THE ASH OF PLANTS. 157 



The composition of the ash of a number of ordinary- 

 crops is concisely exhibited in the subjoined general 

 statement. 



Cereals — 



Grain*,... 80 12 3 4G 2 2.5 1 



Straw 13—37 3 7 5 BO-70 2.5 2 



Legume a — 



Kernel.... 44 7 5 38 1 4 2 



Straw 27-^1 7 25—39 8 5 2—6 6—7 



Root Crops — 



Eoots 60 3—9 6—12 &-18 1-4 5—13 3-9 



Tops 37 3—16 10—35 3—8 3 6—13 6—17 



Grasses — 



In flower.. 33 4 8 8 35 4 5 



3. Different parts of any plant usually exhibit decided 

 differences in the composition of their ash. This fact is 

 made evident by a comparison of the figures of the table 

 above, and is more fully illustrated by the following anal- 

 yses of the parts of the mature oat-plant, by Arendt, 1 to 6, 

 {Die IIaferpflanze,p. 107,) and Norton, 7 to 9, (Am. Jour. 

 Sci., 2 Ser. 3, 318.) 



123456789 

 lower Middle Upper Lower TTpper Ears. Chaff. Uusk.Kemel 

 Stem. Stem. Stem. Leaves. Leaves. huslced. 



Potash 81.2 68.3 55.9 36.9 24.8 13.0 I in o ia a oi .r 



Soda 0.4 1.5 1.0 0.9 0.4 0.1 r"-° ^^'^ ^^'^ 



Magnesia 2.1 3.6 3.9 3.8 3.9 8.9 1 3.3 8.6 



Lime 3.0 5.3 8.6 16.7 17.2 7.3 \_„ „ 4.3 5.3 



Oxide of Iron 1.0 0.0 0.2 2.7 0.5 trace ("■'' 0.3 0.8 



Phosplioric acid 2.7 1.4 2.7 1.7 1.5 36.5 J 0.6 49 1 



Snlphuricacid 0.0 1.3 1.1 3.2 7.5 4.9 5.3 4.3 0.0 



Silica 4.1 9.3 20.4 34.0 41.8 26.0 68.0 74.1 1.8 



Chlorine 8.6 11.7 7.4 1.6 2.4 3.8 3.1 1.4 O.ft. 



The, results of Arendt and Norton are not in all respects strictly com- 

 parable, having been obtained by different methods, but serve well to 

 establish the fact in question. 



We see from the above figures that the ash of the lower 

 stem consists chiefly of potash, (81 °|„.) This alkali is pre- 

 dominant throughout the stem, but in the nj^ijer parts, 

 where the stem is not covered by the leaf sheaths, silica 

 and lime occur in large quantity. In the ash of the leaves, 



* Exclusive of husk. 



Digitized by Microsoft® 



