36 
had the effect of increasing the percentage of total ash in the plant, 
of increasing the lime, and of diminishing the nitrogen. Between 
the chlorotic and green plants there were no regular differences in 
the percentages of phosphoric acid, iron, and magnesia in the dried 
substance. 
From a consideration of these analyses alone it appears, by a 
process of elimination, that the chlorosis is in some way dependent 
upon the content of lime or iron in the ash or upon the content of 
ash, lime, or nitrogen in the dried substance. j 
In fields of chlorotic plants growing on calcareous soils there were 
always certain individual plants that maintained a green color longer 
than the others. These plants eventually became chlorotic, but it 
was thought that possibly the ash content of the plants, which had 
not yet become chlorotic, might show some regular differences from 
the ash of plants that were already chlorotic. In the table below 
such comparative analyses are given. The first four analyses are 
of plants grown on a soil containing 3.30 per cent of calcium carbon- 
ate. The next two analyses are of plants grown on a soil containing 
79 per cent of CaCO,, and the last two of plants grown on a soil 
containing 33 per cent of CaCO,. The analyses are to be compared 
by twos, as in each case the chlorotic plant and check plant were 
grown under the same conditions. 
Analyses of the ash of chlorotic and green plants from calcareous soils. 



















Analysis of carbon-free ash. Ash Ge neaecd pabsbaties 
2 
Descripticn | Appearance ais QA) 4 = |2 Se Raed 3 |A 
of plant. of leaves. E 2 mee Fe no, g & 3 | eae $ sae 
a a a = Gl 32 -_ 
2 | S | aS lee} So] & |sd| S |aS) ee | So] & | og 
2 | 8 |sdles| 4] 3 |g | 8 jed/ge/ oH) s |= 
A | Ala [8] a AE Sve Sy i Seep Pep ee 
P.ct.| P.ct.\P.ct.| P.ct.|P.ct.|P.ct.\P.ct.|P.ct.|\P.ct.\P.ct.|P.ct.\P. ct. 
Large Cabezo- | Green......- 237 | 27.33} 9.12) 5.89) 33.44) 1.11) 6.00) 1.64) 0.55) 0.35) 2.01) 0.07} 0.90 
na, 18 mos. 
old 
BOie ee oce Chlorotic....| 238 | 26.18} 14.19] 8.53)......]..... ee 34a ae 1 dew (3 Vike 3] a Lee “ffl 
Small Cabezo- | Green....... 233a| 23.16] 6.70) 8.54) 43.72) .49) 5.81) 1.35) .39) .50| 2.54) .03) .76 
na, 18 mos. 
old. 
Dont ee Chlorotic....| 233d} 24.00] 10.35} 5.66) 29.65} .47] 7.70} 1.85) .80| .44/ 2.28) .04| .76 
Red Spanish, | Green......- 196 | 29.40} 12.55] 4.42) 13.05)..... 6. 28] 1.85} .79} .28] .82)..... 91 
24 mos. old. 
Dow s255 Chlorotic....) 195 | 29.45] 9.83] 3.45) 19. 78]..... 7520) 209) ow Olp peo] kcal ones . 66 
Red Spanish, | Green......- 1049) Daesw|e soso 4.93) 35.45) . 43) 6.56) 1.53)..... .32| 2.33) .03] 1.47 
14 mos. old. 
DOsse neo Chiorotic:. |) 103: || 28.17|-- 22.2 3. 46] 33.64] .55) 7.81) 2.20)..... .27| 2.63} .04| .88 




It will be seen from the table that there are no differences between 
the analyses of the green and chlorotic plants that are sustained in 
allfour cases. The nitrogen content of the green and chlorotic plants 
is in one case equal but in the other three cases in this table, as well 
as in all the other analyses made, the chlorotic plants contain much 
less nitrogen than the corresponding green plants. 
[Bull. 11] 

