-6 7 
Silicic acid. 
Phosphoric acid. 
Sulphuric acid. 
Chlorine. 
Lime. 
Magnesia. 
Oxide of iron. 
Alumina.. 
Brown oxide of manganese 
Potash. 
Soda. 
ho nitrogen in the hay amounts to 200.79 pounds. 
1 he amount of plant food in the soil, however, is so larcre 
that it is scarcely possible but that a very large excess over 
that required by the crop was obtainable at all times 
throughout the season. The total plant food present in the 
soil penetrated by the roots in this case is so large that it 
seems to have no object in trying to express the quantity in 
figures. 1 he quantity of phosphoric acid present in one 
acre of this soil and its subsoils taken to the depth of 
eleven and one-quarter feet is approximately thirty-four 
and one-quarter tons, and about three times as much 
potash, or one hundred and two tons. It would seem proba¬ 
ble that,under these conditions, the plant would contain as 
large a quantity of ash ingredients as it could take up,but the 
average ash content of alfalfa hay,including all cuttings and 
varieties of alfalfa grown in Europe and different parts of 
this country, is 7.44 per cent., or nearly as«great as the aver¬ 
age of the samples collected by ourselves, including this 
particular one, 9.08 per cent., for the first cutting^ and 
rather higher for the second and third cuttings. Our aver¬ 
ages are something higher than that given by Mayer and 
others. This difference is reduced a little when the lower 
vvater content of our hay is taken into consideration; but 
there still remains an excess over the average ash content. 
I his may correspond to the amount which is taken from 
our soils in excess of the normal amount due to an ex¬ 
cessive supply. It is to be remembered that the alfalfa in 
our case is practically growing in a virgin soil, even if the 
upper soil has previously been sown to wheat, for the wheat 
roots, whatever depth they may attain in loose open soils, 
Pounds. 
. I 3 . 4 I 
• 39-«7 
• 50-31 
. 71.28 
212.85 
• 53-01 
. - 3.60 
• 2.25 
.. 1.71 
213.21 
. 16.38 
677.88 
