As crops grow on the farm, they absorb plant nutrients from the soil. Among these, the most important are nitrogen, phosphorus, potassium, calcium and iron. Plants use these nutrients for establishing themselves, growing and becoming fruitful, thus giving us higher and better yields. Nearly all parts of the plant, i.e. roots, the stem, leaves, flowers and fruits have nutrients. However, not all of these parts are edible. Normally, man utilizes the flowers, leaves, seeds, fruits and the tubers. However, the usefulness of any part of a plant depends on the type of produce or plant. Still, the parts that are not useful to man or to domestic animals contain nutrients. In the event that these left-overs are casually discarded or burnt off the farms, the nutrients are wasted and are of no benefit either to the farmer or to the nation. The best way to ensure that left-overs are made good use of is by recycling. This entails decomposing and making compost manure out of them. The same applies to the wastes of animals, especially cattle.
Animals feed on plants and part of this food is utilised by the animals to grow, reproduce, work and live. The remaining part is excreted. This excretion or dung contains many essential plant nutrients.
The best way to utilize the dung is to convert it into compost manure which can be applied to the soil for plant growth. Soil productivity and the life of other living things are thus maintained.
It is my hope that readers will use this book to improve their use of compost manure in the country.
P.S. Ngeze
Rulenge, Tanzania
16th February
1992