Restoration of former grazing lands in the highlands of Laos using direct seeding of four native tree species: Seedling establishment and growth performance
Background
Direct seeding has recently regained favor as a lower-cost alternative to planting seedlings for restoration of degraded or abandoned sites. This study reports the establishment and growth performance of 2 pioneer (Pinus kesiya and Schima wallichii) and 2 later-successional (Keteleeria everlyniana and Quercus serrata) native trees broadcasted or buried on former grazing lands in Laos.
Research goals & methods
14 plots were established on former pasture sites in Laos. Seedling establishment was assessed 9 months after sowing and again after 1, 3, and 5 years. significant interspecies and intersite variations were detected for height, diameter growth, and survival. Establishment success was better for buried seeds of Q serrata (49-65%) and K evelyniana (20-59%) than for broadcasted seeds of P kesiya (13-50%), S wallichii (3-34%) and K evelyniana (6-22%). Intersite variation may be related to topographical microhabitat conditions. The two pioneer species achieved better diameter and height growth than the later-successional species.
Conclusions & takeaways
The authors suggest that direct seeding with buried seeds may be a viable option for rehabilitation of abandoned sites, provided that species are chosen based on topographical and other site variations. The authors recommend a reduced seeding rate of pioneer species compared to average planting stockings.
Reference:
Restoration of Former Grazing Lands in the Highlands of Laos Using Direct Seeding of Four Native Tree Species. Mountain Research and Development. 2010;30:232–243. doi:10.1659/mrd-journal-d-10-00031.1.
.Affiliation:
- Southern Swedish Forest Research Centre, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Alnarp, Sweden
- Faculty of Forestry, National University of Laos, Lao PDR
- Département Productions Forestières, Institut de l'Environnement et de Recherches Agricoles, Ouagadougou, Burkina Faso