Multiple Cropping System Notes (CRP 203 Week 5)

**[MULTIPLE CROPPING SYSTEM]** Multiple cropping systems: are a wide -spread form of traditional Agriculture in the tropics and they are very important among traditional farmers. Most of the food consumed in the past and even now in the tropics was produced in small scale farms where multiple cropp...

**[MULTIPLE CROPPING SYSTEM]** Multiple cropping systems: are a wide -spread form of traditional Agriculture in the tropics and they are very important among traditional farmers. Most of the food consumed in the past and even now in the tropics was produced in small scale farms where multiple cropping system are commonly practiced. Multiple cropping is the growing of two or more crops on the same land during a year. The essence of multiple cropping is the intensification of crop production in time and space dimensions. Multiple cropping system can be seen clearly on the basis of area of production, other resources, yield per unit area, time and space dimensions. **Classification of multiple cropping system:** Multiple cropping system are better classified according to the degree of intensification in time and space dimensions. According to Andrews and Kassam (1976) multiple cropping system are classified and defined into the following: Intercropping and sequential cropping. A major distinction is made retween the two types. Intercropping and sequential cropping differ in relation to the intimacy or contiguity of individual crop stands , relative time of planting , the duration of mixing and the spatial arrangement of component of the mixture. 1\. **Intercropping-** It is the growing of two or more useful crops simultaneously on the same field per year in proximate but alternate rows. Crop intensification is in both time and space dimensions. There is intercropping competition during all or part of crop growth. Farmers manage more than one crop at a time in the same field. Intercropping consist is mixed Intercropping, row Intercropping, strip Intercropping, and rarely Intercropping. i\. **Mixed Intercropping**- growing of two or more crops simultaneously with no distinct row arrangement. This is simply called mixed cropping. ii\. **Row Intercropping-** growing two or more crops simultaneously with one or more crops planted in rows. iii\. **Strip Intercropping-** growing two or more crops simultaneously in different strips wide enough to permit independent cultivation but narrow enough for the crops to interact agronomically. iv\. **Relay Intercropping**- growing two or more crops simultaneously, but with one or more of them planted after the first crop has reached reproductive stage of growth but some time before harvesting. 2\. **Sequential cropping-** Growing of two or more crops in sequence on the same field per year. The succeeding crop is planted after preceding one had been harvested. Crop intensification is only in the time dimensions. There is no intercrop competition and farmers manage only one at a time I\'m the same field. Equential cropping consists of double cropping, triple cropping and ration cropping. i\. **Double cropping-** growing two crops a year in sequence. ii\. **Triple cropping**- growing three crops a year in sequence. iii. **Quadruple cropping-** growing four crops a year in sequence. iv\. **Ration cropping-** cultivating crop regrowth after harvest although not necessarily for grain. Andrews and Kassam(1976) also gave some related terminologies used in multiple cropping system. Some of them are included in the following: mono - cropping, cropping pattern , mixed farming , crop competition, crop rotation, bush fallowing , and shifting cultivation. i\. **Monocropping-** growing only one type of crop in a given area of land. That is the repetitive growing of the same crop on the same land. At times, monoculture, pure stand or sole cropping is used instead of momocropping. ii **. Cropping pattern-** The yearly sequence and spatial arrangement of crops, or of crops and fallow, on a given area. iii. **Mixed farming -** cropping systems that involve the raising of crops and animals. iv**. Crop competition-** The response of an individual plant species to it\'s environment as modified by presence of another individual plant species ( Hall, 1974a). Crop competition occurs when one or more growth factors are limiting. The plant species better equiped to utilize a growth factor increases its yield at the expense of the other plant species which suffer a yield which suffer a yield decrease. **Crop Rotation-** It is the practice of growing different crops in planned sequence or succession on the same piece of land. Yam could be followed by maize, then sweet potato, then cowpea and then tlyam again. Some principles must be followed in order to meet the main objectives of crop rotation. Deep rooted crop must not follow another deep-rooted crop, heavy feeder crop must not follow another heavy feeder or soil depleting crop, shallow feeder crop must not follow another shallow feeder crop, and a pest or disease - host crop must not follow another crop that will be a host to the same pests or diseases. For example, maize must not follow follow cereal crop like rice. They are both susceptible to stem borer. **The following terms are common in crop rotation:** Interplant with (ipw)- two crops planted at different times are grown on the same plot but the one that is planted later remain in the plot after the first one have been harvested e.g. yam ipw cowpea: intercropped with (icw)- two crops planted at the same time on the same plot but the one that is planted later is harvested first e.g. yam ice maize, and followed by (fb)- planting of another crop on a plot from which the first crop has just been harvested e.g. groundnut fb late maize. **Advantage of crop rotation include:** diversification of crop production, more even spread of labour, more efficient utilization of resources, increments in nitrogen levels when leguminous crops are included, conservation of soil moisture in dry areas or season, and efficient control of pests and diseases by breaking the life cycles. A typical example of four-year crop rotation, consisting of yams, maize, cowpeas and sweet potato or cassava is given below. [Season. 1 2 3 4] 1\. Yams Maize Cassava Cowpea 2 Maize Cassava Cowpea Yams 3 Cassava Cowpeas Yams Maize [4 Cowpeas Yams Maize Cassava] vi**. Shifting cultivation and bush fallowing-** shifting cultivation is a system in which a farmer crops a piece of land for one or two years and then moves on to crop another piece of land, leaving the first one to return to bush fallow. This is therefore a bush fallow system. After about 5-10 years of the bush fallow, the farmer again return to the piece of land to crop it. Shifting cultivation and related bush fallow cropping system constitue the predominant practices on large areas of the tropics extending more than 200 million people (Moody, 1975). Under shifting cultivation the land is fallowed than it is cropped. However the length of fallow depends on the amount of land available, pressure of population, level of fertility, rapidity of regeneration of the fallow, and the various other factors like pests, disease and weed encroachment. Therefore shifting is a farming system whereby annual crop production is alternated with period of vegetative fallow. It is a rotation of land instead of crop. The essential features of shifting cultivation and bush fallowing are (1) the rotation of fields rather than crops with short period of cropping alternating with long period of natural fallow, (2) the use of slash and burn methods to clear the land of native vegetation, and (3) the maintenance of fertility by allowing the vegetation to regenerate. Bush fallowing is the only means if replenishing the land under shifting cultivation. However , there are disadvantages consisting of (1) it is wasteful of land , since a large percentage of the land lies fallow at any given time , (2) it discourage the settling up of permanent farm structures such as irrigation facilities, good houses and store houses. Since the site is to be abandoned after one or two years , only temporary structures can be erected , and (3) it requires a great deal of labour especially because the tedious process of land clearing has to be repeated almost each year. The bush fallow period is very important and necessary for the depleted soils to regain their normal structure and fertility.