SOILS. 631 



"The moro polnble forms of magnesia, as nitrate and sulphate, are in excess more 

 injurions to plants than the less solnble, as carbonate, while the more solnble forms 

 of lime, as snlphate and nitrate, are more ettii'ient in overcoming the noxious effects 

 of magnesia than less soluble forms, as carlxmate. 



"In applying fertihzers containing magnesia, as in the crude potash salts, liming 

 should be carried on in conjunction unless the soil is known to contain an excess of 

 lime. Where the lime content of the soil is about equal to or less than the magnesia 

 content, lime in a finely divided form, as sulphate, should be supplied with the fer- 

 tilizer in an amount in excess of the magnesia present in the latter. 



"In liming soils the amount of lime and magnesia should be first determine<l in 

 both the soil and the material api)lied. In this way. only can the process be intelli- 

 gently carried out and the best ratio between the two bases for the i)romotion of the 

 growth of crops ])e maintained." 



The influence of the moisture of the soil on the growth of plants, D. 

 Pki.vnishnikov [Zhur. Opnitn. Agron., 1 {1900), No. 1, pp. 3-20). — In this article 

 the author gives the results of his experiments with regard to correlation in the 

 development of plant organs. It is usually accepted that with an increase of moist- 

 ure in the soil the yield of straw increases while the yield of grain diminishes. 

 This is contradicted by the author's experiments with wheat during 2 years, in 

 which there was a steady rise in percentage of grain with an increase in the amount 

 of water in the soil. It has also been claimed that the absolute weight of the grain 

 decreases with an increase of moisture (E. S. R., 7, p. 366), but the experiments of 

 . the author show a different result, there being an increase in absolute weight of the 

 grain with the increase of moisture in the soil during 2 years. Similar results were 

 obtained with flax. The absolute yield of straw increased with the moisture of the 

 soil, owing to the increase in both number and size of stems. The author's experi- 

 ments seem also to corroborate the view of A. Mayer — that the length of the stem 

 has a tendency to reach a maximum sooner than the yield. The length of stem 

 reached its maximum in these experiments with 50 per cent of moisture. Both the 

 length and width of the leaf of beets was found to increase with an increase in the 

 moisture of the soil. It was also observed in the case of beets that there was a 

 decrease of the weight of the dry matter per unit of leaf area and a change of the 

 correlation l)etween the length of the petiole and of the blade, the weight per unit 

 area and the relative length of the petiole decreasing with an increase in moisture. 

 Thus the plant utilizes the same quantity of dry matter in the larger leaf as in the 

 smaller, according as it is obliged to save moisture and lower evaporation, or, on the 

 contrary, bas at its disposal an excess of water. The root system in experiments 

 with beets and flax was found not to increase with the increase of humidity in the 

 same proportion as the total yield. Analyses were made of grains of wheat raised 

 witli different degrees of moisture, but on the same soil under the !-ame conditions 

 of light and temperature. It was found that with higher degrees of moisture there 

 was a lowering of the nitrogen content in the seed. Analogous results have been 

 obtained by A. Mayer, von Seelhorst, and others. It was found also that the dura- 

 tion of the period of vegetation is somewhat shorter when the moisture is greater. — 



p. FIREMAN. 



Investigations on the temperature and moisture relations of loam soils of 

 various kinds and under diflFerent systems of fertilizing, vox Seelhorst 

 {JouT. L<indii\, 4!> {1901), No. 3, pp. '231--2r>0, dgm. 1) . — Observing that plats of soil 

 which had l)een fertilized with i:)otash appeared to dry out quickest after a rain, 

 while those receiving nitrogen and i)hosi)haric acid dried out more slowly and 

 those receiving no fertililer or only phosi)horic acid remained in a moist condition 

 longest, the author undertook to study the relations of these and other fertilizing 

 materials to the moisture of the soil in pot and field experiments. The results 

 of the pot experiments agree with those obtained by Hollrung (E. S. R., 6, p. 00) 



