THE VARIOUS FOREST REGIONS ON THE ISLAND 



OF HAWAII 



The Island of Hawaii is composed mainly of the three mountains, Mauna 

 Kea (13,823 feet), Mauna Loa (13,675 feet), and Hualalai (8273 feet), while 

 the western end, the mountains of Kohala, are said to have formed once a sepa- 

 rate island, being about of the same age as West Maui. The now extinct volcano, 

 Mauna Kea, the highest mountain of the Pacific, is the oldest volcano on Hawaii, 

 while Mauna Loa, whose summit crater, Mokuaweoweo, still becomes periodically 

 active, is the youngest. Mt. Hualalai, the lowest of the volcanoes on Hawaii, now 

 supposed to be extinct, was last active a little over a century ago, its last erup- 

 tion, in 1801, being thought to have been witnessed by an Englishman. 



Naturally an island like Hawaii, still in process of formation, represents 

 widely ranging districts : ancient lava flo\vs, deserts, dense tropical rain forests, 

 dry or mixed forests, new lava flows bare of any vegetation, alpine zones, and 

 almost any climate from dry desert heat to the most humid air of the rain forest, 

 from tropical heat to ice and almost perpetual snow at the summits of the moun- 

 tains, where a temperature of 13 degrees Fahrenheit in midsummer is nothing 

 uncommon. From a phytogeographic standpoint the island of Hawaii offers the 

 most interesting field in the Pacific. 



All these various districts, with their peculiar climates, support many inter- 

 esting types of plant coverings. 



The windward side of Hawaii, as of nearly all the other islands, is very pre- 

 cipitous, especially along the western end, the Kohala mountains, where ver- 

 tical cliffs nearly 3000 feet in height are covered with verdure almost to the 

 the water's edge. The rainfall is exceedingly heavy in this district, and the 

 waters have cut huge gorges into these rocky walls, such as the valleys of Waipio, 

 Waimanu, Pololu, Honokaneiki, etc. The vegetation of these valleys is rather 

 uniform, and has been described under the lower windward forest region. 



Between Kohala and Mauna Kea is a large plain of many thousands of acres, 

 now mainly grassland, at an elevation of 2000 to 3700 feet, after which the slopes 

 of Mauna Kea rise more steeply. At from 3700 feet up to 7000 feet, on this big 

 plain, is a belt of forest composed mainly of Sopliora clirysopliylla, while lower 

 down are scattered trees, usually Osmantkus sandwicensis, the Hawaiian olive, 

 with Myoporum sandwlcense, the Naio, etc. To windward, the mountain slopes 

 rather gently, forming the Hamakua coast, which at the lowlands has been 

 planted with sugar cane exclusively up to an elevation of 2000 feet. From thence 



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