8 20 6 36 Cyperus niger 0 0 10 1 0 20 28 4 28 var. capitatus Aster pauciflorus 0 0 0 0 o 40 16 44 Paspalum distichum 0 0 0 2 8 1 6 12 62 Bidens laevis 0 10 6 2 0 2 lo 80 Berula erecta 0 0 0 0 o 14 24 62 Aster subulatus 0 0 0 2 0 10 1 0 78 Muhlenbergia asperifolia 2 2 0 0 2 4 6 84 Polypogon monspeliensis 0 0 0 0 0 0 14 86 Cyperus odoratus 0 0 0 0 o 4 o 96

Agrostis exarata Echinochloa colon urn var. minor E. crusgalli A. semiverticillata Eragrostis cilianensis Arundo donax E. l utescens Distichlis spicata Phalaris caroliniana ssp. stricta

Aquatic: this community/habitat is composed of the two small open water sites on the SB Ranch, House Pond and North Pond. It differs from marshland communities in that its water is completely contained.

A few plant taxa are found locally at these two sites and not at any other on the SB Ranch. Waters of House Pond are covered during the warmer months with Nymphaea odorata which was introduced into the pond i n the late 1800's. Lilaeopsis recurva also occurs in and around this particular pond only. At North Pond, locally abundant Najas marina covers substrate in the shallow edges.

Old Field/Disturbed: these areas of disturbance are primarily previously cultivated fields and land around buildings (Lanning, 1981;

Figs. 5 and 6). They support seasonally lush, often monotypic stands of weedy annuals. The dominants observed at these sites were Salsola i berica, Amaranthus palmeri, Chenopodium incanum, Ambro- sia confertiflora, Helianthus annuus, Descurainea pinnata, D. sophia,

Portulaca suffrutescens, P. retusa, and Tribulus terrestris. Other herbaceous plants in these distrubed areas were:

Allionia incarnata Baccharis sarothroides Alternanthera repens Centaurea melitensis Amaranthus torreyi Chenopodium leptophyllum Argemone pleiacantha Cirsium ochrocentrum Asparagus officinalis Convolvulus arvensis Astragalus thurberi C. equitans Atriplex elegans Conyza coulteri var. thornberi Cucurbita digitata A. wrightii C. foetidissima 47

Cuscuta umbellata Senecio douglasii Euphorbia albomarginata var. douglasii E. florida S. douglasii E. heterophylla var. l ongilobus E. hyssopifolia Sisymbrium irio E. serpyllifolia Solanum eleagnifolium Gaura parviflora Sonchus asper Lactuca serriola S. oleraceus Lepidium thurberi Suaeda torreyana Marrubium vulgare Trianthema portulacastrum Monolepis nuttalliana Verbena plicata Rumex hymenosepalus Verbesina encelioides var. exauriculata

Grasses in these areas were:

Bothriochloa saccharoi des Hordeum .ubatum Bromus rubens H. leporinum B. tectorum Leptochloa filiformis B. wildenowii Paspalum dilatatum Chloris virgata Poa annua Cynodon dactylon Setaria glauca Diplachne fascicularis Trichloris crinita Festuca pratensis

Cultivated plants within the confines of the ranch house yard were not collected. RECOMMENDATIONS FOR PROTECTION OF THE SB RANCH

Despite the relatively recent effects of disturbance by grazing and cultivation, which have steadily eroded existing native communities, the SB Ranch has maintained a diverse and rich native flora.

For example, of the grasses collected, 70% were native to Arizona.

However, Desert Grasslands and Marshlands have been especially impact- ed by past disturbances and their continued existence depends upon protection from further degradation.

Grazing pressures have allowed mesquite to expand and flourish.

Since pressures of both grazing and cultivation have been removed, management to prevent further mesquite invasion of Desert Grassland should be initated.

Procedures to expand marshland habitats have been proposed by the

USFWS (1980). With proper management the marshlands may expand to near former status. But suggestions have also been made to clear certain aquatic habitats which are currently felt by some fish biologists to be "choked" with vegetation. These clearing efforts should be i mplemented only with a balanced perspective in mind, as some of the plant taxa which appear quite common to the community are uncommon to this area of the Southwest (e.g., Heteranthera limosa, Aster pauciflorus). CATALOGUE OF VASCULAR PLANTS

The known vascular flora of the SB Ranch and immediate vicinity consists of 353 taxa representing 235 genera from 72 families (Table

7). The number of taxa for the ten best represented families is presented in Table 8. Approximately 1000 specimens have been studied.

Thirteen collecting trips were made between June 1980 and March 1982.

A total of 33 days were spent collecting in the SB Ranch area, with some in all months except December and January. All specimens collected by the author are in the Herbarium of Arizona State University (ASU).

In addition, the author has seen the following collections: 73 collections made by Larry Toolin of The Nature Conservancy (ARIZ), and a small number made by Thomas Daniel, Elinor Lehto, and Donald J. Pinkava (ASU).

Two previously unconfirmed species for Arizona were collected during the course of the study. Corchorus orinocensis H.B.K. (Til- iaceae) was found in the grasslands below the summit of the Mesa. It was only speculated to occur in Arizona from a collection made by

Pringle in 1884, who gave the location only as "sandy plains near the

Mexican Boundary" (Kearney, Peebles, and collaborators, 1951). Another unconfirmed species which was collected in the grasslands -20 meters north of the SB Ranch was lbervillea tenuisecta (Gray) Small (Cucur- bitaceae). Tom Van Devender also recently collected this species in the mountains east of Douglas (pers. comm., 1982).

The following catalogue of vascular plants is arranged alphabet- ically for ease of use. Benson (1982) was used to identify the Cacta- ceae, Hitchcock (1964) for Gramineae, and Kearney, Peebles, and collaborators (1951) for the remainder. Nomenclature follows that of the 50

Table 7. Taxonomic composition by major categories of the flora of the San Bernardino Ranch.

Number of Number of Number of Class Families Genera Taxa

Pteriodphyta 1 1 1

Gymnospermae 2 2 2

Angiospermae 69 232 350

Monocots 13 53 95

Dicots 56 1 79 255

Total 72 235 353 51

Table 8. Taxonomic composition by the ten largest families represented at the San Bernardino Ranch.

Number of Number of % of Taxon Genera Taxa Total # Taxa

Gramineae 35 69 20

Compositae 43 55 16

Leguminosae 11 1 7 5

Euphorbiaceae 5 1 5 4

Cactaceae 6 11 3

Chenopodiaceae 5 1 0 3

Cruciferae 6 9 3

Boraginaceae 5 9 3

Solanaceae 6 1 0 3

Cyperaceae 5 8 2

Total 1 25 211 62 52

Catalogue of the Flora of Arizona (Lehr, 1980) and supplements to that catalogue (Lehr and Pinkava, 1981; 1982). Recent revisions have been followed whenever possible. Accompanying each entry in the list are the following:

A. I mportant synonymy— generally names that have been recently superceded.

B. Common names— if available.

C. Relative adundance (Rel. Abun.) within the indicated community type: Common (C) = widespread and abundant throughout the indicated type; Occassional (0) = scattered throughout the indicated type; Un- common (U) = known in the study area from one or a few localities;

Rare (R) = known from one area after being diligently searched for;

Local (0 = occurring in restricted habitats.

