1919] AGRICULTURAL, BOTANY. 521 



experiments on different moor soils witli various field and truck crops are 

 reported. 



In most cases liming of moor soils resulted in a decrease in crop yields, 

 or at least no increase. Where upland moor soils were mixed with normal 

 loam soils, the benelicial effect of liming was very small and variable. How- 

 ever, when the loam soil contained injurious iron sulphur compounds liming 

 gave very beneficial results. It was found that the injurious acidity of up- 

 land moor soils could be neutralized to better advantage by adding normal 

 loam soils than by liming. 



The ammonia-fixing' capacity of calcium sulphate, F. E. Bear and A. C. 

 Workman (Soil ScL, 7 {1919), No. 4, pp. 283-291, fig. i ) .—Experiments con- 

 ducted at the Ohio State University are reported on the power of calcium sul- 

 phate to fix ammonia from pure ammonium carbonate. 



It was found that calcium sulphate will prevent to a certain degree the 

 loss of ammonia from a mixture containing volatile ammonium carbonate, and 

 it is considered quite probable that the loss prevention is due to the formation 

 of nonvolatile ammonium sulphate by the double decomposition of ammonium 

 carbonate and calcium sulphate. The ammonia-fixing capacity of calcium sul- 

 phate was found to be apparently dependent on the temperature. The quan- 

 tity of ammonia given off by the ammonium carbonate increased as the tem- 

 perature rose and the percentage of it held by the calcium sulphate decreased. 



The effect of manganese on the grovrth of wheat: A source of manganese 

 for agricultural purposes, J. S. McHakgue (Jour. Indus, and Engin. Ckeni., 11 

 {1919), No. If, pp. 332-335, figs. 4). — Pot and water culture experiments with 

 wheat conducted at the Kentucky Experiment Station to demonstrate the 

 effect of manganese on the growth of wheat and studies to determine a source 

 of this element are reported. 



It was found that manganese in suitable dilution stimulated the growth 

 of wheat, increased the size and nitrogen content of the grain, and apparently 

 performed an important function in the normal growth and development of the 

 plant. 



Chemical examinations of a number of different agricultural limestones, raw 

 rock phosphate, and basic slag showed that the first two materials contained 

 very little manganese, but that basic slag contains about 100 lbs. of manga- 

 nese to the ton. " It is possible that some of the benefit to crops resulting 

 from the use of this fertilizer, on certain soils, may be due to this element." 



AGSICTJLTUEAL SOTAITY. 



Plant succession in relation to range management, A. W. Sampson {U. S. 

 Dept. Agr. Bui. 791 {1919), pp. 76, pis. 6, figs. 22).— A study has been made in 

 the IManti National Forest in central Utah of means for detecting possible over- 

 grazing of ranges, and the author points out what plants may be considered 

 reliable indicators of overgrazing in the various types and how they may be 

 used as guides in revegetation and the maintenance of the forage crop. A 

 list of the most typical primary and secondary species of the respective covers 

 in this region is appended. 



He believes that the character of the native vegetation can be used as a 

 reliable indicator of the condition of the range and of the effect on the plant 

 cover of a given method of grazing. It is claimed that if the invading plants 

 are lower in the succession than the predominating vegetation, the range is being 

 utilized unwisely in one or more respects. If the incoming vegetation is some- 

 what higher successionally than the type as a whole, improvement under the 

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