Control of Pseudotsuga menziesii in Chile
Pseudotsuga menziesii (Pinaceae) is native to North America and considered an invasive alien species in Argentina, New Zealand and Chile. In Chile, the initial introduction of non-native conifers was used to recover degraded land. However, some of these species present a high invasion risk when they are not properly managed. Impacts can include negative impacts on biodiversity and ecosystem services. Pseudotsuga menziesii is listed as invasive in south-central Chile where it can establish beyond the original plantation area. In order to assess the negative impact of P. menziesii, five longitudinal transects (10×100 m) were established in a protected area with an altitude ranging from 900 to 1 060 m a.s.l. The five transects were established with varying distance from a P. menziesii plantation and included two habitat types, (1) within the native forest and (2) open scrub areas. Forest structure, soil nutrients, the floristic composition, and pine regeneration before and after control was measured in each site. Results show that in the native forest, soil nutrient availability and the density of P. menziesii decreased with distance from the plantation. Other studies have shown that the invasion of P. menziesii is influenced by abiotic factors including soil nutrient availability. An increase in native species cover was found after removing pines, but P. menziesii can readily re-invade native forest habitats after its removal. In open scrubland areas, P. menziesii density was lower than in native forest conditions. The results indicate that repeated control measures against P. menziesii are needed at the early stages of invasion and plantation management should include measures to prevent spread into natural areas.
Sources
Fuentes-Ramirez A, Vargas-Gaete R, Toy-Opazo O, Muñoz-Gómez N, Salas-Eljatib C, Pauchard A (2024) Control of invasive conifers in temperate Andean forests promotes native vegetation restoration, but requires continuous management. Trees, Forest and People. https://doi.org/10.1016/j.tfp.2024.100581