D. Vegetational association (Veg. Assoc.) in which the taxon has been collected: Desert Grassland (DG); Chihuahuan Desert Scrub (CDS);

Mesquite Boque (MB); Riparian Forest/Woodland (RFW); Riparian Scrub (RS);

Marshland (M); Aquatic (A); and Old Field/Disturbed (OFD).

E. Code letters and collection numbers indicating the following collectors whose specimens are deposited at the indicated herbaria:

L = Elinor Lehto and D.J. Pinkava (ASU); M = Gayle Marrs Smith (ASU);

T = Larry Tool in (ARIZ); D = Thomas Daniel (ASU). Herbarium code letters follow Index Herbariorum (Homgrcn and Kenden, 1 974). Collections made nearby but out of the study area are indicated by "+". Taxa i ntroduced via cultivation are followed by "*"; those felt by the author to be 'sensitive' to disturbance, by "**". Although no plants collected are Federally listed as endangered, these 'sensitive' taxa 53 are worthy of protection due to their restricted habitats and unique- ness. Rel. Veg. Abun. Assoc. FILICINAE

MARSILEACEAE

Marsilea vestita Hook. 6 Grey. (M. mucronata A. Br.) -- Pepperwort. Black Draw, MB along shaded bank; (M1211).

GYMNOSPERMAE

CUPRESSACEAE

Juniperus monosperma (Engelm.) Sarg. One-seed Juniper. Scattered along stony, CDS north-facing hills; (M598).

EPHEDRACEAE

Ephedra trifurca Torr. -- Long-leaved Joint-fir. (M423, 424, 520, 570, 596). 0 CDS

ANGIOSPERMAE

MONOCOTYLEDONAE

AGAVACEAE

Agave palmeri Engelm. (m648). 0 CDS Rel. Veg. Abun. Assoc.

Yucca elata Engelm. Soaptree Yucca, Palmilla. (1568). 0 DG/CDS

AMARYLLIDACEAE

Zephyranthes longifolia Hemsl. -- Plains Rain Lily. Open ground; (M786). CDS

COMMELINACEAE

Commelina erecta L. var. crispa (Woot.) Palmer & Steyer. Herbadel Polio. DG (M745, 746, 836).

CYPERACEAE

Carex bolanderi Olney -- Sedge. (1703).

C. praegracilis W. Booth -- Sedge. (M474, 610, 621; T693). 0

Cyperus aristatus Rottb. -- Yellow Yew Grass. (M853, 1105). 0

C. niger R. & P. var. capitatus (Britt.) O'Neil -- Flat Sedge. (M322, 323).

C. odoratus L. -- Flat Sedge. (M218, 219, 311, 320, 321, 927, 1115; 1700).

Eleocharis parishii Britt. -- Spikerush. (L24496; M377, 407-409, 638, 664).

Scirpus americanus Pers. (including S. olneyi Gray) -- Bulrush. (M451, 498; T824). C Rel. Veg. Abun. Assoc. GRAMINEAE

Agrostis exarata Inn. var. minor Hook. -- Spikebent. (M1085). C M

A. semiverticillata (Forsk.) C. Char. -- Water Bent. (M555, 557; 1669, 692). 0 M/MB

Aristida adscensionis L. -- Six-weeks Three-awn. (M993, 1 041, 1158). C CDS

A. purpurea Nutt. var. glauca (Nees) A. Holmgr. & N. Holmgr. (A. glauca (Nees) C DG Walp.) -- Reverchon Three-awn. (M1036).

A. hamulosa Henr. (M997). 0 CDS

Arundo donax L. -- Giant Reed. Moist depression in grassland; (M1192). 0 M/DG

Bothriochloa ischaemum (L.) Keng. (Andropogon ischaemum L.) (M1198). 0 DG

B. saccharoides (Swartz) Rydb. (Andropogon saccharoides Swartz) -- Silver C MB/OFD Beardgrass. (M612, 1 072, 1084).

Bouteloua aristidoides (H.B.K.) Grisb. -- Six-weeks Needle Grama. (M824, 828, C DG 829).

B. barbata Lag. -- Six-weeks Grama. (M814, 826, 890, 1 032). C DG/CDS

B. chondrosioides (H.B.K.) Benth. (M891, 942, 947). C DG

B. curtipendula (Michx.) Torr. -- Side-oats Grama. (M720). C DG

B. eriopoda (Torr.) Torr. -- Black Grama. (M779, 893, 921, 1 051). C DG Rel. Veg. Abun. Assoc.

B. repens (H.B.K.) Scribn. & Merr. (B. filiformis (Fourn.) Griffiths) -- Slender 0 DG Grama. (11721).

B. rubens L. -- Red Brome, Foxtail Chess. (11427). OFD

B. tectorum L. -- Downy Chess. (11606). OFD

B. wildenowii Kunth (B. catharticus Vahl) -- Rescue Grass. (M438, 527, 605; OFD T665).

Chloris virgata Swartz -- Feather Fingergrass. (M340, 818, 884, 1 091, 1107). OFD

Cynodon dactylon (L.) Pers. -- Burmuda Grass. Moist sites; (M560, 1094).* OFD

Diplachne dubia (Kunth) Scribn. (Leptochloa dubia (H.B.K.) Nees) -- Green 0 DG Spangletop. (M881, 1 078).

D. fascicularis (Lam.) Beauv. (Leptochloa fascicularis (Lam.) Gray) -- Beaded OFD Spangletop. (11628, 928, 1 068, 1087).

Distichlis spicata (L.) Greene ssp.• stricta (Torr.) Thorne (D. spicata (L.)

Greene var. stricta (Torr.) Beetle) -- Desert Saltgrass. (11 1139, 1284).

Echinochloa colonum (L.) Link -- Jungle Ricegrass. (M637). 0

E. crusgalli (L.) Beauv. -- Barnyard Grass. Moist sites; (M216, 217, 1116; 1691) 0 M/OFD

Enneapogon desvauxii Beauv. -- Spike Pappusgrass. (M888, 935, 1149, 1194). CDS Veg. Assoc.

Eragrostis barrel ieri Daveau. (M1054). 0 DG

E. cilianensis (All.) Mosher -- Stinkgrass. (M319, 622, 1 090, 1102). C OFD

E. lehmanniana Nees -- Lehmann's Lovegrass. (M1197). 0 DG

E. l utescens Scribn. (M848, 1111). 0 DG

E. neomexicana Vasey. Black Draw channel; (M835, 1189). 0 RS

E. orcuttiana Vasey. (M892, 894, 1 089). 0 DG

E. pectinacea (Michx.) Nutt. (including E. diffusa Buckl.). (M951). 0 DG

E. superba Peyr. Moist depressions; (M1275, 1277). R CDS

Eriochloa lemmoni Vasey & Scribn. var. gracilis (Fourn.) Gould (E. gracilis 0 MB (Fourn.) Hitchc.). (M819, 943).

Erioneuron avenaceum (H.B.K.) Takeoka var. longiaristatum (Kurtz) Beetle (var.

grandiflorum (Vasey) Gould; Tridens grandiflorus (Vasey) Woot. & Standl.). U CDS

(M961).

E. pulchellum (H.B.K.) Takeoka (Tridens pulchellus (H.B.K.) Hitchc.) -- Fluff- CDS grass. (M675).

Festuca pratensis Huds. (F. elatior L.) -- Meadow Fescue. (M613; 1666). C OFD Rel. Veg. Abun. Assoc.

