Effects of Above- and Below-Ground Competition of Shrubs and Grass on Calophyllum brasiliense (Camb.) Seedling Growth in Abandoned Tropical Pasture

background

This article evaluates the above and below-ground competition between grasses, shrubs, and woody seedlings in abandoned pastures in montane Costa Rica.

Research Goals & Methods

One-year-old seedlings of Calophyllum brasilense, a native early-successional tree species, were planted in patches of shrub growth and grass coverage. Seedlings were treated in one of four ways: reduction of root competition, reduction of above-ground competition, reduction of both forms of competition, and control (untreated).

Conclusions & Takeaways

Seedling biomass (above and below-ground) was highest in the plots where both above and below-ground competition was reduced. For all treatments, biomass was higher in the grassy areas than in the shrub areas. Above-ground competition appears to have a stronger effect than under-ground competition. The authors assert than weeding treatments around seedlings multiple times a year are very important in reducing above-ground competition and encouraging seedling growth.