Reduced Impact Logging

Conventional logging systems could be described as "unplanned, haphazard timber harvesting". Reduced Impact Logging (RIL), or Low Impact Logging refers to a timber harvesting technique where there are well-planned stages for the operation. These aim to reduce the negative impacts of the harvest on the forest.

RIL techniques include the following key elements:

• Pre-harvest inventory and mapping
• Tree selection
• Pre-harvest planning of roads and skid trails
• Pre-harvest climber cutting
• Directional felling
• Optimum recovery of usable timber
• Winching of logs to planned skid trails

Tree Selection

There must be a strict diameter limit and selection should discourage the formation of larger gaps in RIL. In the conventional system all viable stems above the minimum size limit are usually taken.

Pre-harvest Climber Cutting

Lianas or ropes cause much damage during harvesting operations as they often connect tree crowns. In the RIL system, the cutting of lianas prior (a few months) to felling therefore reduce the chances of them pulling down surrounding trees along with the logged one.

Directional Felling

This felling technique ensures that the tree is felled in a specific direction. This technique ensures the safety of the felling crew; minimises damage to seedlings or saplings; places logs in the appropriate position to facilitate extraction and when possible, places trees in existing gaps which reduces potential damage to neighbouring trees. If conditions are ideal, trees are felled in a "herring-bone system" ( van der Hout pp. 48), that is, trees are felled at obtuse angles to the skid trail to make skidding easier.

Planned Skidding

Prior to felling the main trail path is flagged while the branch trails are flagged post-felling.

(Information extracted from 'Reduced Impact Logging in the Tropical Rainforest of Guyana' by Peter van der Hout, 1999, Tropenbos-Guyana Series 6)