Most of us don’t take the time to consider how forestry machines work and work together to efficiently, sustainably, and safely harvest timber off of our properties. Well, that is going to change right now.
Ever since I saw my first timber harvester, I have been fascinated by these machines. The combination of speed, power, efficiency, accuracy, and high tech put them in a class by themselves when it comes to heavy machinery. Most of us don’t take the time to consider how these machines work and work together to efficiently, sustainably, and safely harvest timber off of our properties. Well, that is going to change right now.
Let’s start with the skidder. What seems like a simple machine designed to drag (skid) felled trees and logs to the landing is really much more than that. Some skidders have a grapple on the back for grabbing onto large bunches of trees while others have a cable and winch for reaching out and pulling trees/logs to the vehicle. The former is most commonly used in large clearcutting operations while the latter is often utilized in selection harvests.
Forwarders have the same role as skidders in a harvesting operation, but carry their loads rather than skid them. The forwarder’s articulated boom and grapple allow the operator to sort logs in a bit more efficient manner than a skidder. Also, carrying trees/logs is an advantage when soil disturbance needs to be minimized. However, skidders are the preferred vehicle when soil disturbance is needed to create the best seed bed for certain trees to grow.
Skidders and forwarders do a lot of the grunt work of the operation. Along with hauling logs, they clear trails and roads and do much of the post-harvest clean up.
That takes us to the harvesting machines. Some do nothing more than drive up to the trees, grab them, cut them at the stump, and then drop them. Others will do that and then place them into piles or bunches. Finally, some will do all of that and process the trees into logs of certain dimensions. A logger will choose which of these to operate based on the kinds of conditions they will be working in and what kinds of products they will be producing.
The equipment that gets most of the attention are the cut-to-length harvesters. The cockpit for these machines is something out of NASA and Nintendo with two joystick controls, computer readouts of trees harvested by species, and much more. Operators go through a lengthy training regime to learn how to use these half-million dollar pieces of equipment. In the end, it is worth it for some loggers as they can accomplish the same types and amount of work as a couple of (or sometimes three) machines and operators.
That leaves just the specialized machines including the delimber, slasher, and processer. These usually work in concert with feller-buncher harvesters on large clearcuts. After the delimber does its work, the slasher cuts delimbed trees into the proper length for transport and sale. Sometimes these two tasks are combined into one machine called the processer.
Another specialized but common piece of equipment is the chipper. Rather than process trees into logs, some loggers will chip the trees and transport them using chip vans. Sometimes these operations are referred to as “biomass” harvests, as the logger is utilizing all the tree’s growing parts (excluding roots) rather than just the main stem of the tree. These chips can be utilized for the creation of a number of different products along with being burned for energy production.
Now that you know the players, it is time to fit them all together. The process looks something like this. Trees are felled by the harvester and possibly stacked or processed into logs depending on the machine in use. Then a skidder or forward come along and move the felled trees and logs to the landing where they are stacked and await transport to the mill.
There are a number of different combinations these pieces can be assembled into and it depends on the type of operation and harvests the logger wants to have and conduct. The terrain, the size/value of the trees, the number of trees to be harvested, and the needs of the landowner all play into which equipment is best suited for a harvest.
Horse skidding and hand felling with a chainsaw still have a place in harvesting operations today. However, they are a small percentage of the work taking place in our woods. Horse logging can’t compete with mechanized operations in regards to volume of timber harvested. Instead, it is desired by some landowners for its aesthetic value and a perception of less environmental impact.
Spending time watching the well-choreographed ballet of machines in the woods as they turn standing trees into products ready for shipping is a real treat for me and something I don’t get to do nearly enough.
Learn more about these machines in “Logging Methods for Wisconsin Woodlands“.