As a modern student of the flora of southern California, I too have felt the need for a book on the native plants of this region, particularly the coastal area of Los Angeles County and Orange County (part of Los Angeles County until about 1904). Therefore, the geographic focus of the fourth edition is on such places as the Los Angeles River, Ballona Creek, Santa Monica, Redondo Beach, San Pedro, Long Beach, and a few other coastal locations. As this edition is focused on coastal habitats, you will primarily see geographical notes about sand-dunes, beaches, marshes, swamps, cliffs, bluffs, rivers, creeks, sloughs, plains, prairies, meadows and "low places." I have excluded the lengthy morphology and taxonomic descriptions of the earlier editions because it simplifies the use of the book as an ecological, biogeographical, historical, and restoration manual.

The exact area included in this volume is the coast slope of Los Angeles and Orange Counties. This territory comprises a large portion of the great southern California valley, as well as the following mountain ranges, in each of which we name the culminating point: Sierra Santa Monica (Castro Peak 3946 fet.), Sierra San Fernando (San Fernando Peak 3793 ft.), Sierra San Gabriel (Mt. Gleason 6493 ft., San Gabriel Pak 6172 ft., Mt. San Antoniio 10800 ft.), Sierra Santa Ana (Santiago Peak 5675 ft.). Not a few of the more conspicuous and common plants of southern California not known to occur within our boundaries are included, however, so that the student will find that a great majority of the plants to be met with on the coast slope of Point Conception are described.

In the preparation of the text the author has made frequent use of published descriptions, especially original ones, only such changes being made as seemed necessary either on account of uniformity or to bring out unobserved characters. Published lists of our local flora have also been constantly consulted, but it is only justice to the author to say that he has personally collected nearly all the plants included in this work and has added many species not heretofore reported from our region. Duplicates of these specimens, as well as many others from southern California, are to be found in the Leland Stanford Jr. University Herbarium.

The author wishes to express his thanks to the following persons for assistance in various ways: Mr. S. B. Parish, Dr. A. Davidson, and Dr. H. E. Hasse for valuable notes; Miss Alice Eastwood for the privilege of examining the material in the California Academy of Sciences Herbarium; Dr. N. L. Britton, Dr. B. L. Robinson, Dr. E. L. Greene, Dr. P. A. Rydberg and Dr. J. K. Small for notes on doubtful forms; finally to Prof. William R. Dudley, who has not only given many critical notes and valuable suggestions which have aided greatly toward the completion of the work, but has also shown many personal favors which have rendered the task a pleasant one to the author.

2. P. flexilis .... Summits of San Gorgonio, San Jacinto and Santa Rosa Mountains.

3. P. monophylla .... (Nut Pine). Frequent on the desert slopes of the San Gabriel and San Bernardino Mountains.

4. P. quadrifolia ..... (Parry’s Pine). Santa Rosa Mountains, Hall. First collected at Larkin’s Station near the Mexican boundary by Parry.

5. P. torreyana ..... (Del Mar or Torrey Pine). Delmar, San Diego County; Santa Rosa Island.

6. P. ponderosa ... (Yellow Pine). Common on all our mountains, making up a greater part of the coniferous forests. The cones usually fall during the autumn and winter after maturity.

7. P. jeffreyi .... (Jeffrey Pine). Summits of San Gorgonio, San Jacinto and Santa Rosa Mountains.

8. P. murrayana .... (Murray Pine or Tamarack Pine). Frequent in the upper portions of the coniferous forests. Mt. San Antonio; Bear Valley; Mt. San Gorgonio; Mt. San Jacinto.

9. P. sabiniana ..... (Digger Pine or Silver Pine). Antelope Valley, ranging northward to the upper Sacramento. Confined to the foothills.

10. P. coulteri ..... (Coulter’s Pine). Rather frequent in the coniferous forests of the San Bernardino, San Jacinto and Cuyamaca Mountains, 4500-7000 feet altitude. Not yet reported from the San Gabriel Mountains.

11. P. attenuata ... (Knob-cone Pine). Extending in a narrow belt along the southern slope of the San Bernardino Mountains, 2500-4000 feet altitude.

Pseudotsuga macrocarpa ... (Big-Cone Spruce). Rather common in all our mountains except the Santa Monica. Ranging mostly from 2000-5000 feet altitude, being confined for the most part to canyons and north slopes in the upper portions of the chaparral belt and extending into the pine belt.

Abies concolor ... (White Fir). Frequent in the coniferous forests of the San Gabriel, San Bernardino, San Jacinto, and Cuyamaca Mountains.

Libocedrus decurrens ..... (Incense Cedar). Frequent in the coniferous forests of the San Gabriel, San Bernardino, San Jacinto and Cuyamaca Mountains.

Juniperus californica ... [California Juniper]. San Fernando Valley and San Gabriel Wash near the mouth of the canyon. Common on the desert slope.

