This small tree species is one of the aggressive invasive species in the Mariana Islands, where it can rapidly occupy any cleared areas on limestone soils. The local name for this problematic weedy tree is tangantangan.
When Leucaena trees invade a site and out-compete the other plant species, a homogeneous canopy of the species develops.
Leucaena is a member of the bean family of plants, and it is able to associate with microorganisms in its roots that deliver nitrogen for the plant’s use. This adds to the concerns about how the nitrogen cycling in the invaded sites is being altered and affecting ecosystem services.
Elemental composition of Leucaena leaf litter from five locations throughout the Mariana Islands.
| Nitrogen | 2.56% |
| Sulfur | 0.20% |
| Phosphorus | 0.08% |
| Potassium | 0.53% |
| Magnesium | 0.60% |
| Calcium | 2.96% |
| Iron | 748.00 ppm |
| Aluminum | 19.40 ppm |
| Managese | 72.87 ppm |
| Boron | 65.07 ppm |
| Copper | 8.53 ppm |
| Zinc | 20.53 ppm |
Chemical and physical traits of Leucaena leaf litter that may influence speed of litter decomposition.
| Carbon/Nitrogen | 20.5 |
| Carbon/Phosphorus | 689 |
| Carbon/Potassium | 135 |
| Lignin | 12.4% |
| Cellulose | 15.0% |
| Specific leaf area | 27.6 mm2 / mg |
| Total phenolics | 7,349 Gallic acid equivalents |
Leucaena leaf litter decomposed at a rapid rate compared to the other tree species in this study. About85% of the litter had decomposed by 4 months. One of the concerns with invasive alien species that can so aggressively displace native tree species is what the changes in species composition do to nutrient and carbon cycling in the habitats.
