MILPA AGRICULTURE — COOK. 311 
pasture to be found for the saddle and pack animals. Fires are seen 
continually burning day and night all over the mountains up to the 
highest crest, leaving the stony ground blackened and barren, but the 
forests stand green." 
With fires sweeping over the country at intervals of a year or two, 
the grasslands not only are maintained but may even encroach upon 
adjacent tracts of woody vegetation from the windward side. The 
wider the area of grasslands the more they tend to increase through 
the agency of fire, until the whole district is denuded, or forests re- 
main only in places that are inaccessible to fire because grass does 
not grow, as on rocks, loose sand, or flooded areas along the streams. 
When the process of denudation has gone so far that land for milpas 
can no longer be cleared and planted by the native methods the 
period of agricultural occupation is at an end. Thus the milpa sys- 
tem carries with it the agency of its own destruction in producing the 
grasslands that are not amenable to the kind of cultivation that the 
system j^rovides, and the process tends to accelerate as the limit is 
approached. As long as a district is occupied by an agricultural 
population using the milpa system the danger of fire remains. 
The regular use of grasslands for agricultural purposes is confined 
to temperate regions and to high altitudes in the Tropics. Plowing or 
some equivalent operation must be performed in order to uproot, 
l)ury, or otherwise destroy the grasses before crops can be planted. 
But plows and harrows are worked with draft animals, which primi- 
tive tribes do not have. 
Grasslands are subdued by hand labor in a few overpopulated 
tropical regions. A nearly continuous cultivation is maintained in 
some of the mountain districts of Haiti where grass and weeds are 
dug out with cutlasses. The result is a more rapid and complete 
denudation of the land, and a restricted production of food must be 
expected if better systems are not introduced. Another result is 
heavier floods and land slides that destroy agricultural lands in the 
lower valleys. (PL 13, fig. 2.) 
A more primitive and yet distinctly specialized system of cultiva- 
tion of grasslands is reported by Chalmers and Gill among the 
natives of southeastern New Guinea. 
The plantations are well cared for. We came upon a number of men in the 
bush preparing the soil for planting. The long grass had been burnt off. Now, 
for the digging up of the hard ground. Several men stood in a row, each pro- 
vided with a sharp-pointed strong stake. These are driven into the soil in 
unison ; in another second the hard clods are flj'ing upward all along the line, 
reminding one of the perfect regularity with which a man-of-war's crew dig 
into the water. These men went on with their employment without paying the 
slightest heed to us strangers.* 
* Chalmers, J., and Gill, W. W., 1885, Work and Adventure in New Guinea, p. 295. 
