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cate that rock phosphate, when acted upon for a few months by 
decaying organic matter, becomes as available as superphosphate, 
but when applied without organic matter the immediate e fleet is 
negligible. From these experiments it also seems that water-soluble 
phosphates produce better immediate effects than reverted phosphate 
and bone meal. It has also been found that the availability of the 
phosphate already in the soil can be considerably increased by plow- 
ing under green manure, and that liming in some instances is neces- 
sary before phosphate fertilizer will give its best effects. Hawaiian 
soils have the power of fixing very large amounts of phosphoric acid, 
and, therefore, loss will not be sustained by leaching. It seems, how- 
ever, that where excessive amounts have been applied some of the 
phosphoric acid becomes reverted into unavailable forms. 
When potash fertilizer is needed the sulphate is recommended, and 
potash, like ammonia, is not lost by leaching if applied in reasonable 
amounts. 
CHEMICAL AND MECHANICAL COMPOSITION OF SOME HAWAIIAN 
SOILS. 
In the following tables are given the results of chemical and mechani- 
cal analyses of a large number of soils and subsoils taken from differ- 
ent parts of all of the principal islands. In Table I the results of the 
chemical analyses of soils and subsoils 1 are given; in Table II the 
humus, humus ash, and total nitrogen are stated; and in Table III 
the mechanical composition is shown. In general the soil represents 
the first foot and the subsoil the second foot taken. In most instances 
the material analyzed represents a composite of from two to five 
samples taken in the same locality. The methods employed for the 
chemical analysis were those of the official agricultural chemists. 
The classification of soils adopted in the table of mechanical composi- 
tion is that of Hall. 2 
1 The subsoil in all cases was taken in connection with the preceding soil sample. 
2 The Soil. London, 1908, 2. ed., p. 51. 
