THE AGRICULTURAL JOURNAL. 



243 



the contents of the soil by the amount of 

 the nitrogen they have been able to take 

 up from the atmosphere. 



It has been estimated that such crops 

 supply from to If-O lbs. of nitrogen 

 per acre, about equal to the amount of 

 nitrogen contained in from 2^ to 8 cvvt. 

 of nitrate of soda, or 2 to " 6 cwt. of 

 sulphate of ammonia. 



There are so many -varieties of legum- 

 inous plants, both susceptible and hardy, 

 that they can be selected to suit almost 

 any climate, hot, temperate, or cold. For 

 the purposes of manuring they are usully 

 sown in midsummer or autumn, so that 

 they may receive sufficient heat and 

 moisture to enable them to attain sufficient 

 growth to permit of their being turned in 

 at the end of the year, or in the early 

 spring. The exact time of planting is 

 regulated by the system of cultivation, 

 previous crops, and individual circum- 

 stances. When grown late in the year, 

 at a time when the ground would other- 

 wise be bare or the standing crop inactive, 

 they fill the land at a time when the 

 nitrifying bacteria are most active, and 

 when a great part of the nitrates they 

 form are liable to be lost by leaching. In 

 the presence of active root growth the 

 nitrates are taken up by the plant as they 

 are prepared, and the loss in this direction 

 is greatly minimised. 



It may be necessary to manure the green 

 crop, which on the face of it looks like 

 robbing Peter to pay Paul, but it is not 

 so ; the manure so applied not only 

 increases the yield of the soiling crop, but 

 it is still available for the standard crop, 

 both through the medium of the vines 

 ploughed under, and the remainder which 

 has not been utilised. Besides, the im- 

 provement effected on the more insoluble 

 parts by the availability brought about 

 during the process of decay by its 

 chemical action, makes much of the in- 

 soluble matter fit for use by the new crop. 



The most beneficial manures to apply 

 to the ■ leguminous crops are phosphoric 

 acid, potash and lime, and in some cases 

 it will prove of great benefit to assist them 

 to a vigorous growth by the,addition of a 

 little soluble nitrogen. 



Certain precautions have to be observed 

 when green crops are grown simply for 

 manurial purposes. It is always advis- 

 able to see that sufficient dressings of 



lime are given, both for the benefit of the 

 croj) itself and to neutralise the excess of 

 acid which may occur during the decay 

 of so much rank vegetable m itter. The 

 lime will tend, to a large extent, to 

 counteract any evil eEEects arising from 

 this cause, and will promote a healthy 

 condition for the nitrifying organisms. 

 Good and thorough cultivation will also 

 assist by aeration of the soil, and exposure 

 to the influences of the atmosphere, and 

 by the inclusion of oxygen in the inter- 

 stices among the soil particles. In warm, 

 moist climates it is inadvisable to turn in 

 such a large amount of green moist her- 

 bage, decay is too rapid under these con- 

 ditions, and a consequent souring of the 

 soil ensues. Far better, it would be, to 

 let the plant complete its growth, and 

 allow the foliage to lie on the soil as a 

 mulch for some time during the winter, 

 and plough it under when it has become 

 drier and less succulent. A certain 

 amount of loss would necessarily occur in 

 the asrial part of the plants, but probably 

 as much would be lost were the plough- 

 ing in to be done in autumn, and rains 

 were to enter the freshly turned over 

 ground. In colder climates there is less 

 to fear from ploughing in in the autumn, 

 as energetic decomposition is retarded by 

 the cold, and the formation of acid is 

 slow, and more easily dealt with. 



The subject has been here treated in 

 general, and has been confined to the 

 manurial side of green crops only. They 

 have an important value as feeding stuffs 

 as well, but it has been thought better to 

 refer to these when the individual crops, 

 and their methods of cultivation, are dis- 

 cussed. 



Agricultural Showsm 



Lion's River Division, Howick, Thursday, 

 June 27th. Secretary, G. Hutchinson, Balgowan. 



Natal Poultry Club. Annual Show, Market 

 Hall, Maritzburg, Is July. Hon. Secretary 

 J. Anderson, 272, Longmarket Street, Pieter 

 maritzburg. 



Ixopo, Wednesday, July 3rd. Entries close 

 June 22nd. Secretary, A. Keith, Ixopo. 



Richmond, Wednesday, July 10th, Secretary 

 John Marwick, Richmond. 



Alexandra, Umzinto, Thursday, July 11th. 

 Entries close July 2nd. Secretary, R. G. Archi- 

 bald, Umzinto. 



New Hanover, Wednesday, July 24th. Secre- 

 tary, H. A. Light, York. 



