Overview

The skidder is a large front line forest machine used in modern forest harvesting operations.

The main job of the skidderis to skid or the term commonly used snig logs or full trees held by a large grapple attached behind the machine in a toeing action.

For some ground conditions or difficulty in getting logs or trees, the skidder may be fitted with a powerful winch and cable.

A Skidder can be fitted with different implements, depending on the harvesting

Implements that can be fitted to a skidder are:

• Grapple - and there are many types;
• Winch and cable - used to pull logs or whole trees;
• Dozer blade - used for levelling, repairing snig tracks, pushing up slash;
• Front end slash grab - used for removing bulk slash;
• Single or Dual arch.

For example the it can be used in thinnings, clear fell,  native forest thinning or salvage work

Operations of the skidder have to be conducted to manufacturer specifications, contractor, forest owners and site coupe plan policies and procedures.

Operating the skidder to forest terrain and changing weather conditions is of the utmost importance when extracting trees.

The picture below shows the main working components of a six wheel drive dual arch skidder.

Fig 1 Six wheel drive 635C Tigercat skidder.

On this operation the blue gum trees will be fed into a heavy production mobile chipper. 

Fig 2 Blue gum trees being felled and bunched.

Fig 3 Four wheel drive skidder snigging whole trees to a landing site.

Below is an example of trees felled, bunched and presented in a neat order for the skidder operator to pick up and transport to a landing site.

While the feller buncher operator is responsible for the felled trees, their role is also vital in presenting the bunched trees neatly for extraction.

Fig 4 Neatly felled blue gum trees ready to be skidded to a landing.	Fig 5 The Tigercat skidder travelling back to the landing site with a large grapple full of blue gum trees working.

During clear felling of plantation trees, the skidder works in conjunction with the feller buncher.

Throughout the day the operators keep in contact to make sure the operation is performed efficiently and without incident.