Wind dispersal and dormancy are biological agents for dispersal and persistence of Tithonia diversifolia seeds. This study combined field and laboratory experiments to establish the dispersal capability, persistence and weed seedbank of Tithonia diversifolia seeds into new niches. Experiment one was set in a Completely Randomized Design to determine the relationship between Tithonia diversifolia seeds and wind speed. Results indicated that wind provides long-distance dispersal that can disseminate weeds in new areas. As height of the plant increases, dispersal distance increases. Experiment two measured the distance of newly established Tithonia diversifolia weed from pioneer plants. Results indicated that over a period of one year, the weed can disperse 50 m away from the pioneer plant. Experiment three tested seed dormancy of same weed. Results shows that highest germination was found on seeds harvested on 2 m at 6 weeks. There was significant difference (p < 0.05) between week 6 and any other periods on germination. The least germination was found on seeds planted on week 6 at 4 and 5 m. There was no significant difference (p < 0.05) on germination on day one of harvesting at different heights. It is therefore recommended that Tithonia diversifolia be controlled before flowering.

Keywords: Colonizer, dispersal, dormancy, ecosystem.