SAW SHOP: WEDGING AND MECHANICAL ASSISTED FELLING

In past articles, the Five Step Felling Plan has been addressed. Step two of the plan deals with the lean of the tree. Every tree is going to have two types of lean; side lean, left or right, and lean forward or backward.

If the tree is leaning forward toward our intended target, we usually do not worry too much that it will fall. Gravity will help us in that situation. But when the tree is leaning back from our desired target, gravity works against us. So, there are several options when it comes to dealing with back lean. Once we have read our tree and determined it has back lean, we should look to see if we can change our direction of fall or our target.

If there is nothing around to impede the tree from going opposite of our first objective, then the simplest solution could be to change our desired direction of fall. If that is not an option, then we must move the tree in our desired direction of fall by pushing, pulling, or lifting the tree.

Lifting

The most common tool for dealing with back lean is our wedges. "To be effective in directional felling, a timber cutter must have wedges". Proper placement of a wedge can help lift the tree to counter the back lean. During training, I am often asked, "Where do I put the wedge?" Once the bore cut is made and the hinge is established, a wedge can be placed directly behind the hinge. This will cause the tree to lift faster, but it will take more effort to drive the wedge.

Placing the wedge in the back of the tree, pointing toward the hinge, will allow the wedge to drive in easier but will lift slower. Setting two wedges side by side near the hinge can help with lifting. Alternate hitting of the wedges will help lift the tree faster without as much effort.

The back lean may be greater than the amount of lift that one wedge will provide. In this case, wedges may be stacked to provide more lift. When stacking the wedges, be sure to cross the wedges and tap carefully to prevent the wedges from kicking out. A little tip, adding a little dirt between the wedges will also help. Some wedge manufacturers have designed wedges with grooves to help lock the wedges in place when stacking.

When dealing with side lean and back lean, there are times a wedge on the bad side near the hinge will help protect the hinge and keep the tree going in the intended direction. Keep in mind placing a wedge on the good side, opposite of the side lean, will lift your tree toward the lean and cause your direction to be off.

When dealing with large amounts of back lean and side lean, it is important to estimate the amount of lean. Wedging may be ineffective if the tree has more than 6 to 8 feet of back lean and more than 8 feet of a side lean (species-depending).

Another option is using a hydraulic jack to lift the tree. There are many different types of jacks that could be used, such as a tree jack to even a bottle jack. A proper slot must be removed from the tree to allow for the jack to be inserted.

Pushing

When equipment is available, pushing a tree is a very effective method for dealing with back lean. The most important part of pushing a tree is the safety of the timber cutter. If the tree is small, it may be possible to push the tree, stump, and all. If not, a proper notch and hinge should still be used to control the direction of the fall. Once the machine is against the tree, the back cut may be made.

establish the hinge, and leave the trigger on the back. The timber cutter can then escape away from the tree and allow the feller-buncher to cut the trigger and push with the arch of the cutting head. Marking the outside of the tree where the trigger helps the operator line up with the cuts already made.

Pulling

Depending on the situation, a conventional back cut can be made, but keep in mind that the desired hinge thickness may not be reached before the tree starts moving. This could cause a tree to split or bust. A bore cut would allow the hinge to be set without the tree moving. A trigger should be left on the back side of the tree. Once everything is ready, the trigger is released, the timber cutter clears the area, and the machine begins pushing. Remember, the higher in the tree the machine can reach, the more push it has. A skidder or dozer blade cannot reach as high as a cutter or track hoe.

The machine mustn't push too fast or too hard. Pushing too low, fast, or hard could push the tree off the stump, severing the hinge wood. Without hinge wood, we cannot control our tree. Another very useful method for pushing back-leaning trees is with the feller-buncher. A large, back-leaning tree can be set up by the timber cutter. Place the notch, bore in to

Pulling the tree may be required when pushing is not an option. Placing a cable or bull rope in the tree will allow the machine to be a safe distance away and pull the tree in the desired direction. As with pushing, the higher in the tree the cable is, the more pull you have. The tree is still cut in the same manner, notch, hinge, and trigger. Once the cable is pulled tight, the timber cutter can make the cuts needed. When the "all good" signal is made, the timber cutter releases the trigger and escapes from the tree. The cable is pulled, and the tree falls in the desired direction. When dealing with heavy side lean, it may be advised to put the cable at an angle that will help pull but also help guide the tree to maintain the direction without breaking to the side.

The most important part of dealing with heavy back and side-leaning trees is to only do what you are comfortable doing. It is better to walk away from a tree than to be carried away. Do not attempt to do something if you are not comfortable with it. Step back, re-assess it, and ask for help if needed. When using equipment to help deal with problem trees, it is always good for the operator and the timber cutter to work well together. If the team cannot come to a safe solution, walk away! There is not a tree out there that is worth a life!