MANURING EXPERIMENTS WITH PADDY RICE. 
35 
The rate of potash consumed from the manure nearly comes 
up to the high proportion of nitrogen assimilated from am¬ 
moniacal fertilizers. If moderate doses of potash are applied, 
the rice plants take up nearly half of them. From excessively 
large dressings less (only 40%) is consumed. 
The preceding researches still furnish valuable information 
as to the stock of nutrients available to the rice crop in our 
soil. We found in the crop produced with a sufficient supply 
of phosphoric acid and potash, but without any nitrogen in 
the manure, a quantity of nitrogen amounting to 8.542 grms. 
The little plants raised in the seed beds and used in the 
experiments contained, according to an analysis : 
In 1000 
Per frame. 
individual plants 
240 plants. 
Dry matter 
85.63 grms 
20.55 grms. 
Nitrogen . 
... 1.527 „ 
0.366 ,, 
Phosphoric acid 
... 0.362 „ 
CO 
O 
Ö 
Potash . 
... 0.770 „ 
0.192 „ 
Lime. 
... 0.177 » 
0.043 „ 
Upon deducting 0.366 grms. of nitrogen from the quantity 
obtained in the mature crop, we get 7.176 grms., which must 
have been taken up from the stock in the soil. Assuming this 
nitrogen to have been consumed in the torm of ammonia and 
taking into account that from the ammoniacal compounds in 
the soil rice plants can absorb, according to our results (p. 28), 
62.2%, we come to the conclusion that our soil contained per 
plot 11.54 grms. of nitrogen equivalent in efficacy to ammonia¬ 
cal nitrogen. This makes per tan 12.57 kilogrins, of available 
nitrogen. 
As to phosphoric acid , the crops harvested without any sup¬ 
ply of this nutrient from the unmanured plots and from those 
manured with copious quantities of nitrogen and potash, con¬ 
tained in the average per plot 0.605 grms. As in the 240 
