FIELD CROPS. 948 



tables. Tlie nitrogen content in the dry matter varied from 0.8 to 1.41 per cent, 

 with an average of 1.02 per cent, the stems? containing 0.24 per cent, the kernels 0.78 

 per cent. Unripe samples showed a high percentage of nitrogen in the stems and a 

 low percentage in the grains. The tigures representing the nitrogen content of the 

 hulls and kernels, the stems, and the leaves, 1)ear no definite relation to each other, 

 while the nitrogen content of the kernels and the hulls and kernels, owing to the 

 low nitrogen content of the hulls, varied in about the same ratio. Plants grown in 

 jiots h\ connection with these experiments contained a higher percentage of nitrogen 

 than the field samples, but in the greater number of samples in both cases the nitro- 

 gen content in the kernels ranged from 1.30 to 1.69 per cent. A high nitrogen con- 

 terit in the green plants was indicative of a high percentage of nitrogen in the ripe 

 kernels. The average for the ripe kernels was 1.64 per cent and for the green plants 

 1.20 per cent. 



The greater portion of the phosphoric acid was found in the grains. The 

 leaves had a higher percentage of phosphoric acid than the stems, but the absolute 

 amount was smaller. The ripe hulls contained a very small quantity of this element. 

 The average quantity of phosphoric acid in the dry matter was 0.427 per cent, 0.094 

 per cent being in the stems and 0.333 per cent in the grains. This shows that the 

 variations are relatively much greater than the variations in the nitrogen content. 

 The average content of phosphoric acid of the stems and the grains showed some 

 relation to each other, although in general it was not very definite, while in the 

 stems and leaves the relation was definitely shown. A content of more than 0.30 

 per cent in the stems was found only in those plants which showed a high content 

 in the grains. All samples with a high content of phosphoric acid had been grown 

 on soils rich m hme and liberally supplied with phosphoric acid. Plants grown in 

 the culture pots showed a higher percentage than the field samples. In the pot- 

 grown samples the pliosphoric acid content in the green plants increased regularly 

 with the percentage in the ripe grains, but when the content in the grains had 

 reached 0.90 to 0.95 per cent it remained practically constant. 



The greatest variations in the content of potash occurred in the stems. When the 

 jilants contained a high percentage of potash the larger portion was found in the 

 stems, and when the quantity was low in the plants the stems and the leaves held 

 about equal amounts. The lowest potash content was found in samples from moor 

 soils and the highest in samples from clay soils and moor soils well fertilized with 

 potash. The potash figures of the grains remained almost constant and bore no 

 relation to the figures representing other jiarts of the plants. Fluctuations in potash 

 content of the leaves and the grains were small. The average content of potash in 

 the dry matter was 1.05 percent, the stems showing 0.76 per cent and the grains 

 0.29 per cent. Plants grown in pots produced grains of a higher potash content than 

 the field-grown plants. This was found to be true only in the case of potash. ( treen 

 and ripe stems showed equal fluctuations. 



The largest variations in the lime content occurred in the leaves, while in the grain 

 only a small variation was noticed. All sam{)les from soils rich in carbonate of lime 

 contained over 0.35 per cent of lime in the stems. The average lime content in the 

 ilry matter of the plant was 0.256 per cent, the stems containing 0.1 9S per cent and 

 the grains 0.058 per cent. The stems and leaves contained e(iual (juantities. The 

 lime content of the stems and leaves of the plants grown in pots was almost 100 per 

 cent greater than in the stems and leaves of the plants grown in the field, (ireen 

 samples fluctuated as widely as ripe ones, but the average content of the ripe stems 

 and leaves was 0.10 per cent higher. Among the field samples those from limy soils 

 contained 0.60 to 0.75 per cent of lime in the stems and leaves while the .samples 

 from moor soils poor in lime contained only Irom 0.17 to 0.20 percent. iSeveral 

 samples from sandv soils showe<' a Jime content of from 0.50 to 0.60 per cent. 



The largest aVjsolute quantity of magnesia was contained in the grains and the 



