Agroforestation of Grasslands in Southeast Asia: WaNuLCAS Model Scenarios for Shade-Based Imperata Control During Tree Establishment - Smallholder Tree Growing for Rural Development and Environmental Services - page 150

● Weeding in the zone directly surrounding the tree is essential for tree establish-
ment in nearly all tree species tested.
● Crop growth in the zones with increasing distance to the tree (zones 2-4 of
WaNulCAS model; Van Noordwijk et al. 2004a) is less competitive for the tree than
allowing Imperata regrowth, but clean weeding has no advantage on tree growth.
● Adequate Imperata control with the use of medium-to-slow growing tree species
is contingent on landscape level control of the risk of fires spreading.
● Agroforestation with fast growing trees with a 70 percent probability of success
can be achieved as long as the risk for fires entering the plot is kept below
15 percent.
● A landscape mosaic with plots in different phases of agroforestation may
enhance the overall probability of success, and allow for plots of valuable, slow
growing trees to be interspersed with faster growing trees that will reduce fire
risk for the surrounding plots.
Acknowledgements The results presented here were obtained in the Smallholder Agroforestry
on Degraded Soils (SAFODS) project, supported by the EU(ICA4-CT-2001-10092).
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