J. occidentalis ... [Western Juniper]. Summit of Mt. San Antonio and in Bear Valley, San Bernardino Mountains.

T. angustifolia. [Narrow-leaved Cat-tail]. In similar places, but not common. Near Los Angeles, Davidson; San Bernardino, Parish.

Sparganium eurycarpum. Bur-Reed. Occasional along streams, usually growing with Typha. Ballona Creek; New River near Alamitos.*

P. lonchites. Pondweed. Occasional in ponds in the valley region.

P. foliosus californicus. Pondweed. Occasional in streams and irrigating ditches in our interior valleys. June-September.

P. pectinatus. Pondweed. Common in streams and ponds. May-August.

Ruppia maritima. Ditch-Grass. Brackish streams along the coast. June-August.

Zannichellia palustris. Horned Pondweed. Occasional in marshes and ponds.

Naias flexilis. Naiad. Near Soldiers’ Home, Hasse, Davidson.

Zostera marina. Eel-Grass. Shoal waters in bays on muddy bottoms. San Pedro.

Phyllospadix torreyi. [Surfgrass]. Growing on rocks which are uncovered at low tide. San Pedro; La Jolla.

Triglochin maritima. Arrow-Grass. Salt marshes along the coast.

Lilaea subulata. Occasional about San Bernardino, Parish. Frequent about San Diego and in the Cuyamaca Mountains.

Lophotocarpus calycinus. (Sagittaria calycina). Ballona Creek.

Sagittaria latifolia. Arrow-Head Occasional on margins of ponds of Los Angeles.

Sitanion anomalum. Ballona Creek, near Mesmer, and on the South Fork of the Santiago Creek, Santa Ana Mountains.

Scirpus robustus. Common in marshes, especially in somewhat saline places. June-October.

Atriplex expansa. Occasional in the Ballona Marshes.

Atriplex microcarpa. Rather common in saline places toward the coast.

Atriplex californica. Occasional in saline places along the coast and on sandy bluffs overhanging the sea.

Atriplex breweri. Bluffs along the seashore. Port Los Angeles; Santa Monica; Port Ballona.

Dithyrea californica maritima. Occasional along the seashore between Redondo and Port Ballona.

Hutchinsia procumbens. In moist saline places throughout our range. March-April.

Lepidium lasiocarpum. Sand-dunes along the seashore.

Lepidium acutidens. In saline places toward the coast. Cienega; Santa Monica.

Horkelia sericea. Near Port Ballona, not otherwise known south of Santa Barbara. March-May.

Epilobium californicum. In marshes near the coast. Cienega, Davisdson. Alamitos.

Boisduvalia glabella. Low ground. Santa Monica; Mesmer; San Diego. July - October.

Astragalus brauntoni. Occasional in dry places in the Santa Monica Mountains, Hasse, Braunton.

Phacelia douglasii. Frequent near the coast along the borders of sand-dunes. Much resembling some of the large-flowered Nemophilas.

Phacelia fremontii. Los Angeles River; Wilson's Peak Davidson. Santiago Peak.

Conanthus stenocarpus. Growing about the borders of ponds. Santa Monica, Davidson; Soldiers Home.

Cryptantha leiocarpa. Frequent on the sand-dunes along the seashore.

Amsinckia spectabilis. Common in sandy soil near the coast, and apparently passing into the next.

Amsinckia intermedia. A very common weed in all the valleys and foothills.

Centromadia parryi australis. Brackish flats toward the coast.

Helianthus oliveri. Cienega; East Los Angeles.

Helianthus parishii. Oak Knoll, Grant. Rather frequent in the San Bernardino Valley.

Jaumea carnosa. Common in salt marshes along the coast.

Lasthenia chrysostoma. Rather common in open places in our coast valleys and foothills. Port Ballona; Santa Monica Mountains.

Lasthenia mutica. In sandy soil along the coast near Port Ballona; common about San Diego. April-May.

Lasthenia tenella. Sycamore Grove, Greata.

Lasthenia glabrata coulteri. Common in salt marshes, especially along the coast.

Pluchea camphorata. Occasional along streams and marshes about Los Angeles; Ballona Creek.

Psilocarphus globiferus. Frequentl on the plains and hills, especially in exsiccated places.

LeRoy Abrams (1874 to 1956) explored the Los Angeles region and southern California in his search for native plants more than a century ago. He traveled far and wide looking for trees, shrubs, rare plants, and new species in all kinds of different areas from 1898 to 1903. He visited seashores at Ballona, Santa Monica, Topanga, and down the coast to San Diego. He explored the highest peaks of southern California such as Mount Baldy. He explored the deserts, prairies, rivers, and plains of Los Angeles and vicinity. It was a time before automobiles and airplanes, and as professor at Stanford University, it meant that he would have had to ride a train to Los Angeles. After his arrival in Los Angeles, he traveled via horseback, horse-buggy, electric railroad, and on foot, totaling thousands of miles over the 5 year period.