Thinning Acacia to Optimize Conditions for Underplanted Native Species

Acacia species are widely naturalized in the Marianas islands and widely planted with the intent to stabilize eroding soil surfaces, provide nitrogen-rich organic material to the soils, and replace flammable grasses. The long-term plan for most Acacia plantations is to under plant them with native woody species. However, there is little information and very limited practice of thinning the Acacia overstory to optimize conditions for under planted native species. Thinning and/or removal of “nurse crop” tree species is a common silvoculture practice worldwide and in traditional Micronesian agroforestry, but actual thinning practices are most effective if calibrated to the local environment, the nurse crop species, and the species under planted.