163 



Peas and vetch are especially adapted for fallow crops, and can be 

 Teconrn Gilded for green manuring. But as they are also goal fodler 

 plants, all that has been said above regarding this subject applies to 

 them with equal force. 



An experimant of interest in this connection was made at the Agri- 

 cultural Institute at Halle, Germ my, in 189 L. About 3 acres of laud 

 was used which had been in winter wheat in 1890 and ia winter rye in 

 1891. A mixture of 191 pounds of white field peas, 44 pounds of com- 

 mon sand vetch, and 35 pounds of yellow lupine seed par acre was sown 

 August 11. The crop was ploughed under October 28. A good growth 

 had been made and the crop was fitted either for green manuring or 

 for feeding. The yield was at tli9 rate of 8,650 pounds of green mite- 

 rial per acre. This contained by analysis 0.5 To percent, of nitrogen, or 

 49.74 pounds of nitrogen per acre, which at 15 ceuts per pound gave a 

 value for the crop for green m inuring of $7.46 an acre. 



In the spring of 1892 white pearl barley was sown on the whole area 

 and also on an adjoining piece not green manured. The crops were 

 harvested August 18, with the following results per acre : 



Yield o'hirley pzr acre with ani without green mmiri-ig. 





Grain. 



Chaff. 



Straw. 





BusheLi. 



Pounds. 



Pounds. 



Plat green minured with paa3, vetch, and lupine 



61.38 



366 



3,260 



Plit not green manured 



61.48 



335 



2,908 



An effect of the green manuring is only noticeable in the amount of 

 straw, which is larger by about 350 pounds per acre where the mixture 

 of peas, vetch, aud lupine had been ploughed ia. 



The barley crop from the green manured plat contained 68. 56 pounds 

 of ni rogen per acre, and that from the plat not green manured 56.6 

 pounds of nitrogen. This difference of 1 1 . 96 pounds of nitrogen is nearly 

 all accounted for by the nitrogen contaiaed in the seed sown on the 

 green-manured plat, so that it may be that on this medium rich soil 

 green manuring was without any effect whatever on the crop immediatly 

 following it. The pea and vetch plants produced root tubercles, and it 

 is probable that had the plants been allowed to fully develop and ripen 

 the effect of the tubercles would have been much more apparent in the 

 amount of nitrogen in the crop ploughed under. But the richer the soil 

 is the larger the proportion of nitrogen which will be taken from the 

 soil and tue less from the air. This nitrogen-gathering appears to go 

 on best in a soil deficient in available nitrogen, as already men ionod. 



The author estimates the green forage as worth $3 per ton for feed- 

 ing, which would make the crop worth $ I l per acre, or $5.54 more per 

 acre thau the estimated value for green manuring:. 



GREEN MANURING ON SANDY LOAM SOILS. 



Compared with the above green-manuring trial on medium rich soil, 

 the result was quite different in a similar trial in 1891 on a sandy loam 

 .-soil poor in humus, A piece of land which for many years had received 