Heteropogon contortus (L.) Beauv. Tanglehead. (M1163). U CDS

Hilaria belangeri (Steud.) Nash -- Curly Mesquite. (M833). C DG

H. mutica (Buckl.) Benth. Tobosagrass. (M719, 754, 1 061). C DG/CDS

Hordeum jubatum L. -- Fox-tail Barley. (1613, 698). 0 OFD

H. leporinum Link -- Wild Barley. (M436; 1668). C OFD

Leptochloa filiformis (Lam.) Beauv. -- Red Spangletop. (M862, 880, 917, 1 056). C OFD

Muhlenbergia asperifolia (Nees & Mey.) Parodi Scratchgrass. (M675, 1118,

1186).

M. porteri Scribn. -- Bush Muhly. (M708, 711, 783, 841, 1200). C DG/CDS

Panicum hirticaul Presl. Open areas; (M771, 889, 906, 981, 987). 0 MB

P. obtusum H.B.K. -- Vine Mesquite. (M683, 728, 887). 0 OFD/MB

Paspalum dilatatum Poir. -- Dallis Grass. Moist sites; (M1103). 0 OFD

P. distichum L. -- Knotgrass. (M224, 336, 343; T689, 835).

Phalaris caroliniana Walt. -- Carolina Canary Grass. (M607). 0

Poa annua L. -- Annual Bluegrass. Moist sites; (M412, 413, 514). 0 OFD

P. bigelovii Vasey & Scribn. Bigelow's Bluegrass. Black Draw channel; (1617). 0 RS Rel. Veg. Abun. Assoc.

Polypogon monspeliensis (L.) Desf. Rabbitfoot Grass. (M470, 661; 1656).

Schismus barbatus (L.) Thell. -- Mediterranean Grass. (M416). C CDS

Scleropogon brevifolius Phil. -- Burrograss. (M1070, 1199). C DG

Setaria grisebachii Fourn. Grisebach Bristlegrass. (M710, 904). 0 DG

S. glauca (L.) Beauv. (S. lutescens (Weigel.) Hubb). (M1095, 1104). U OFD

S. macrostachya H.B.K. -7 Plains Bristlegrass. Under shrubs; (M210, 469, 558; DG/MB/ CDS 1705).

Sitanion histrix (Nutt.) J.G. Smith -- Squirrel-tail. (M569; 1660). 0 DG

Sorghum bicolor (L.) Moench (S. vulgare Pers.). Black Draw channel; (M1206)* R RS

S. halepense (L.) Pers. -- Johnson's Grass. (M512, 576). C RS

Sporobolus airoides (Torr.) Torr. -- Alkali Sacaton. (M556, 559, 608, MB/CDS 963, 1039; 1830).

S. contractus Hitchc. -- Spike Dropseed. (M1079, 1214). 0 DG

S. cryptandrus (Torr.) Gray -- Sand Dropseed. (1664). 0 DG

S. giganteus Nash -- Giant Dropseed. Sandy soil; (M1022). U CDS

S. pulvinatus Swallen. (M1101). 0 DG Rel. Veg. Abun. Assoc.

Trichachne californica (Benth.) Chase -- Cottontop. (M763, 948). 0 DG

Trichloris crinita (Lag.) Parodi -- Feather Fingergrass. (M536, 609; T704). 0 OFD

Tridens muticus (Torr.) Nash -- Slim Tridens. (M778, 781, 782, 969, 1 018). 0 CDS

JUNCACEAE

Juncus balticus Willd. var. montanus Engelm. -- Wire Rush. (M5.21, 611).

J. torreyi Coville. (M665, 811).

LEMNACEAE

Lemna gibba L. -- Wingbags, Inflated Duckweed. (M369, 370, 380-384, 499).

L. minuta H.B.K. (L. minima Phil.) -- Duckweed. Tule Spring; (M308, 430).

L. minor L. -- Water Lentil. (M309).

L. valdiviana Phil. -- Duckweed. (M411).

LILIACEAE

Asparagus officinalis L. -- Asparagus. (M655).* R OFD Rel. Veg. Abun. Assoc.

Dichlostemma pulchellum (Salisb.) Heller Bluedick. Growing among tufts of DG Hilaria mutica; (M601, 1228, 1229; 1620).

NAJADACEAE

Najas marina L. -- Holly-leaved Water Nymph. North Pond and North Slough; A (M220).

PONTEDARIACEAE

Heteranthera limosa (Swartz) Willd. -- Mud Plantain. Especially common at the 0 Border Springs; (M213, 214, 223, 313-315, 318, 390-392).

POTAMOGETONACEAE

Potamogeton pectinatus L. -- Sago Pondweed. Close to water source; (M225, 402- 0 406, 845). Rel. Veg. Abun. Assoc. TYPHACEAE

Typha domingensis Pers. -- Southern Cattail. Close to water source; (M619, 654;

T836).

ZANNICHELLIACEAE

Zannichellia palustris L. -- Common Pool Mat. Close to water source; (M361-364,

393-401; T618).

DICOTYLEDONAE

ACANTHACEAE

Carlowrightia arizonica Gray. Under shrubs; (M1155). U CDS

Ruellia nudiflora (Engelm. & Gray) Urban var. glabrata Leonard. Shaded sites; MB (M682, 735, 960).

Tetrameria hispidum Nees. Under shrubs; (M578, 582, 1 066, 1207). 0 MB Rel. Veg. Abun. Assoc. AIZOACEAE

Moilugo verticillata L. -- Indian Chick Weed. Under shrubs; (M312, 767, 1048). 0 CDS

Trianthema portulacastrum L. -- Verdolago Blanca. Open ground; (M748, 749, OFD/DG/ CDS 861, 1011, 1 063).

AMARANTHACEAE

Alternanthera repens (L.) Kuntze Khakiweed. Open ground; (M604). 0 OFD

Amaranthus palmeri Wats. -- Palmer's Amaranth. (M705, 706, C OFD

A. torreyi (Gray) Benth. -- Torrey's Amaranth. (M1014). 0 OFD

Tidestromia lanuginosa (Nutt.) Standl. (M678). C OFD/DG

ANACARDIACEAE

Rhus microphylla Engelm. -- Desert Sumac. (M549, 1236). 0 MB

ARISTOLOCHIACEAE

Aristolochia watsonii Woot. & Stand]. -- Indian Root. (11716, 718). R MB Rel. Veg. Abun. Assoc. ASCLEPIADACEAE

Asclepias nyctaginifolia Gray. (M785, 1180). CDS

A. subverticillata (Gray) Vail -- Poison Milkweed, Western Whorled Milkweed. 0 DG (M310, 634, 1 081).

Sarcostemma crispum Benth. (Funastrum crispum (Benth.) Schlechter) -- Climbing MB Milkweed. (M530, 531, 589, 805).

BORAGINACEAE

Cryptantha angustifolia (Torr.) Greene -- Narrow-leaved Cryptantha. Sandy soil; CDS (M463, 494, 652).

C. barbigera (Gray) Greene -- Bearded Crypthantha. Sandy soil; (M515 p 422a). 0 CDS

C. crassisepala (T. & G.) Greene -- Thick-sepaled Cryptantha. Sandy soil; CDS (m444, 852, 1220).

C. micrantha (Torr.) Johnst. -- Purple-rooted Crypthantha. (T663). 0 CDS

C. muricata (H. & A.) Nels. & Macbr. (1621). 0 CDS

Lappula redowskii (Hornem.) Greene -- Stickseed. Sandy soil; (M420, 422, 493, CDS 504, 508, 1246.) Rel. Veg. Abun. Assoc.

