146 • BOTANICAL GAZETTE [august 



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Of particular interest, from the ecological viewpoint, are the 

 root systems of the tapestry grove trees and shrubs. The combi- 

 nation of steep declivity, thin clay soil, and rock substratum 

 necessitates the development of an unusually strong mechanical 

 root-supporting system. Most of the trees have a number (5-12) 

 of large proplike roots which extend downward below the trees, 1 



and are firmly rooted in interstices in the ancient lava beds. These 

 lower roots brace the tree staunchly from below. On the upper ! 



side of the trunk are usually several long anchoring roots, more or 

 less exposed in the thin vegetable mold. The extremities of these 

 roots are likewise rooted among the rock strata. In some situa- 

 tions, where the processes of erosion are gaining upon the grove, 

 and have washed away much of the grove floor, the intricate sys- 

 tems of anchoring and bracing roots are beautifully displayed. 

 On many cliffs and steep ridges these strong roots form a sort of N 



natural ladder, well known to the natives and woodsmen, who 

 utilize them in ascending or descending the slopes. In many 



situations ascent would be well-nigh impossible were it not for 

 these tough, firmly anchored, exposed roots. 



Lianas of various species establish themselves in the tapestry 

 groves, and in some places become so luxuriant as to form almost 

 impenetrable hanging jungles. Conspicuous among these vines 

 are species of Freycinetia, Dicranopteris, Smilax, Dioscorea, Alyxia, 

 Ipomoea, Convolvulus, etc. The liana formations are best devel- 

 oped at the lower levels; above 2000 ft. the groves are practically 

 free from vines, which are replaced by the dense soggy moss 

 formations. 



The tapestry groves, owing to the hygrophytic environment, are 

 usually heavily clad with thick layers of epiphytic lichens, mosses, 

 filmy ferns, and liverworts. These layers, on the smaller branches 

 and saplings, are often 4-8 inches in radius. The outer layer 

 alone is green and living; the under layers, of dead vegetable 

 material, are saturated with rain water, and may be wrung out 

 like a wet sponge. This moss covering is best developed at the 

 higher altitudes (1800-4000 ft.), where the annual precipitation is 

 100-400 inches. These upper tapestry groves are swathed in fog 

 and rain during most of the year, and comprise a range of woody 

 species different from that of the lower groves. 



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