Between 2003 and 2016, there have been modest shifts in the ways Wisconsin logging businesses harvest and process trees. In Wisconsin, we find that logging businesses use one of three harvest systems.
- Chainsaw-based systems rely on hand felling and processing and typically use cable skidders to drag or forwarders to carry processed trees to the landing.
- The feller-buncher system uses a feller-buncher to fell and pile standing trees, which are then dragged to the landing by a grapple skidder. Next, a delimber and a slasher process the whole trees into sawlogs, bolts and pulpwood sticks. Sometimes, a single machine called a processor performs the limbing and bucking functions.
- The cut-to-length (CTL) system uses harvesters for in-woods felling and processing (i.e., limbing and bucking). Processed logs, bolts and pulpwood sticks are then carried to the landing using forwarders.
- Some businesses report using both the feller-buncher and cut-to-length systems and are classified as “multiple system” for our analysis.
- All mechanized harvesting systems occasionally use chainsaws to fell and process large diameter trees that exceed the size capacity of the equipment. Hand-felling is also more likely when higher-value trees are harvested.
As shown in the figure below, the use of the cut-to-length system has increased, while the number of logging businesses that use chainsaws or feller-bunchers have decreased. In 2016, the portion of businesses using cut-to-length was 53%, while chainsaw-based and feller-buncher systems accounted for 31% and 8% respectively.
In terms of production by the harvest system businesses use, median volume was relatively steady, except for those businesses that use multiple systems which increased substantially over time. This likely reflects that the size of these businesses has increased. Note that annual variability is a factor as seasonality constraints and markets can limit how much a logger can harvest in a given year. For 2016, median production by system was as follows multiple: 11,000 cords, cut-to-length: 5,800 cords, feller-buncher: 3,100 cords, and chainsaw-based 1,300 cords.
If we categorize businesses by their annual production instead of harvest system (i.e., bars in figure below), we find that the largest portion of firms produce between 1,001 and 5,000 cords annually. This is true across the three study periods. What has changed though, is the percent of of the harvest volume produced (i.e., lines in figure below). In 2016, the largest businesses (> 15,000 cords) accounted for 50% of total volume harvested by all businesses In 2003, they only contributed 30%. In essence, more of the wood is being harvested by larger businesses. [paragraph and chart below revised 8/1/2018 to reflect corrected data]
Author: Mark Rickenbach
Links to complete series on Week 1 post.