Pectocarya platycarpa Munz. & Johnst. -- Broad-nutted Comb Bur. (1623). 0 CDS

Plagiobothrys arizonicus (Gray) Greene -- Bloodweed, Arizona Popcorn Flower. 0 CDS (T622).

Tiquilia canescens (DC.) A. Richardson (Coldenia canescens DC.) -- Shrubby 0 CDS Colderia. (M780, 796).

CACTACEAE

Coryphantha vivipara (Nutt.) B. & R. var. bisbeeana (Orcutt) L. Benson. (photo CDS only).

Echinocereus fendleri Engelm. var. rectispinus (Peebles) L. Benson -- Pincushion CDS Cactus. Under shrubs; (M1287).

Ferocactus wislizenii (Engelm) B. & R. -- Barrel Cactus. (photo only). U CDS

Mammillaria heyderi Muehlenfordt var. macdougalii (Rose) L. Benson (M. gum- CDS mifera Engelm. var. macdougalii (Rose) L. Benson. (M1241).

Opuntia kleiniae DC. -- Pencil Cholla (M617).* R CDS

O. leptocaulis DC. -- Desert Christmas Cactus. Under shrubs; (M542, 616, 717). C CDS Rel. Veg. Abun. Assoc.

O. phaeacantha Engelm. var. discata (Griffiths) Benson & Walkington. (M1256). U CDS

O. phaeacantha Engelm. var. major Engelm. (M1258). 0 CDS/DS

O. spinosior (Engelm.) Toumey -- Cane Cholla. (T831). 0 CDS

O. violacea Engelm. var. violacea Engelm. (M1257). 0 CDS

Peniocereus greggii (Engelm.) B. & R. var. greggii (Cereus greggii (Engelm.) CDS var. greggii). (M1288).**

CAPRIFOLIACEAE

Sambucus mexicana Presl. -- Mexican Elder. Dry area around Twin Pond; (M485). MB

CHENOPODIACEAE

Atriplex canescens (Pursh.) Nutt. -- Four-wing Saltbush. (M532, 713, 1034; 0 CDS T827).

A. elegans (Moq.) Dietr. var. elegans. (M693, 899). C DG

A. elegans (Moq.) Dietr. var. thornberi Jones. (M701). C OFD

A. wrightii Wats. (M1174). C OFD Rel. Veg. Abun. Assoc.

Chenopodium fremontii Wats. (11581, 671, 1264, 1265). C CDS

C. incanum (Wats.) Heller var. elatum Crawford (C. fremontii Wats. var. incanum OFD Wats.). (11623).

C. leptophyllum (Nutt. ex Moq.) S. Wats. -- Slimleaf Goosefoot. (11526). C OFD

Monolepis nuttalliana (Schult.) Greene -- Poverty Weed. (11431, 462; T671, 684, OFD 706).

Salsola iberica Sennen & Pau -- Russian Thistle, Tumbleweed. (11338). C OFD

Suaeda torreyana S. Wats. -- Seep Weed. (M1285). C OFD

CLEOMACEAE

Cleome multicaulis DC. (C. sonorae Gray). (T8334-).** CDS

COCHLOSPERMACEAE

Amoreuxia palmatifida Moc. & Sesse. (A. palmatifolia M. & S.). (M772, 774, 832). 0 DG Rel. Veg. Abun. Assoc. COMPOSITAE

Acourtia nana (Gray) Reveal & King (Perezia nana Gray). Under shrubs; (M490, 517, CDS 599).

A. wrightii (Gray) Reveal & King (Perezia wrightii Gray). Hay Hollow Wash; MB (M1042).

Ambrosia confertiflora DC. (Franseria confertiflora (DC.) Rydb.) Slimleaf OFD Bursage. (M926, 944, 1177).

Artemisia ludoviciana Nutt. Sandy soil; (M1209, 1210). RS

Aster pauciflorus Nutt. -- Marsh Alkali Aster. (M222, 331, 562, 564, 565;

T823).**

A. subulatus Michx. var. ligulatus Shinners (= A. exilis).(M1097, 1109,1117,1121). 0

Baccharis salicifolia (R. & P.) Pers. (B. glutinosa Pers.) -- Seep Willow. RS Black Draw; (M815, 964, 1119).

B. sarothroides Gray -- Desert Broom. (M429). OFD

Bahia absinthifolia Benth. (M495, 765, 792, 837, 842, 846, 918, 1050). CDS

Baileya multiradiata Nary. & Gray -- Desert Marigold. Sandy soil; (M584, 591, 0 CDS 804; 1832). Rel. Veg. Abun. Assoc.

B. pleniradiata Harv. & Gray --Woolly Marigold. (M1165, 1166). 0 CDS

Bidens laevis (L.) B.S.P. -- Bur Marigold. Close to water source; (M208; 1826).

B. leptocephala Sherff. Beggertick, Spanish Needles. 534, 1159). 0 MB

Calycoseris wrightii Gray -- White Tack Stem. (M488, 1230, 1238; 1685, 703). 0 OFD/CDS

Centauria melitensis L. -- Malta Star-thistle. (M642). 0 CDS

Chaenactis stevioides H. & A. (M1223; 1702). 0 CDS

Cirsium ochrocentrum Gray -- Yellow Spine Thistle. (M552, 614, 620). 0 OFD

Conyza canadensis (L.) Cronq. (Erigeron canadensis L.). Black Draw; (M325, 1029, 0 RS 1 067).

C. coulteri Gray. Moist sites; (M631, 1074). 0 OFD

Dyssodia acerosa DC. -- Dogweed, Fetid Marigold. (M507, 590). C CDS

Erigeron divergens T. & G. -- Spreading Fleabane. Hay Hollow Wash, sandy soil; 0 RS ( M415, 629, 662, 670, 1248; 1672).

Eupatorium greggii Gray. Shaded sites; (M1272, 1273). U MB

Flourensia cernua DC. -- Tarbush. (M1269-1271). C CDS

Gnaphalium chilense Spreng. -- Small-flowered Cudweed, Cottonbatting. (M630; 0 T829). Rel. Veg. Abun. Assoc.

G. purpureum L. -- Purple Cudweed. (11561).

Gutierrezia microcephala (DC.) Gray -- Three-leaf Snakeweed. (M344, 995, 1 013). C CDS

Helenium thurberi Gray -- Sneezeweed. Black Draw; (M580; T662). U RS

Helianthus annuus L. -- Common Sunflower. (M1099). C RS/OFD

H. ciliaris DC. -- Plains Sunflower. Under shrubs; (M809, 1 059). 0 CDS

Heterotheca psammophila Wagenkn. (H. subaxillaris (Lam.) Britt. & Rusby sensu 0 CDS K. & P.) -- Camphor Weed. (111031).

