ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 86 Number 4
Bush clearing, tillage methods and the performance of a maize/cassava intercrop on an ultisol in Southwestern Nigeria. (117)
A three season (1995/96 – 1997/98) study was conducted on an Ultisol at Epemakinde, a primary forest area of southwestern Nigeria to assess the effects of bush clearing and tillage methods on the growth and yield of a maize/cassava intercrop. A randomized complete block design with plot arrangement and three replicates was used with the bush clearing (bulldozed and windrowed (BW), bulldozed not windrowed (BNW) and Clear-fell, slashed and burnt (CSB)] and tillage methods (conventional (CT), minimum (MT), traditional (TT) and zero (ZT) as the main and sub-treatments, respectively. Results indicated that maize and cassava heights and number of leaves were generally better in CSB than in BW and BNW plots. Cassava storage root yield was better in the BNW plots whereas maize grain yield in the CSB plots was 5-6%, 8-11% and 15-20% better than in BW and BNW plots after the first, second and third cropping cycles, respectively. Among the tillage methods, no definite pattern was shown for crop heights and number of leaves but TT and MT treatments were significantly (P<0.05) better than CT and ZT, except for number of maize leaves. The best crop yields were obtained in MT plots for maize and in TT plots for cassava. The interaction effects of bush clearing and tillage methods were significant for the crop yield with the CSB + ZT or TT combination supporting better crop yields. However since the CSB is slow, inefficient and laborious, it would hardly meet the food demands of the ever-increasing population. Therefore, the adoption of BNW + MT combination would be more appropriate in primary forests of the humid tropics.
Keywords: Bush clearing, tillage methods, crop yields, Nigeria.