10 T. L. Lyon anv J. K. Witson 
potato plants at various stages of development was 69 pounds at the 
first harvest (thirty-three days), 241.3 pounds at the second harvest 
(fifty-eight days), 306.7 pounds at the third harvest (eighty-nine days), 
and 319 pounds at the fourth harvest (one hundred and twenty-four 
days). There was a constant assimilation of this important element. 
Hay was cut by Crowther and Ruston (1911-12) from uniform areas 
of a crop of grass which had been seeded the previous spring. The grass 
seed consisted of a mixture of perennial rye grass, Italian rye grass, 
white clover, trefoil, alsike, English single-cut cow grass, Chilean red 
clover, and rib grass. The first cutting was made when the rye grass 
was in full flower. A good growth of leguminous plants showed under-. 
neath. The second cutting was made when the rye grass was forming | 
seed and the clovers were beginning to flower. At the third cutting the | 
grasses were ripening and the clovers were in full bloom, while the fourth | 
and last cutting was made when the crop was decidedly ripe. Analysis | 
of the crops showed the greatest total weight of nitrogen to be present, at 
the third cutting, or when the grasses were ripening and the clovers were | 
in full bloom. In the last cutting there was a loss of 25 pounds of nitrogen | 
to the acre. 
The work was repeated the following year, but with barley as the crop. 
The seed was drilled on May 12. Cuttings were made on June 9, June 23, | 
July 7, and July 21, but the stages of growth reached on these dates were 
not noted. The changes with advancing age as to nitrogen were similar 
to those observed in the preceding year with grasses. 
The changes in chemical composition of the timothy plant during 
growth and ripening, with comparative studies of the wheat plant, are. 
recorded by Trowbridge, Haigh, and Moulton (1915). Timothy plants, 
cut from uniform areas, represented the following stages of growth: (1) 
about one foot high in rapid growth; (2) no heads showing; (3) no stalks! 
in bloom but beginning to head; (4) in full bloom; (5) just out of bloom 
and seed formed; (6) seed in dough; (7) seed fully ripe; (8) growth the 
following spring not yet started but leaves green. The plant parts of 
the samples thus collected were divided into heads, stalks and leaves, 
hay, and stubble and bulbs. The amounts of the various nutrients deter- 
mined were recorded in total pounds to the acre. Data from these plants 
were collected for one year only. The figures for weight of nitrogen 
showed that there was a gradual increase in this constituent in heads from 