Hymenoclea monogyra T. & G. -- Burrobush. Hay Hollow Wash; (M1213). C RS

Hymenothrix wislizenii A. Gray. (M1049 C RS

Hymenoxys odorata DC. -- Bitterweed. (M418, 472, 478, 483, 509, 563, 676, OFD/CDS 1655). isocoma heterophylla (A. Gray) Greene. (M959, 1086). C DG

Lactuca serriola L. (M659, 744, 1113). 0 OFD

Leucelene ericoides (Torr.) Greene (Aster hirtiflorus Blake; A. arenosus (He]- CDS ler) Blake) -- White Aster, Roseheath. (M501, 776, 791, 1254; T697).

Machaeranthera pinnatifida (Hook.) Shinners. (11502, 511, 669, 714, 715, 1035). C CDS Rel. Veg. Abun. Assoc.

Malacothrix fendleri Gray. (M486, 1233; 1676). C CDS

Microseris linearifolia (DC.) Schultz Bip. -- Silver Puffs. (T624). 0 DG

Parthenium incanum H.B.K. Mariola. (11760, 932, 936, 957). C CDS/DG

Pectis cylindrica (Fern.) Rydb. (M976, 996). U CDS

P. filipes Harv. & Gray var. subnuda Fern. (11823, 989; D1791). 0 DG/CDS

Porophyllum gracile Benth. (111026). 0 CDS

Sanvitalia abertii Gray. Under shrubs; (M777, 962). C CDS/DG

Senecio douglasii DC. var. monensis (Greene)Jepson--GroundseI. (M435, 1226). 0 OFD

Senecio douglasii DC. var. longilobus (Benth.) L. Benson -- Thread-leaf 0 OFD Groundsel. (M567, 615, 647).

Solidago wrightii Gray var. adenophora Blake -- Goldenrod. (M1188). U MB

Sonchus asper (L.) Hill -- Spiny Sow Thistle. Moist sites; (M371, 639, 663). 0 OFD

S. oleraceus L. -- Sow Thistle. Moist sites; (11727). 0 OFD

Stephanomeria pauciflora (Torr.) A. Nels. -- Desert Straw. (M594, 595). 0 RS

Verbesina encelioides (Cav.) Benth. & Hook. var. exauriculata Robins. & Greenm. OFD Crownbeard. (M632, 674, 952, 979; 1838). Rel. Veg. Abun. Assoc.

V. rothrockii Robbins. & Greenm. Crownbeard. (M593). U CDS

Viguiera dentata (Cav.) Spreng. (M649, 1134, 1138). 0 MB

Xanthium strumarium L. (X. saccharatum Wallr.) -- Common Cocklebur, Abrojo. 0 (M332, 333, 341).

Zinnia acerosa (DC.) Gray (Z. pumila Gray). (M506, 755). C CDS

CONVOLVULACEAE

Convolvulus arvensis L. -- Field Bindweed. (M586, 603, 641). 0 OFD

C. equitans Benth. (C. incanus Vahl). Moist sites; (M1080, 1083, 1112, 1215). 0 OFD

Ipomoea barbatisepala Gray. Open sites; (M330, 865, 882, 896, 1009). 0 MB

I. coccinea L. -- Scarlet Morning Glory. (M897, 967). 0 MB

I. costellata Torr. (M821, 876, 898, 902, 923). 0 MB

I. leptotoma Torr. (M858, 859, 915, 919). 0 MB/OFD

CRUCIFERAE

Descurainia pinnata (Walt.) Britt. -- Yellow Tansy-mustard. (M417, 421). OFD Rel. Veg. Abun. Assoc.

D. sophia (L.) Webb. -- Flixweed. (M372; 1670). C OFD

Lepidium lasiocarpum Nutt. var. georginum (Rydb.) C.L. Hitch. -- Sandpepper

Grass. (M467).

L. thurberi Woot. Peppergrass. (M326, 410, 500, 538, 729; T675, 834). C OFD

Lesquerella gordonii (Gray) Wats. -- Gordon Bladderpod. (M376, 414, 419, 459, CDS/OFD 465, 503).

L. purpurea (Gray) Wats. -- Bladderpod. (M1251-1253). 0 CDS

Nasturtium officinale R. Br. (Rorippa nasturtium-aquaticum (L.) Schinz. & Thell.)

-- Water Cress. (M471, 473, 475).

Sisymbrium irio L. -- London Rocket. (M373, 737). C OFD

Streptanthus arizonicus Wats. -- Twist-flower. (M492, 1227). C CDS

CUCURBITACEAE

Cucurbita digitata Gray -- Finger-leaved Gourd. Shaded sites; (1724). 0 OFD

C. foetidissima H.B.K. -- Buffalo Gourd. Shaded sites; (M600). 0 OFD Rel. Veg. Abun. Assoc.

Echinopepon wrightil (Gray) Wats. -- Wild Balsam Apple. (M1040, 1044, 1 047, 1057, 0 MB 1088, 1141).** lbervillea tenuisecta (Gray) Small. (M1196+).** DG

CUSCUTACEAE

Cuscuta umbellata H.B.K. var. reflexa (Coult.) Yunker -- Umbrella Dodder. OFD Entwined about Salsola; (M1136).

EUPHORBIACEAE

Acalypha neomexicana Muell. Arg. -- New Mexican Copperleaf. Shaded sites; (M877, 0 MB 925, 977, 1017, 1169).

A. ostraefolia Riddell -- Hornbeam. Shaded sites; (M784, 787, 820, 1 021, 1037, MB 1140).

Argythamnia neomexicana (Muell. Arg.) Heller. (M525, 574, 750, 963, 955). 0 CDS/DG

Croton pottsii (Klotzsch) Muell. Arg. var. pottsii (C. corymbulosus Engelm) -- 0 CDS Leather Weed. (M 988, 1008, 1045, 1065, 1157). Rel. Veg. Abun. Assoc.

Euphorbia albomarginata T. & G. -- Rattlesnake Weed. (M487, 651, 849). C OFD

E. exstipulata Engelm. (M968, 1012). 0 OFD

E. florida Engelm. (M1191). 0 CDS

E. heterophylla L. -- Painted Spurge. (M870, 871). 0 OFD

E. hyssopifolia L. -- Hyssop Spurge. 01688, 766, 856, 860, 883, 1160, 1161). C OFD/CDS

E. micromera Boiss. -- Sonoran Sandmat. (11972, 1120). 0 OFD/CDS

E. prostrata Ait. -- Ground-fig Spurge. Under shrubs and trees; (M812, 1144, MB/CDS 1145).

E. serpyllifolia Pers. (M704, 847, 874, 965, 1 019). C OFD/CDS

E. serrula Engelm. Sawtooth Spurge. (M1001, 1003, 1025). C CDS

E. setiloba Engelm. -- Bristle-lobed Sandmat. (11 1002, 1073, 1179). 0 CDS

Jatropha macrorhiza Benth. (11802, 808). 0 DG

FOUQUIERIACEAE

Fouquieria splendens Engelm. -- Coach Whip. West desert; (11597). C CDS

Rel. Veg. Abun. Assoc. FUMARIACEAE

Corydalis aurea Willd. -- Golden Corydalis. Moist sites; (M460, 461, 479). U RS/M

GERANIACEAE

Erodium cicutarium (L.) L'Her. -- Filaree. (M496). C DG/CDS

HYDROPHYLLACEAE

Nama hispidum Gray. Open sites; (M481, 677, 678, 1232; T616). C CDS

Phacelia arizonica Gray. Open sites; (M464). 0 MB

P. coerulea Greene. Sandy soil; (M445, 518, 1 247). C CDS

LAB IATAE

Marrubium vulgare L. -- Horehound. (M541, 645). 0 OFD

Mentha spicata L. -- Spearmint. (M1123, 1124, 1137). 0 M Rel. Veg. Abun. Assoc. LEGUMINOSAE

Acacia constricta Benth. -- White Thorn. (M571, 756). C CDS/DG

A. neovernicosa Isley (A. vernicosa Standl.). (1837). 0 CDS

Astragalus allochrous Gray -- Half-moon Loco. (1699). 0 DG

A. nuttallianus Nutt. -- Locoweed. (1678). 0 DG

A. thurberi Gray -- Locoweed. (M454-456, 458; 1695). C OFD

Caesalpinia gillesii (Wall ex Hook.) Dietrich (C. gillesii Wall.) -- Bird of CDS Paradise. (M838).*

Dalea formosa Torr. -- Feather Plume. (M592). R CDS

D. pogonathera Gray -- Bearded Dalea. (M978, 980). 0 CDS

Hoffmanseggia glauca (Ort.) Eifort (H. densiflora Benth.) -- Hog Potato. (M484, CDS/OFD 497, 553; 1686).

