Applying indigenous knowledge to restoration of the Lacandón forest in Southern Mexico

People practicing shifting cultivation have accumulated a considerable pool of traditional ecological knowledge. This knowledge can provide practical guidance for tropical forest restoration. The indigenous people of the Lacandón forest of Southern Mexico have a deep understanding of the patterns and processes of succession. For example, they are aware that the invasive fern Pteridium aquilinium (bracken) blocks succession on land following slash and burn clearance and prevents nutrient accumulation. They also believe that the fast growing tree Ochroma pyramidale (balsa) accelerates succession towards mature forest thus increasing the rate at which organic matter and nutrients accumulate in the soil. Here we provide experimental evidence that supports the Lacandón knowledge of the properties of these species. We found that sowing balsa by simple broadcasting in plots previously dominated by bracken resulted in effective establishment when combined with traditional weeding techniques. Balsa established in this way initially increased in height at a more or less constant rate of 63 cm (+- 7 cm) per month. After twelve months growth experimental plots had top heights of over 6m and basal areas of 4.1 (+-0.3) m2 ha-1. We experimentally contrasted this low cost traditional fallow management technique with direct sowing and transplanting of balsa. Our results validate the Lacandón method of directing succession. We conclude that traditional techniques for encouraging establishment of desirable species in degraded tropical fallow can be converted into effective mechanisms for restoring ecosystem function.