TO WHAT EXTENT SHOULD A SOIL BE LIMED. 377 



and still greater is the decrease from pot No. III., to No. IV. 

 There can therefore be no doubt that the ratio of 3 parts of CaO 

 to 1 part of MgO in the soil is the most favorable for buckwheat. 

 A further increase of lime, to judge from observations with other 

 crops, would in all probability depress the yield. 



The second series, B, of buckwheat plants, (8 plants in each 

 pot) was cut on June 28th, with the following results : 



Buckwheat. 



No. I. 



CaO : MgO 



3 = 1 



No. II. 



CaO : MgO 

 2 : 1 



No. III. 

 CaO : MgO 

 1 : 1 



No. IV. 

 CaO : MgO 

 1 : 2 



Total weight. 



340 gr. 



275- gr. 



281. gr. 



240. gr. 



Average weight. 



42.5 gr- 



34-4 g<". 



35 1 g'"- 



30.0 gr. 



Average height. 



75. 1 cm. 



67.1 cm. 



67.3 cm. 



56.3 cm. 



Number of leaves. 



267. 



182. 



226. 



173- 



Weight of ( ripened, 

 the seeds. ( unripened. 



64-5 e r - 

 6-5 gr. 



58.0 gr. 

 11.0 gr. 



58.5 g r - 

 8-5 gr- 



56.0 gr. 

 8.0 gr. 



Weight ot ico 

 ripened seeds. 



4 3' B r - 



S-7o gr. 



4->2jgr. 



4.64 gr. 



We observe from this comparison that also here the richest 

 yield as to straw and seeds was obtained with the ratio 3 CaO 

 to 1 MgO while on the other hand the single seeds were best 

 formed with the ratio 2 parts CaO : 1 part MgO, since 100 seeds 

 weighed here considerably more than in the other cases. 



Experiment with Oats. 



On April 10th, four pots were sown with oats, each receiv- 

 ing 15 seeds. The rate of germination was about equal in the 

 four pots. On April 28th, the young plants were thinned out 

 to eleven in each pot. On May 12th, it was noticed that in pot 

 No. IV., some leaves were withering and becoming brown, which 

 phenomenon had made considerable advance on May 30th. 



