Chromolaena odorata in slash-and-burn rice systems of Northern Laos uri icon

abstract

  • Chromolaena odorata, introduced to Laos in the 1930s, has become the most abundant weed and fallow species in slash-and-burn fields over a wide range of land use systems, elevation, and pH ranges. Regeneration from roots, high seed production and easy dispersal allow for the rapid colonization of fields in the initial fallow period. At rice harvest, after a 1-year and a 2-year fallow, the total aboveground biomass in monitoring plots was 1.4, 10, and 15.4 t ha(-1) with 16, 48, and 29% contribution by C. odorata, respectively. With progressing fallow period C. odorata is gradually replaced by tree and bamboo species. Slash-and-burn farmers preferred C. odorata over other fallow species common in their fields. Chromolaena odorata is an excellent fallow species considering its fast expansion after crop harvest, high biomass production, weed suppression, and fast decomposition rate. Some of these properties may, however, become a serious disadvantage when farmers gradually change to land use systems that integrate grazed fallow, crop rotation, and/or fruit and timber plantations.

publication date

  • 1995
  • 1995