Lotus humistratus Greene -- Hill Locust. (M505, 1225). 0 CDS

Melilotus albus Desr. ex Lam. (M. albus Desr.) -- White Sweet Clover. Moist OFD sites; (M658).

M. indicus (L.) All. -- Annual Yellow Sweet Clover, Moist sites; M374, 452, OFD 453; 1659) Rel. Veg. Abun. Assoc.

Mimosa biuncifera (Benth.) B. & R. -- Wait-a-minute Bush. (M540, 730, 924). R MB

Phaseolus angustissimus Gray -- Bean. (M1167, 1168). 0 MB

Prosopis glandulosa Torr. (P. juliflora (Swartz) DC. var. glandulosa (Torr.) MB Ckll.) -- Honey Mesquite. (M539).

Senna bauhinioides (Gray) Irwin & Barneby (Cassia bauhinioides Gray) -- Two- 0 DG leaf Desert Senna (M762, 764).

LINACEAE

Linum lewisii Pursh. -- Flax. (M1224). CDS

LOASACEAE

Mentzelia albicaulis Dougl. -- Small-flowered Blazing Star. (M466, 468, 577; MB/DG T626).

M. pumila (Nutt.) T. & G. -- Stickleaf. (M602, 679). 0 RS Rel. Veg. Abun. Assoc. MALVACEAE

Abutilon incanum (Link) Sweet -- Indian Mallow. (M806, 807, 873, 916, 950, 974). C CDS/DG

Anoda cristata (L.) Schlecht -- Spurred Anoda. (M901, 954, 1122, 1185). 0 DG

A. pentaschista Gray. (M857, 907, 929, 930, 1146). 0 DG

Hibiscus denudatus Benth. var. involucellatus Gray -- Rock Hibiscus. (M970, 971, 0 CDS 985, 1150).

Rhynchosida physocalyx (Gray) Fryxell (Sida physocalyx Gray). (M741, 1024, 1235). 0 DG

Sida procumbens Swartz. Under shrubs; (M770, 966, 1148, 1171-1173). C DG/CDS

Sphaeralcea angustifolia (Cav.) G. Don var. cuspidata Gray -- Narrow-leaved DG Globe Mallow. (M329, 537, 625, 1136; T657).

S. l axa Woot. & Stand]. -- Caliche Globe Mallow. (M1062, 1216). C DG

MALPIGHIACEAE

Janusia gracilis Gray. (M958). 0 DG/CDS

Rel. Veg. Abun. Assoc. MARTYNIACEAE

Proboscidea arenaria (Engelm.) Decne. -- Devil's Claw, Cinco Llagas. (M334, 0 DG 757).

P. parviflora (Woot.) Woot. & Stand]. -- Devil's Claw, Cinco Llagas. (M825, DG 839).

MORACEAE

Morus microphylla Buckl. -- Texas Mulberry. (M575). MB

NYCTAGINACEAE

Allionia incarnata L. (M698, 699, 733, 739, 769, 910, 912, 913). OFD

Boerhaavia coccinea Mill. -- Red Spiderling. (M903, 1 027, 1030, 1033, 1038, MB/OFD 1135).

B. coulteri (Hook. f.) Wats. -- Coulter's Spiderling. (M691, 702, 703, 743, OFD/DG 768).

B. erecta L. (M680, 761, 1131-1133). OFD/DG

Rel. Veg. Abun. Assoc.

B. intermedia Jones -- Five-winged Ringstem. (M689, 690, 692, 723). OFD/CDS

B. wrightii Gray -- Large-bracted Boerhaavia. (M1058). CDS

Commicarpus scandens L. Shaded areas; (M529, 533, 587, 588, 938, 940, 941, 1129, MB 1130).

NYMPHAEACEAE

Nymphaea odorata Ait. -- White Water-lily. House Pond; (M585).* L A

OLEACEAE

Menodora scabra Gray. (M800, 984, 991). C CDS

ONAGRACEAE

Epilobium adenocaulon Hausskn. (M1278-1282). 0 M

Gaura parviflora Dougl. -- Lizard-tail, Velvet Leaf Gaura. (M1178, 1183, 1184). U OFD

Oenothera primiveris Gray -- Large Yellow Desert Primrose. (T619). U CDS

Rel. Veg. Abun. Assoc. OROBANCHACEAE

Orobanche multiflora Nutt. (M1028). u CDS

PAPAVERACEAE

Argemone pleiacantha Greene -- Bluestem Pricklepoppy. (M324). 0 OFD

Eschscholzia californica Cham. ssp. mexicana (Greene) C. Clark (E. mexicana 0 CDS Greene) -- Mexican Gold Poppy. Stony soil; (M482; 1658).

PHYTOLACCACEAE

Rivinia humilus L. -- Coralito. Under shrubs; (M685, 686, 731, 863, 864, 866 0 DG 1 082, 1143).

PLANTAGINACEAE

Plantago patagonica Jacq. var. oblonga (Morris) Shinners (P. purshii R. & S. 0 DG var. picta (Morris) Pilger) -- Plantain. (M442, 522; 1683).

Rel. Veg. Abun. Assoc. POLEMONIACEAE

Allophyllum gilioides (Benth.) A. & V. Grant (Gilia gilioides (Benth.) Greene) 0 RS -- Straggling Gilia. (1611, 680).

Eriastrum diffusum (Gray) Mason. (M443, 583). CDS

Gilia sinuata Dougl. (M491, 1222). 0 CDS

Ipomopsis longiflora (Torr.) V. Grant (Gina longiflora (Torr.) G. Don) -- 0 CDS White-flowered Gilia. (M489, 668).

POLYGALACEAE

Polygala lindheimeri Gray var. parvifolia Wheelock (P. tweedyi Britt.) -- 0 CDS Milkwort. (M789).

POLYGONACEAE

Eriogonum abertianum Torr. (M524, 673, 758, 830, 1154; T707). C DG/CDS

E. polycladon Benth. -- Sorrel Eriogonum. (M1181, 1182). 0 CDS

Polygonum argyrocoleon Steud. Silversheath Knotweed. (m666; 1661).

