vii.] GREEN MANURING 185 



grown for the first time on heavy land in a new district 

 has been observed to fail completely, the failure being 

 attended by a complete absence of nodules from the roots. 

 Inoculation with soil from a field which has pre- 

 viously grown the crop about to be sown has often 

 proved a signal success in reclaiming the poor heath 

 lands of East Prussia, by the system of green manuring 

 worked out by Dr Schultz at Lupitz. Very large 

 areas of barren sandy heath land have been re- 

 claimed and rendered fit for the cultivation of the 

 ordinary crop by a system of growing lupins and 

 ploughing in the green crop. Mineral manures alone 

 are employed, latterly basic slag and the Stassfurt 

 potash salts; the lupins accumulate nitrogen from 

 the atmosphere, thus gradually there is built up both 

 humus to bind together the loose sand and make it 

 retentive of moisture, and also a store of nitrogen for 

 the nutrition of succeeding crops. The soil of a field 

 growing lupins every year from 1865 was found in 

 1880 to contain 0-087 per cent, of nitrogen in the 

 surface 8 inches, as compared with 0-027 per cent. 

 in an adjoining pasture. By 1891 the proportion of 

 nitrogen had increased to 0-177 per cent, despite the 

 annual removal of the lupin crop and the fact that 

 the manuring had been with phosphates and potash 

 only. It is in reclaiming these heath lands which 

 have not previously been under cultivation, nor, in 

 many cases, carried any leguminous vegetation what- 

 ever, that soil inoculation from land previously cultivated 

 has given successful results. Dr Salfeld of Hanover has 

 recorded several cases of the successful cultivation on a 

 large scale of various leguminous plants, beans, clover, 

 serradella, lupins, only after previous inoculation with 

 soil. The experiments were made on both peaty (moor) 

 and sandy soils, on which, without inoculation, legumin- 



