Farmyard manures

With sodium nitrate, calcium superphosphate, and farmyard manure. 

The organic farmer needs all the farmyard manure that his animals produce it is a valuable commodity for maintaining the fertility of his land, it is free and he cannot use most of the faster acting artificial fertilisers. 

Most farmyard manure is produced by overwintering beef animals indoors, and as most beef and sheep farms are situated on permanent pasture in steep or rocky areas, it is the application of farmyard manure to grassland that is most usual, particularly to fields that are cut for silage or hay. 

The three most important constituents of FYM are nitrogen, phosphate and potash. Additionally, there are the bulky organic parts derived mainly from the straw and the part of the food that has resisted digestion. Granstedt (2002) showed that the majority of the N (about 90%) in farmyard manure served to maintain the soil humus store and the long term capacity to supply nutrients. 

Some assets are difficult to cost accurately for example, the notional financial value of providing a haven for wildlife, or of keeping your part of the river free from excess nitrates. Another example would be the value of keeping beef cattle indoors and then using the farmyard manure to improve soil structure and maintain wheat yield. 

By housing cattle overwinter and composting the farmyard manure, the organic farmer has ready access to a balanced fertiliser that can be spread where most required. The grazing animal does not actually import fertility onto the farm but it does recycle nutrients where it grazes and provides a source of manure when housed. This is as true of sheep, pigs and poultry as of cattle. The only problem with outdoor pigs is that they tend to rip up pastures. 

The answer to the absence of fast-acting nitrogen fertilisers, with arable crops and grassland, has been threefold first, to make much greater use of farmyard manure, and to make sure that it is properly stored and not allowed either to be washed down the drains or to volatilise into the air second, to make much greater use of the legume for its power of nitrogen fixation, particularly white and red clover... 

Whether this enterprise contributes to other enterprises for instance, farmyard manure from the housed beef animals in winter may be essential for the continuing fertility of the silage fields, and straw from the wheat may make a useful contribution to the cost of bedding for the cattle alternating beef and sheep grazing will help to reduce parasite infection for both species (Newton, 1993). 

Further results of introducing cattle are, first, to increase the clover content of the sward, because cattle prefer grass and, second, to increase the proportion of land required for hay or silage for the winter. Cattle often have to be fed hay/silage for six months of the year, whereas sheep require winter feeding for only two months. However, the cattle will produce much more farmyard manure, which can be put back on the pastures that were cut for hay or silage. 

Whereas any N and K that is applied to fields is immediately available to the growing plant and then tends to be washed down out of reach of the plant roots, a large proportion of the P that is applied is rendered unavailable to the plant by being bound into aluminium or iron compounds if the pH of the soil is low, and by calcium compounds if the pH of the soil is high. Although it may seem rather an expensive waste of money, at the time, that as much as 40% of the P applied in farmyard manure should be unavailable to the crop, it does stay in the soil and will become available to the crop in time. 

Yamulki S. Effect of straw addition on nitrous oxide and methane emissions from stored farmyard manures. Agriculture Ecosystems and Environment. 2006 112 140-145. 

FYM Farmyard manure, (2) Extract of Urtica dioica shoots, (3) Calcium-ammonium-nitrate. 

Hansen B, Alroe HF, Kristensen ES (2001) Approaches to assess the environmental impact of organic farming with particular regard to Denmark. Agric Ecosyst Environ 83 11-26 Harinikumar KM, Bagyaraj DJ (1989) Effect of cropping sequence, fertilizers and farmyard manure on vesicular-arbuscular mycorrhizal fungi in different crops over three consecutive seasons. Biol Fertil Soils 7 173-175... 

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