FIELD CROPS. 627 



The rational use of chemical fertilizers, P. Liechti (Ann. Agr. Suisse, 1 {1900), 

 No. 7, pp. 2.^3-268, fi(js. 4)- — The extent of the use of fertilizers in the Canton of 

 Berne is discussed and an account is given of pot experiments by the Wagner method 

 with oats to test the relative efficiency of different fertilizers on soils of different 

 character. Analyses of the various soils experimente<l with and the details of the 

 experiments are given in full, with a discussion of the practical application of the 

 results. 



The use of lime upon Pennsylvania soils, W. Frear (Pennsylvania Dept. Agr. 

 Bui. 61, pp. 170, figs. 3, map 1). — This is a detailed discussion, based upon investiga- 

 tions at the Pennsylvania Station and elsewhere, of the agricultural uses of lime; the 

 limestones of Pennsylvania; the burning, slaking, and quality of different kinds of 

 lime; the functions of lime in plants and soils; the influence of liming upon soils and 

 the relative value of magnesian limestones; and methods of liming. An appendix 

 gives analyses of Pennsylvania limestones compiled from various sources. 



Field experiments with night soil near Posen {Mitt. Dent. Landw. GeselL, 15 

 {1900), Xo. 37, pp. 223-238). 



FIELD CROPS. 



Subexperiment farms, W. M. Hays et al. {Minnesota Sfa. Bui. 

 68, pp. oo7-7J0, Jigs. 38, dgnis. 24). — Results are here recorded of 

 experiments conducted at the 3 subexperiment farms in the State, pre- 

 ceded in each instance hy general notes on the purpose of the farm 

 and its method of management b}' W. M. Liggett. 



Experiments at Coteau farm (pp. 563-651). — This farm is located in 

 southwest Minnesota, where droughts are frequent and often severe. 

 The work of the farm has therefore been mainly directed toward 

 ameliorating their effects by different systems of tillage, manuring and 

 cropping, the use of shelter belts, etc. 



In a study of the amount of soil moisture best suited to the growth 

 of flax in upland soil containing 13.02 per cent of organic matter and 

 in lowland .soil containing 28.6 per cent, the best result in the case of 

 the upland soil was obtained when 30 per cent of water was used. 

 With lowland soil 100 per cent of water gave the strongest flax. 

 These results are believed to show that the larger the amount of 

 organic matter in the soil the greater the endurance of plants to 

 extremes of drought and rainfall. 



The results obtained in farm tillage experiments are reported in 

 crop yields and soil moisture content and shown by tables and a com- 

 prehensive .S3'stem of charts. The moisture content of the upper 2 ft. 

 of a soil which had been in wheat and yielded about 2 tons of grain 

 and straw per acre averaged about 15 per cent less than a cultivated 

 soil which had borne no crop. Using SO lbs. as the average weight of 

 the soil, it is estimated that for each pound of dry matter produced in 

 this case some 261 lbs. of water was required. 



The losses of moisture in a field of corn occasioned by the growth 

 of 3,540 lbs. of weeds per acre was very marked, especially at depths 

 of from 3 to 6 in., and the corn crop was reduced from 12,762 lbs., 

 15410— No. 7 3 



