Apr. y. T<>23 Nutrition of Plants as an Electrical Phenomenon 
43 
is stored up in the seed, and which is fairly evenly distributed through 
it, begins to move very rapidly toward the end containing the germ or 
embryo. In the germination, when the embryo has broken through the 
bran coating and is just large enough to get hold of with the thumb 
and finger nails, it contains about 50 per cent of the total potash of the 
seed. The seed does not contain enough potash to satisfy the demand 
of the little seedling, so it begins early to feed heavily on the nutrient 
of the solution. Probably, in the natural course of life, the very first 
food absorbed by the little seedling is potassium. The absorption of 
nitrogen is steady and comparatively uniform, so after 18 or 20 days 
the curves for potash and nitrogen cross each other. The absorption of 
phosphoric acid is regular also. 
Without submitting all the data, the curves for a duplicate determina¬ 
tion, made about one month later, are given in order to bring out the 
crossing of the curves of nitrogen and potash (fig. 2). 
The data presented give an idea of the nutrition of a plant when 
feeding full time and under favorable conditions. But a plant in nature 
does not necessarily have ideal conditions in which to grow. A low 
moisture content of the soil may temporarily put a stop to nutrition or 
the fluctuation of plant food, particularly nitrates, in the soil solution 
may also slow down, or even stop, absorption. It is, therefore, important 
to know what percentage of the time is actually necessary for absorption 
and whether a plant can absorb enough plant food in one period of time 
to last it over another. 