P. lapathifolium L. -- Willow Smartweed. House Pond along banks; (M337). Rel. Veg. Abun. Assoc.

Rumex crispus L. -- Curly Dock. (M545, 551, 618). 0

R. hymenosepalus Torr. -- Wild Rhubarb. (M1243). 0 OFD

PORTULACACEAE

Portulaca retusa Engelm. -- Western Pusley. (M738,840, 939). C CDS/OFD

P. suffrutescens Engelm. (M759). C OFD

P. umbraticola H.B.K. (P. coronata Small). (M753, 973, 1010). C CDS

Talinum angustissimum (Gray) Woot. & Standl. (M788, 1004, 1005).** 0 CDS/DG

T. aurantiacum Engelm. -- Flame Flower. (M712, 747, 872, 908, 975, 986, 1006). 0 DG

T. paniculatum (Jacq.) Gaertn. -- Pink Baby Breath. (M867, 875, 1077, 1217). 0 DG

RANUNCULACEAE

Clematis drummondii T. & G. -- Texas Virgin Bower. (M546-548). 0 DG

Myosurus minimus L. -- Mousetail. (M387-389, 425, 447). 0 MB Rel. Veg. Abun. Assoc. RHAMNACEAE

Ziziphus obtusifolia (Cook ex T. & G.) A. Gray var. obtusifolia -- Graythorn. C MB (M450, 477, 550, 626).

SAL ICACEAE

Populus fremontii Wats. -- Broadleaf Cottonwood. (M1244). C RFW

Salix gooddingii Ball -- Goodding's Willow. (M375, 426, 428, 439, 476). C RFW

SAPOTACEAE

Bumelia lanuginosa (Michx.) Pers. var. rigida Gray -- Gum Bumelia. (M573, 646, C MB 653).

SAURURACEAE

Anemopsis californica (Nutt.) H. & A. var. subglabra Kelso. -- Yerba-mansa. o ti (M209, 215, 316; T688). Rel. Veg. Abun. Assoc. SCROPHULARIACEAE

Mimulus guttatus DC. -- Monkey Flower. (M528, 543, 544; 1696). 0

Schistophragma intermedia (Gray) Pennell. (M982, 983). 0 CDS

Veronica peregrina L. ssp. xalapensis (H.B.K.) Pennell -- Necklace Weed. (M385, 0 386, 448, 449; 1694).

SOLANACEAE

Chamaesaracha coronopus (Dunal) Gray -- Small Groundcherry. (M751). 0 DG

C. sordida (Dunal) Gray (C. coniodes (Moric.) Britt.) -- False Nightshade. (M510, 0 CDS 684, 794, 1055, 1060).

Datura meteloides DC. -- Sacred Datura. Black Draw; (M566). U RS

Lycium andersonii Gray var. wrightii Gray -- Anderson Thornbush. (M801, 817). 0 MB/CDS

Nicotiana trigonophylla Dunal -- Desert Tobacco. Black Draw; (M650). U RS

Physalis acutifolia (Miers.) Sandw. (P. wrightii Gray) -- Wright Ground Cherry. 0 MB/OFD (M327, 328, 816, 852, 885, 1 007, 1175).

P. pubescens L. var. i ntegrifolia (Dunal) Waterfall (P. pubescens L.) -- Hairy 0 DG Ground Cherry. (M1015, 1016, 1142). Rel. Veg. Abun. Assoc.

Solanum elaeagnifolium Cav. Silverleaf Nightshade. (M554, 843, 844). 0 OFD

TAMARICACEAE

Tamarix chinensis Loureio. (T. pentandra sensu K. & P.) -- Salt Cedar. (M660). RS

TILIACEAE

Corchorus orinocensis H.B.K. (M855, 945).** DG

ULMACEAE

Celtis reticulata Torr. Net-leaf Hackberry. (M342, 457). 0 MB

UMBELLIFERAE

Berula erecta (Huds.) Coville -- Water Parsnip. (M211, 212, 339; T825).

Cymopterus multinervatus (Coult. & Rose) Tidestrom -- Purple Cymopterus. (M1249, CDS 1250).

Daucus pusillus Michx. -- Wild Carrot. (M434, 437). 0 DG Rel. Veg. Abun. Assoc.

Lilaeopsis recurva A.W. Hill. House Pond; (M378, 379, 643, 644).** L A

Spermolepis echinata (Nutt.) Heller. (M446, 516, 523; T679). 0 DG

VERBENACEAE

Aloysia wrightii (Gray) Heller -- Wright Lippa, Organillo. (M998-1000). R CDS

Glandularia wrightii (Gray) Umber (Verbena wrightii Gray) -- Desert Verbena. DG (M433, 480, 1221).

Tetraclea coulteri Gray. (M992). C CDS

Verbena plicata Greene -- Fanleaf Vervain. Moist sites; (M810, 851). U OFD

V. scabra Vahl -- Sandpaper Verbena. (M1125-1128). 0 MB

VISCACEAE

Phorodendron californicum Nutt. -- Desert Mistletoe. Growing in Prosopis; MB (M1239+, 1240+). Rel. Veg. Abun. Assoc. ZYGOPHYLLACEAE

Kallstroemia grandiflora Torr. -- Orange Caltrop. (M317, 694, 732, 909). C OFD/DG

K. hirsutissima Vail -- Carpetweed. (M831, 933).** u DG

K. parviflora Norton. (M742, 900). U DG

Larrea divaricata Cav. var. tridentata (Sesse & Moc. ex DC.) Felger & Lowe (L. CDS tridentata (DC.) Coville) Creosotebush, Greasewood. (11572).

Tribulus terrestris L. -- Goathead. (M695-697, 740). C OFD LITERATURE CITED

Aldrich, L.D. 1851. A Journal of the Overland Route to California. Mich, Univ. Microfilms, Ann Arbor.

Bartlett, J.R. 1854. Personal Narrative of Explorations and Incidents in Texas, New Mexico, California, Sonora, and Chihuahua. 2 vols. D. Appleton & Co., New York.

Bennett, E.F. 1977. An afternoon of terror. The Sonoran earthquake of May, 1887. Arizona and the West, Summer: 107-120.

Benson, L. 1982. The Cacti of the United States and Canada. Stanford Univ. Press, Stanford, Calif.

, and R.A. Darrow. 1981. Trees and Shrubs of the Southwestern Deserts. 3d ed. Univ. Ariz. Press, Tucson.

Bourke, J.G. 1886. An Apache Campaign in the Sierra Madre. New York.

Box, M.J. 1869. Adventures and Explorations in New and Old Mexico. James Miller, New York.

Braun-Blanquet, J. 1921. Plant Sociology. McGraw-Hill, New York.

Cable, D.R., and S.C. Martin. 1973. Invasion of semidesert grassland by velvet mesquite and associated vegetation changes. J. Ariz. Acad. Sci. 8: 127-134.

Chew, R.M. 1982. Changes in herbaceous and suffrutescent perennials in grazed and ungrazed desertified grassland in southeastern Arizona, 1958-1978. Amer. Midl. Nat. 108: 159-169.

Cochise County Parks Advisory Commission. 1980. Feasibility Study: San Bernardino Ranch. Bizbee, Arizona. 20 p.

Cole, G.A. 1968. Desert Limnology. In: G.W. Brown, Jr., ed., Desert Biology, Vol. 1, Chpt. IX, pp.— 23-486. Academic Press, New York.

Cooke. P.S.-G. 1848. Report of Lieut. Col. P. St. George Cooke of His March from Santa Fe, New Mexico, to San Diego, Upper California. House Exec. Doc. N. 41, 30 Congress, 1st Session.

