8 T. L. Lyon anp J. K. Wixtson 
barley, peas, potatoes, and mustard. The plants were harvested at | 
different stages of growth. These plants were carefully divided into | 
their component parts — roots, stems, ears, and so on — and were dried, | 
weighed, and analyzed. The results as stated below are based on pounds — 
of nitrogen in the crop. | 
The barley was planted on March, 30 and the cuttings were made on _ 
May 29, June 17, July 3, and July 27. The plant parts were separated _ 
and grouped into aboveground parts and underground parts. Separate | 
analyses were made of stems, green leaves, yellow leaves, ear stalks, awns, | 
straw, grain, roots, and stubble. Total weights of nitrogen showed that 
this nutrient was present in its greatest amount on June 17 (presumably 
when the plants were in bloom) and that the mature cutting of July za | 
had lost 25 per cent of the total nitrogen. 
The wheat was planted on April 23 and was harvested on June 22, | 
July 14, August 5, and August 28. The methods used were the same as | 
for barley. In the case of the wheat, the nitrogen was found in its greatest, | 
amount in the third cutting, on August 5, and the mature crop showed a | 
loss of about 20 per cent of the total nitrogen. 
The potatoes were planted on April 28 and analyses were made of the | 
various parts of the plant. Four different harvests were gathered as the | 
crop was maturing. The results were quite different from those with — 
barley or with wheat. In this case the greatest amount of nitrogen was © 
found in the last harvest, which represents the crop gathered in October. 
The barley was planted on April 20 in sand in pots, and was watered | 
with nutrient solutions. Quadruplicate cultures were grown in the green- 
house. On May 11 stems had commenced to show. The first harvest 
was made on May 24, the second on June 1, the third on June 12, the 
fourth on June 25, the fifth on July 20. The harvest consisted of both | 
roots and tops. In one series the greatest weight of nitrogen was found 
on June 25, in the other three on June 12. From these dates on to maturity 
there was a loss of total nitrogen ranging from 9 to 26 per cent. | 
The peas were planted and tended in a similar manner to the barley, 
with the same dates for planting and harvesting. The weight of nitrogen’ 
in the harvested crops was greatest on June 25 in three cases, and in the: 
fourth case at the last harvest. The decrease toward maturity in the 
three cases ranged from 9 to 30 per cent. 
