300 BULLETIN OF THE BUSSEY INSTITUTION. 
advantage gained by the plants from the nitrogen naturally con- 
tained in the loams and peats. This point has been discussed at 
some length in a special article in the first volume of the Bulletin 
(see page 252). Indeed in the experiments with loam alone the 
crops from jars numbered 6, watered with nitrate of ammonia, 
seemed to show that there was little if any need of adding a nitro- 
genous fertilizer; and some of the crops (Nos. 1 and 3, loam 
alone) watered with the nitrates of potash and lime tended to cor- 
roborate this view, when put in comparison with crops which had 
received no nitrate. It seemed plain that no methodical results 
could be hoped for until the soil-nitrogen had been got rid of. 
Even in the experiments with the mixtures of loam and sand, 
where the soil-nitrogen was of course greatly diluted, it frequently 
appears as if no nitrogenous fertilizer were needed, beside that 
natural to the loam. Compare, for example, the experiments 
with Plain-field loam. 
The experiments seem to show that Mr. Appleton’s loam needs 
phosphoric acid and does not need potash, and that Mr. Salton- 
stall’s loam does not need phosphoric acid, though it may need 
potash somewhat. As regards the Plain-field loam, the results are 
somewhat conflicting; this loam responds freely to mixtures of 
phosphoric acid, potash and nitrogen, though not to potash alone 
in the manner that was to have been expected from its behavior 
in the field.* It seemed to need phosphoric acid less than Mr. 
Appleton’s loam. 
In respect to the experiments with peat, it is remarkable that in 
several instances the plants were able to procure from the peat it- 
self not only nitrogen, but enough phosphoric acid and potash to— 
bring fair crops to maturity, though the addition of active nitrogen 
did good both by itself and when mixed with potassic and phos- 
phatic fertilizers. In jar No. 5, Bussey peat which was watered 
with nitrate of ammonia, the question suggests itself whether 
ammonium may not possibly have fulfilled some function ordinari- 
ly fulfilled by potassium. The case is somewhat different from 
that of the mixture of Plain-field earth and sand Jar No. 2, which 
was watered with a mixture of nitrate of ammonia and phosphate 
of ammonia, for in this instance the ammonia compound may have 
liberated potash from the soil which, as compared with the peat, 
contained a considerable store of it. 
In the Bussey peat the crops grew well and the experiment was 
* Compare Bussey Bulletin, vol. 1., the several records of field experiments. 
