Alley cropping is a system where arable crops are grown in the interspaces (alleys) between rows of planted trees or woody shrubs which are pruned regularly to prevent shading and to provide manure and mulch to the crop. Alley cropping spacing trials were designed at Mtwapa Agroforestry/Energy Centre to establish trends in crop and tree performance under various planting arrangements and densities. Also giving of information on which tree species, which spacings of the trees, and which management practices to use to give maximum economic benefits. The results show that alley cropping with leucaena leads to reduced nutrient loss and is a soil conservation measure
Tag: alley cropping
Soil moisture changes and maize productivity under alley cropping with leucaena and flemingia hedgerows at Chalimbana, near Lusaka, Zambia.
Soil moisture changes and maize yield were studied in 2-year-old alleys of Leucaena leucocephala and Flemingia macrophylla at Chalimbana, Zambia. Field tensiometers were installed at 15, 30 and 45 cm depth, in fertilizer and unfertilized alleys within the double hedgerows, and the first, second and third rows of maize, and were monitored throughout one maize growing season in 1989/1990. In general, maize growth (indicated by height and dry matter measured at roughly fortnightly interval) was higher (P <0.01) in fertilized alleys than in unfertilized alleys, and there were no differences between Leucaena and Flemingia alleys. In both fertilized and unfertilized alleys, the maize plants were 20% shorter (P <0.01) in the first row (nearer the hedgerows) than in the second and third maize rows. Maize dry matter yield was 30% more (P<0.01) in unfertilized Flemingia alleys than in corresponding Leucaena alleys. The grain yield was similar in the fertilized alleys of Leucaena and Flemingia. However, in unfertilized alleys, the grain yield in Flemingia alloys was 50% more than that of the corresponding Leucaena alleys. The fertilized alleys produced twice as much grain as unfertilized alleys when hedgerow prunings were added to the plots. The prunings as a source of nutrient did not appear to have any noticeable effect on crop productivity. The soil moisture content under both Leucaena and Flemingia hedgerow was higher than under the maize rows in the alleys throughout the growing season. The study shows that, under conditions of low fertility and no addition of fertilizers, Leucaena is twice as competitive, as Flemingia for soil resources, and reduces yield of alley-cropped maize from 2.2 t ha1 to 0.7 t ha1. If, however, fertilizer is added, there are no short-term differences between the two hedgerow species.
Surveying farmers’ agroforestry plots: experiences in evaluating alley-cropping and tree border technologies in western Kenya
Evaluation of existing on-farm agroforestry plots should provide useful supplementary information for the design of improved agroforestry systems, in both research and development projects. Such evaluation has been little used, however, largely due to the methodological difficulties of surveying highly variable on-farm plots, and difficulties in identifying key variables for measurement. This paper describes a set of methods and tools used in evaluating plots of alley-cropping and tree borders around crop fields established by farmers working with the CARE Agroforestry Extension Project in western Kenya. Details of survey design, sampling, and implementation are discussed, and suggestions made for carrying out agroforestry surveys in other projects. A condensed version of the questionnaire is appended.
Results of alley cropping experiments with Leucaena leucocephala and Zea mays at the Kenya Coast
This paper covers the 1982 research on hedgerow intercropping which was initiated with 8 different tree species at the Mtwapa agricultural research station to identify ways to improve these yields. The major objectives of the trials were to get information on best tree species, planting spacing, and management practices to give maximum economic benefits to local small-scale farmers
Rooting depth in cropping systems in the humid tropics in relation to nutrient use efficiency
A simple model is presented for calculating the rooting depth of a crop or crop combination required to intercept leaching nutrients for different climatic and soil conditions. Important parameters in this model are the amount of water moving through the soil, which depends on excess of rainfall over evapotranspiration, and the apparent adsorption constant, which depends on the nutrient and soil type involved. Calculations for three time patterns of nutrient supply in relation to nutrient demand show moderate effects of the degree of synchronization on rooting depth required if a high interception fraction is desired. In shifting cultivation systems a deep-rooted fallow vegetation can recover nutrients leached to the subsoil during the cropping phase. The simple leaching model can indicate the combinations of climate zone and apparent adsorption constant for which such interception is possible. It appears that recovery of leached nitrate is only possible in the subhumid zone. In the humid tropics the continuous presence of a deep root system as part of the crop combination on the field is necessary to use nitrogen efficiently, except when acid soil conditions keep all nitrogen in the ammonium form or when an almost ideal synchronization exists of nitrogen supply and demand during the growing season. Some data are discussed on the root distribution of food crops and on the possibilities to establish a “safety-net” under the crops grown in alleys between deep-rooted hedgerow trees.
