This is the limit of tree growth. Above this, old and more recent lava flows 
cover the ground, which is either bare or covered with a scrubby vegetation such 
as just described. 
VEGETATION OF THE LAVA FLOWS OF KAU AND SOUTH KONA FROM SEA LEVEL TO AN 
ELEVATION OF 4200 FEET. 
Between Waiohinu and Kahuku the vegetation is mainly composed of Oh ia, 
with an occasional sandalwood tree, Santalum Freycinetianum var. latifolium. 
Lava flows of various ages have descended from the upper as well as the lower 
slopes of Mauna Loa, some having reached the sea, others having just crossed 
the government road (1200 feet), while minor flows have descended for only 
about a mile from their source, after which they cooled and stopped. The 
neighborhood of Kahuku is the seat of many eruptions, some within the memory 
of man, as two flows came forth from the southern slopes of Mauna Loa, one in 
1867, and another in 1887, while as recently as January 9, 1907, after a few 
slight earthquakes, another flow proceeded in the same direction from an eleva- 
tion higher than that of the two previous flows. This last eruption emerged con- 
siderably below the summit of Mauna Loa, pouring forth a stream of aa (rough 
lava) which divided into two nearly equal streams, with a smaller one between 
This is, however, not the place to give a description of the behavior of lava flows, 
and the writer wishes to refer the reader to Dr. Wm. T. Brigham’s valuable 
publication on the Voleanoes of Kilauea and Mauna Loa. All three flows men- 
tioned above are entirely bare of vegetation, and the half century intervening 
has not changed the appearance of these various flows in the slightest. The 
older ones look exactly as does the one of 1907, the only difference being in the 
color, which is a trifle lighter shade of brown. It is most interesting to note 
little areas of more ancient flows, perhaps only an acre or smaller in extent, 
which have not been covered by these fiows, and bear an occasional shrub of 
Nototrichium, with Sadleria ferns, or a small, stunted Ohia. These more recent 
flows are very irregular in outline, and in the actual flow little islands of many 
shapes have remained—that is, islands of old lava beds, bearing a typical dry 
scrub vegetation which was spared by the fiery streams. The last flow at first 
came forth as pahoehoe (smooth lava), while lower down it assumed aa form, as 
can be seen along the government road. 
The first plant to settle along the margins of these various flows is Nephro- 
lepis exaltata, a cosmopolitan fern. Sadleria ferns follow after it or perhaps 
at the same time, but the former was always to be observed when hardly a grass 
or weed of any kind was visible. Two branches of the recent 1907 flow are about 
four miles apart, and this stretch of land is covered by a dry serub vegetation 
and occasional trees, such as Xylosma Hillebrandii (Maua), which is by far 
the most common tree next to Ohia, Antidesma pulvinatum (Hame or Haa), 
Pipturus (Mamake) and Sadleria ferns. The land of Kahua, which is appar- 
ently older than Manuka, is of a rough lava nature, with occasional kipukas, and 
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