Jeff Wimer

Oregon State University


Jeff Wimer currently works as a senior instructor at Oregon State University where he manages the Student Logging Program. Prior to OSU he worked for his families logging and trucking company based out of Albany, OR. Wimer Logging Co. ran 4 tower sides and had 48 trucks. Jeff serves as chairman of the Western Regional Council on Forest Engineering, is President of the Oregon Logging Conference and Vice President of the Pacific Logging Congress.

Jeff has been active in logging safety since the beginning of his career and since 1997 he has been involved with rewriting the OR OSHA Forest Activities logging code. Since 2003 he has been performed just over 24 logging fatality investigations. Jeff has written three books on logging safety. Recently he has been involved with the WA Logger Safety Initiative performing third party audits.

Presentation Topic

Tethered Assisted Harvesting

Presentation Description

Tethered Assisted harvesting has been utilized in Europe for close to two decades. It offers several key advantages to non-tethered harvesting. These systems are recently being introduced to the PNW. Some key limitations to non-tethered include: slope limitations, soil disturbance and safety.

Currently harvesters can navigate slopes up to 70% untethered, but are limited to a downhill operation in such steep terrain. With the utilization of tethered systems these machines have been able to operate on slopes up to 100%.

With tethered systems wheel slip is greatly reduced to almost zero in almost all applications. Newer harvesters utilize an 8-wheel drive system that greatly reduces soil pressure by distributing the overall load. In most dry applications the drive chains can also be removed from the drive system further reducing soil impacts.

The timber industry continues to have the highest fatality rate of all major industries. Within the logging sector a man operating a machine is 10 times safer than working on the ground. Utilization of tethering systems will allow these machines to cover a much larger operational area and reduce the need for men on the ground.