Cow Dung: A Composted fertilizer

Published on 01/11/2011

India is primarily an agricultural country. Agriculture contributes the major part to the GDP of India. Apart from the grains, agriculture also produces large quantity of waste that is being utilized in many useful products. Some of the efficient products derived from agricultural wastes are bioethanol, biocoal briquettes, biodiesel and organic manure. Manure is a derived product from waste produced from cattles like cow, buffalo, goat, and sheep. The use of cattle manure, or cow dung, at small scale agriculture and garden is a popular & advantageous practice which the farmers use in many rural areas to make their soil fertile enough.

Generally, this type of manure is not as rich in nitrogen as compared to chemical fertilizers; however, the plants may get damaged due to the high ammonia levels when the fresh manure is directly applied. If this raw cow dung is once composted, it can provide numerous benefits to the garden.

Cow dung can be described as the waste product of bovine animal species. These species also include domestic cattle (“cows”), bison (“buffalo”), yak and water buffalo. Cow dung is the undigested residue of plant matter which has passed through the animal’s gut and the elementary canal. The resultant faecal matter produced after digestion is rich in minerals. The color of cow dung ranges from greenish to blackish, often darkening soon after exposure to air.

Composition of Cow Dung

The composition of cow dung manure is basically digested grass and grain. The grass and grain which they eat is not easily digested and remain up to some extent in their residue. The grass has the high cellulose content, although there are some species of microorganisms found in the guts of these animals. They actively work upon the grass and other substrate material to break it into their simpler compounds. The part which is not digested here is forwarded to stomach where in presence digestive juice its gets digested. It has the high roughage content. Cow dung provides high levels of organic materials and rich in nutrients. It contains about 3 percent nitrogen, 2 percent phosphorous, and 1 percent potassium (3-2-1 npk). In addition, one of the other advantages it is very useful for the farmers to use cow dung manure because it contains high levels of ammonia which is potentially dangerous for pathogens. The growth of the pathogens is almost ceased due to its use. For this reason, it’s usually recommended that it be aged or composted prior to its use as cow manure fertilizer.

Composting Cow Manure

Composted cow manure fertilizer provides an excellent growing medium for agriculture as well as for garden plants. When the cow dung is put for the composting for several days say 3-4 weeks and when turned into compost, it is fed to plants and vegetables. Cow dung manure becomes a nutrient-rich fertilizer because of its satisfactory level of nutrients and fertile efficiency. It can be mixed into the soil or used as top dressing. Most composting bins or piles are located within easy reach of the garden to access them easily.

The processing methodology of cow dung manure is first to collect the animal residue. Heavy manures like that of cows, is mixed with organic substances like vegetable waste, garden debris, hay and straw etc. in addition to the usual organic substances. Small amounts of lime or ash may also be added to promote the carbon content of the manure. The mixed cow dung is then subjected to a pit of predefined dimensions and left for weeks aerobically. Microorganisms or earthworms present in the manure start eating it and converting it into the manure. The process is totally aerobic at the surface but in some cases it is seen that there is there is occurrence of anaerobic environment in the lower levels of the pit and it generates foul smell. To avoid this problem during composting of the manure it should be tossed properly at regular intervals to neglect any possibility of anaerobicity.

There is an important consideration when composting cow manure is the size of bin or pile which has to be used for composting. If the size of the pit would be too small, it would not be able to provide enough heat, which is essential for the composting process. On the contrary if it is too big, the pile may not get enough air. Therefore, frequently tossing the pile is necessary.

Benefits Cow Manure Compost

There are numerous benefits of composting of cow dung. The manure thus produced from composting has satisfactory NPK content. Moreover it also eliminates harmful ammonia gas and pathogens (like E. coli), as well as weed seeds. The composted cow dung manure adds generous amounts of organic matter to the soil. The moisture-holding capacity of the soil can also be promoted by mixing this compost into soil. This allows sprinkling of water less frequently, because the roots of plants can use the additional water and nutrients from the manure whenever needed. There is one more advantage of using this manure is that it increases the breakup of compacted soils through aeration in the soil.

There are also some beneficial bacteria which are found in the compost which have tendency to convert nutrients into easily accessible forms so they can be slowly released without burning tender plant roots thus it is like protective shell to the delicate roots of the crop. Through composting of cow dung manure is produced and if we see it with environmental health perspective, it also produces about a third less greenhouse gases, making it environmentally friendly.

The Way Ahead

Cattle manure which is derived through composting, adds significant amounts of organic material to the soil. With the addition of cow manure fertilizer, we can improve the overall health of soil and produce a healthy, vigorous plant which is a need of a developing nation, India. In India 65% of the total population still lives in the rural areas. If we plan to do this composting at a large or commercial scale it can have future job openings also for people living in rural areas.