33 



the islands. It is mostly open cultivated or grazing land with 

 isolated specimens or scattered clumps of trees and shrubs. It is 



heir that one finds the great sugar-cam- and pineapple planta- 

 tions. Introduced weeds also find conditions most congenial for 

 their development. Where sufficient moisture is present grass 

 may be more or less abundant. Shrubby thickets especially of 

 the introduced Lantana camara and Psidium guajava are abun- 

 dant along the bottoms and sides of gulches and valleys and the 

 introduced Opuntia megacantha Salm-Dyck is common in the 

 more arid regions, especially on Oahu. Several of the genera 

 which occur in the littoral zone are also to be found here as well 

 as are some which are typically of the forest zone which gen- 

 erally extends down the moist gulches and valleys. Some typical 

 genera of this zone are: Gleichenia, Sphenomeris, Sadleria, 

 Cordyline, Dracaena, Pipturus, Osteomeles, Acacia, Leucaena, 

 Erythrina, Pelea, Aleurites, Dodonaea, Sapindus, Sida, Wal- 

 theria, Wikstroemia, Styphelia, Osmanthus, Clermontia, Scae- 

 vola, and Heteropogon. 



The forest extends from the upper edge of the lowland zone 

 to about 10,000 feet. Three zones are recognized each with more 

 or less distinctive species, yet showing considerable overlapping: 

 a lower more or less open forest with Gleichenia, Cibotium, 

 Freycinetia, Zingiber, Pipturus, Pittosporum, Aleurites, Ilex, 

 Elaeocarpus, Xylosma, Eugenia, Metrosideros, Cheirodendron 

 Maba, Osmanthus, Alyxia, Gouldia, Straussia, and Scaevola 

 as common genera; a middle zone including Gleichenia, Dryop- 

 teris, Cibotium, Pritchardia, Peperomia, Broussaisia, Euphor- 

 bia, Viola, Eugenia, Metrosideros, Cheirodendron, Labordea, 

 Suttonia, Phyllostegia, Gardenia, Gouldia, Kadua, Nertera, 

 Lobelia, Scaevola, and Dubautia as representative genera; and 

 the upper forest zone extending to the upper limits of the high- 

 est mountains includes Acacia, Wikstroemia, Vaccinium, Copro- 

 soma and Argyroxyphium. 



Some of the most interesting regions are the so-called alpine 

 bogs which occur between 4000 and 6000 feet altitude in a few 

 places in the islands. The largest ones are on Kauai near Mt. 

 Waialeale and on Puu Kukui and Mt. Eeke on west Maui. The 

 bogs are open with scattered islands or intrusions of dwarfed 

 trees and shrubs and covered with tussock-forming species of 

 grasses and sedges. Oreobolus furcatus, Panicum imbricatum and 