Trees for Food Security- 2 Project Overview in Uganda
Soil Organic Carbon and Nitrogen in Agroforestry Systems in Sub-Saharan Africa: A Review
Assessment of natural vegetative contour strips for soil conservation on shallow calcareous soils in the central Philippines: accomplishment report for the period Nov. 2000 – July 2003
While a good understanding exists of the effects of low-cost natural vegetative contour strips (NVS) in deep acidic soil environments, little is known about the benefits and constraints of using NVS under severely degraded calcerous soil condition. Calcerous soils cover about 20% of the total land area of the philippines, and are also wide-spread in other parts of Southeast asia. They therefore, characterize an important environment that millions of upland farmers depend upon for a living in the region. Shallow calcareous soils are particularly common in the Central Phillipines covering more than half of the total land area of the Visayan islands. Under shallow soil conditions, the effects of soil scouring can be severe because the entire soil may be removed down to the parent rock material.
Contour grass strips and tillage affect corn production on Philippine steepland oxisols
Cultivated steeplands in the humid tropics require better soil management systems to meet increasing food demands. The objective of this 4-yr study was to evaluate the following four contour soil management systems for corn (Zea mays L.) production: (i) contour moldboard plowing (CP); (ii) ridge tillage (RT); (iii) natural grass barrier strips plus moldboard plowing (GCP); and (iv) grass strips plus ridge tillage (GRT). Eight successive corn crops were grown in limed and fertilized soil from 1992 through 1995. On a total land area basis (cropped area plus the area occupied by the grass strips), the 1995 mean grain yields for RT (10.8 Mg ha1) and GRT (10.3 Mg ha1) were significantly greater than yields for CP (10.0 Mg ha1) and GCP (9.6 Mg ha1). The corn grain yields for the CP and RT systems before 1995 ranged from 1.3 Mg ha1 in 1992 to 8.4 Mg ha1 in 1993, while comparable GCP and GRT yields ranged from 1.4 to 7.6 Mg ha1 Excluding the area occupied by the grass strips, the GRT system had the highest 4-yr average corn yield (7.3 Mg ha1) followed by the GCP (7.2 Mg ha1), RT (6.9 Mg ha1) and CP (6.7 Mg ha1) systems. Yields improved during the 1994 and 1995 growing seasons when the grass was not permitted to grow as tall. The combination of contour ridge tillage and contour grass strips has potential for sustaining crop productivity on highly erodible steepland soils in the humid tropics.
Agronomic and economic appraisal of alley cropping with Leucaena diversifolia on an acid soil in the highlands of Burundi
Although alley cropping has been shown elsewhere to permit continuous cropping, it has not been widely tested in the highlands of east and central Africa where it has the additional potential of controlling soil erosion. The effect of four rates (0, 30, 60 and 90 kg N ha1) of inorganic N on the performance of alley cropping using Leucaena diversifolia as the hedgerow species was studied in the central highlands of Burundi. Significant increase in maize yield (average of 26%) due to alley cropping was only first realised in 1992, three years after the commencement of the trial. In 1993, the average yield advantage of the alley cropping plots was 21%. The prunings augmented the response of maize yield to inorganic N in 1992 and 1993. Compared with the control, economic benefits over the five-year period for all the treatments were negative.