Water Harvesting Furrows Options for Maize Production in the Southern Rangelands of Semi-Arid Kenya

Abstract

The Southern Rangelands of Kenya's drylands are prone to unreliable and insufficient rainfall making crop production risky and food insecurity and poverty rampant. The drylands are characterized with low and erratic rainfall and high transpiration rates. In order to improve crop and tree production in these areas, sustainable drought mitigation farming methods, through better on-farm rainwater management are required. A study was conducted to determine the effect of using mechanized furrows made using the Vallerani technology, vis-a-vis the traditional furrows made using the oxen plough to harvest rainwater, on the yield of maize in Kibwezi and Kiboko Divisions in the Southern Rangelands of Kenya. Other common water harvesting methods include creation of surface and earth dams, roof catchment, trapping road runoff and directing the water into the farm, and digging of tied trenches. The Vallerani technology involved use of a tractor with a calibrated Delphino plough to make tied ridges and furrows during seedbed preparation before planting. Elev,en farmers were selected from Mtito Andei and Kibwezi Divisions. Maize was planted in 5 m x 3 m plots with a total of 66 plants and a sample of 24 plants harvested. Mechanized furrows gave higher (P<0.05) maize grain yields (2073 kg/ha) than those under oxen furrows (1322 kg/ha). The Pioneer maize variety gave higher (P<0.05) maize grain yields (1961 kg/ha) than the local variety (1506 kg/ha) and as such should b recommended for the area. The 3 m (furrow to furrow) by 0.15 m (plant to plant) gave higher (P<0.05) maize grain yields (2072 kg/ha) than the 1.5 m (furrow to furrow) by 0.30 m (plant to plant) spacing. The use of the calibrated Delphino plough in making tied ridges and furrows during seedbed preparation before planting should be encouraged in the arid and semi-arid areas of Kenya.