s:1198:"TI Impact of rubber tree planting pattern on Imperata cylindrica dynamics - Exploring weed control through shading using SExI-FS, a forest stand simulator AU Harja D AU Vincent G AU Purnomosidhi P AU Rahayu, S. AU Joshi L AB Imperata is shade intolerant, although little is known of the relative roles of competition for light, water and nutrients in suppressing its growth (MacDicken et al., 1997). A recent report from Purnomosidhi and Rahayu (2002) states that Imperata above ground biomass was decreased by more than 50% after eight months under 88% artificial shading. Acacia mangium has been planted in Kalimantan to control Imperata grasslands. Otsamo (1996) reports that Imperata biomass decreased to 12% of its initial value two years after the plantation of Acacia. Acacia has been selected among other fast growing species for its better ability to compete with the Imperata (Otsamo et al., 1996). Recent results from Rubber Agroforestry Systems experiments conducted by ICRAF however, indicate that while Acacia and other fast growing species are able to partially shade Imperata, their effect on rubber tree growth can be considerable (Mulyoutami et al., this workshop). ";