Peranan Chromolaena odorata dalam meningkatkan kesuburan tanah pada lahan alang-alang

Chromolaena odorala is seen as one of the worlds worst weeds, but is also claimed to improve sod fertifity. An experiment was initiated to test the sod changes under Chromolaena odorata, Imperata cylindrica (alang-alang) and two other fallow species. This experiment was conducted at Research Station of Biological Management of Sod Fertility (BMSF) project at Karta village, District of South Sungkai. Regency of Kota Bumi. North Lampung, Sumatra, Indonesia- The experiment was conducted from February 1995 to June 1995. The experiment was arranged in randomised block design with 4 replications. one of which was used for destructive plot. The treatments were four cover crops for fallows species : Chromolaena odorata, Pueraria phaseoloides. Pellophorum dasyrachis and Imperata cylindrica. (alang-alaig) Six months after planting, alang-alang produced the largest biomass (21.94 Mg ha7l), followed by Peltophorum (19.15 Mg lig-1), Chromolaena (11.22 Mg ha-1), and Puera ria (6.33 Mg ha") respectively. The nutrients content of Chromolaena were higher than that in Imperata cylindrica (alang-alang). The contribution of N mid K in Chromolaena were also higher than that in Imperata cylindrica (alang-alang). Until 6 months after planting Chromolaena could not increase the amount of cations in the sod, but this plant could conserved sod organic matter.