10 
This is a coralline sand, evidently formed by the sea grinding down 
coral reefs. It will be seen that although it is fairly rich in nitrogen, 
potash, and phosphoric acid it is excessively calcareous, like the bad 
soils in Survey I. The trouble here, however, was complicated by 
poor drainage. 
SOIL SURVEY III. 
Plantation of Mr. Mathews at Rincon, P. R.: This is the plantation 
described on page 5. In 1910 the field was visited by the writer. 
The plants had been removed some years previous, but a few plants 
were found which were of fair size, although practically colorless. <A 
soil sample, No. 224, was taken near these plants. 
In the vicinity 6 or 7 plants of the native variety Caraquefia were 
found growing. Two of these plants were very small and almost 
pure white; the others were of fair size with very light green narrow 
leaves. The soil sample from near the roots of these plants is No. 225. 
A quarter of a mile farther on a small patch of about a hundred 
Cabezonas and Caraquefias were found growing. All the plants 
were of small size and light-greenish yellow or yellow-white in color, 
A few plants were bearing dwarfed fruits. The soil from this spot 
is designated as No. 226. The soil in these three cases was of the 
same character, a coarse, well-drained, beach sand with a fair amount 
of organic matter. Coconuts, oranges, and gandules or pigeon peas 
seemed to grow well here. 
Analyses of pineapple soils (plants chlorotic). 






Soil constituents and reaction. No. 224. No. 225, No. 226. 
Per cent. Per cent. Per cent. 
Insoluble matter 70.15 67. 63 75. 36 
Potash. (K50) 2s. ...5-.-- cep ag . 09 . 09 - 09 
nme (CaO) ons asses bed eos oe a 11.77 12. 40 8. 28 
Magnesia (MgO) mS - 36 1.07 5. 20 
Ferric and aluminic oxids (FegO3 and AlgO3) ............-...------- 4.06 4. 52 5. 20 
Phosphorus pentoxid (P3005) 22/22 eens 22 220s eee es wie eae Be eee - 09 .16 -12 
VMolatilomatter a. 352225 <i: cetees.ce an doneneoe bes eater Ree aerate 12. 95 13. 29 10. 80 
Total: os wu chee oh Ae En ie es Re oie Sa ee 99. 47 99.16 100. 12 
INitromem(N) 2.6 Ses atelier Oe ne me ee eee 09 .10 16 
MOIStUIG. - o.2-n0~ ons hdc octeie ces SRE Dae ge sk noe ae rete eee Se . 69 . 76 1.00 
Carbon: diexid:(COs) 2:1) ic. sarees 2 ee: eee 7.93 9. 57 6. 29 
Caleiumicarbonste (Ca®Os)-: ns one Aecioce cea eee ee 18. 04 PAL Ws 14. 31 
Reaction toillitmmus: = e.. =. o Siena sees Sa cues Rees eee eee Alkaline. | Alkaline. Alkaline. 


These soils are slightly richer in potash and phosphoric acid than 
in Survey I and not so- high in lime, but they are still to be regarded 
as strongly calcareous. 
SOIL SURVEY IV. 
Property of Mr. William Gay, Dorado, P. R.: Here about 2 acres 
of red Spanish pineapples were set out on asand near the sea. The 
soil was of good physical character with considerable organic matter, 
[Bull. 11] 
