NO. 3 DUNKLE : PLANT ECOLOGY, CHANNEL ISLANDS 297 



the same species which occur in similar situations on the mainland. 

 Typical genera are Lupiniis, Gilia, Cryptantha, Trifoliurti, Amsinckia, 

 Lepidium, Phacelia, Nemophila, Platystemon, Eschscholtzia, Caulanthus, 

 Thysano carpus, Lithophragma, Layia, Orthocarpus, Viola, and Gna- 

 phalium. 



Savannas 



The grasslands very frequently merge by imperceptible degrees into 

 shrub savannas. Various low shrubs and suffrutescents from the coastal 

 sagebrush form a low shrub savanna, the species of which vary with 

 different habitats and different islands. Plate 5a shows such a typical 

 low shrub savanna on the western island of Anacapa. The light colored 

 shrubs at the right are Aplopappus canus, with a typical, rounded clump 

 of Eriogonum arborescens in the rear center, and with Baccharis pilu- 

 laris consanguinea at right left. 



On islands where chaparral shrubs occur, isolated specimens will 

 be spaced through the grassland on the terraces and mesas, particular- 

 ly on the slopes of ridges. Ceanothus, Rhamnus, Crossosoma, Adenos- 

 toma, Rhus, and Photinia are most frequently found in such areas. 



Broad upland valleys frequently have scattered trees and arborescent 

 shrubs forming a tree savanna. Pinus muricata often forms open sa- 

 vannas on Santa Rosa and Santa Cruz Islands, and with it are often 

 interspersed large, rounded, arborescent sclerophylls such as Arctosta- 

 phylos diversifolia, Quercus agrifolia, Photinia arbutifolia, and Cerco- 

 carpus betuloides. On Santa Catalina a similar association exists but is 

 dominated by Quercus MacDonaldii, arborescent forms of Quercus 

 dumosa, Prunus Lyonii, Photinia arbutifolia macrocarpa, Cercocarpus 

 betuloides, C. betuloides multiflorus, C. alnifolius, Ceanothus megaca- 

 pus insularis, and Rhajnnus megacarpus insularis. On San Clemente 

 Island Quercus tomentella, Q. chrysolepis, and Photinia arbutifolia 

 form very small areas of savanna. These savannas are usually on terraces 

 or on rolling hills about wide upland watercourses. The trees most 

 frequently occupy slopes or swales where they receive some protection 

 from the wind. 



Marshes 



There are salt marshes or salt lagoons on Santa Catalina, San Cle- 

 mente, San Nicolas, Santa Rosa, and Santa Cruz islands. All of these 

 marshes are rather temporary in their nature and no endemics occur. 