Cooke, R.U., and R.W. Reeves. 1976. Arroyos and Enviromental Change in the American Southwest. Oxford Univ. Press, London, England.

Cooper, J.R. 1959. Reconnaissance Geologic Map of Southeastern Cochise County, Arizona. Mineral Investigations Field Studies Map- MF 213. United States Geologic Survey, Washington, D.C. 92

Emory, W.H. 1857. Report on the United States and Mexican Boundary Survey. U.S. 34th Cong., 1st Sess. House Ex. doc. 135. Washing- ton, D.C.

Erwin, A.A. 1965. The Southwest of John H. Slaughter, 1841-1922. A.H. Clark Co., Glendale, California.

Froebel, J. 1859. Seven Years' Travel in Central America, North Mexico and the Far West of the United States. Richard Bentley, London.

Gardner, J.L. 1950. Effects of thirty years of protection from grazing in desert grassland. Ecology 31: 44-50.

Goodfellow, G.E. 1888. The Sonoran earthquake, 1887. Science 9: 162- 1 67.

Gregor, K. 1958. The waters of the San Bernardino. Arizona Highways.

Grimm, N.B., S.G. Fisher, and W.L. Minckley. 1981. Nitrogen and phos- phorus dynamics in hot desert streams of southwestern U.S.A. Hydrobiologia 83: 303-312.

Hastings, J.R. 1959. Vegetation change and arroyo cutting in southeastern Arizona. J. Ariz. Acad. Sci. 1: 60-67.

Hendrickson, D.A., W.L. Minckley, R.R. Miller, D.S. Siebert, and P.H. Minckley. 1980. Fishes of the Rio Yaqui basin, Mexico and United States. Transactions Ariz.-Nev. Acad. Sci.

, and W.L. Minckley. 1983. Cienegas— vanishing climax communities of the American Southwest. Desert Plants 5: in press.

Hitchcock, A.S. 1950. Manual of the Grasses of the United States. 2nd ed. Revised by Agnes Chase, Dover Publications, Inc., New York.

Homgren, P.K., W. Kenden, and E.K. Schofield (compilers). 1981. Index Herbariorum. Part I. The Herbaria of the World. 7 ed. Bohn, Scheltema & Holkema, Utrecht/Antwerpen; Junk Publ. The Hague/ Boston. 452 pp. Regnum Vegetabile 106.

I mlay, R.W. 1939. Paleogeographic studies in northeastern Sonora. Bull. Geol. Soc. Am. 50: 1723-1744.

International Boundary Water Commission. 1979. Consideration of need for division of water resources of San Bernardino Valley Basin, Arizona between the United States and Mexico. Preliminary Report. El Paso, Texas. 12 pp. 93

Kearney, T.J., R.H. Peebles, and collaborators. 1 951. Arizona Flora. Univ. Calif. Press, Berkeley, 2nd ed. with Supplement by J.T. Howell, E. McClintock, and collaborators, 1 960.

Lanning, D.V. 1981. The Vertebrates of San Bernardino Ranch, Cochise County, Arizona. (Prepared for The Nature Conservancy and the United States Fish and Wildlife Service, Contract No. 1 4-16-0002- 81-213).

Lehr, J.H. 1978. A Catalogue of the Flora of Arizona. Desert Botanical Gardens, Arizona.

, and D.J. Pinkava. 1980. A catalogue of the flora of Arizona. Supplement I. J. Ariz.-Nev. Acad. Sci. 15: 17-31.

, and D.J. Pinkava. 1982. A catalogue of the flora of Arizona. Supplement I. J. Ariz.-Nev. Acad. Sci. 17: 19-26.

Mearns, E.A. 1907. Mammals of the Mexican Boundary of the United States. A Descriptive Catalog of the Species of Mammals Occurring in that Region, with a General Summary of the Natural History and List of Trees. U.S. Nat. Mus. Bull. 56, part 1.

Meinzer, 0.E., and F.C. Kelton. 1 913. Geology and Water Resources of the Sulfur Springs Valley, Arizona. United States Geologic Survey, Water Supply Papers 320: 9-213.

Oosting, J.J. 1956. The Study of Plant Communities. 2nd ed. Freeman, San Francisco.

Powell, H.M.T. 1931. The Santa Fe Trail to California, 1 849-1852. Grabhorn Press, San Francisco.

Sauer, C. 1 930. Basin and range forms in the Chiricahua area. Univ. Calf. Publ. in Geogr. 3: 339-387.

Sellers, W.D., and R.E. Hill (eds.). 1 974. Arizona Climate: 1 931-1972. 2nd ed. Univ. Ariz. Press, Tucson.

Smith D.A., and E.M. Schmutz. 1975. Vegetation changes on protected versus grazed desert grassland ranges in Arizona. J. Range Manage. 28: 453-458. Torrey, J. 1 859. Botany of the Boundary. United States and Mexican Boundary Survey. Washington, D.C.

United States Fish and Wildlife Service. 1 980. Management plan for aquatic habitats of San Bernardino Ranch, Douglas, Arizona. 1 9 pp.

Wagoner, J.J. 1975. Early Arizona-- Prehistory to Civil War. Univ. Ariz. Press, Tucson. • I .

ADDENDUM

MONOCOTYLEDONAE

CYPERACEAE

Cyperus esculatus L. (M1176). Occassional, Marshland.

LILIACEAE

Allium sp. (M1218). Occassional, Chihuahuan Desert Scrub.

Yucca sp. (picture only). Uncommon, Chihuahuan Desert Scrub.

DICOTYLEDONAE

BORAGINACEAE

Cryptantha albida (H.B.K.) Johnst. (M440). Occassional, Chihuahuan

Desert Scrub.

Eucrypta sp. (M1255). Occassional, Chihuahuan Desert Scrub.

CACTACEAE

Opuntia leptocaulis DC. (p. 66) var. tetracantha (Tourney) W.T. Marshall.

COMPOSITAE

Bahia absinthifolia Benth. (p. 69) (incl. var. dealbida).

CUCURBITACEAE

Apodanthera undulata Gray. (M793, 1023). Uncommon, Chihuahuan Desert

Scrub.

LEGUMINOSAE

Astragalus wootonii Sheldon. (M513, 519). Occassional Chihuahuan Desert

Scrub.

MALVACEAE

Malva sp. (M1235). Occassional, Chihuahuan Desert Scrub.

RHAMNACEAE

Condalia sp. (M1201). Mesquite Bosque at Black Draw, Uncommon. 95 SOLANACEAE

Solanum americanum Mill. (M534, 535, 1 076). Occassional, Mesquite

Basque near Cottonwood Well.

S. rostratum Dunal. (M1164). Occassional, Mesquite Basque near

Cottonwood Well. BIOGRAPHICAL SKETCH

Gayle Ellen Marrs-Smith was born in Phoenix, Arizona, on October 26, 1954. She received her elementary and secondary education in the Scottsdale Public Schools. In 1973 she entered Arizona State University, graduating with a Bachelor of Science in 1978. She worked as biological technician for the United States Fish and Wildlife Service in the Phoenix office of Ecological Services from 1978 to 1980. In 1980 she entered Arizona State University to pursue a Master of Science in botanical systematics and worked as water chemistry technician for the Department of Zoology. She is married.