Fio. 2. Effects of tiirning under a crop of mustard (non-leguminous) upon tlie 

 growth of oats. Both pots were supplied with potash and phosphoric acid 

 equally, hut not with nitrogen. The pot marked "Senf" had mustard turned 

 under ; the other one had none. No immediate effect is shown on the growth 

 of the oats by the previous cro]> of mustard. 



