Carving a Tree Trunk
Carving the trunk of a tree can be a trip into the twilight zone. More times than not the stump exists because the tree died, and if the tree died it was probably diseased, and if that is the case it is very likely to have suffered some sort of physical degradation. Whether you own the tree or you're the one going to carve it, there are some things you should be aware of which could quite possibly save you a great deal time, money and frustration. The following information may aid in making the determination as to whether or not a standing tree trunk has the necessary " soundness" to be used in making a sculpture.
At the point we begin to remove wood from the tree trunk, we begin our odyssey into what could become a proverbial money pit. Certainly if you're the carver "time is money", and the meter should be running. If you are the owner and you have hired someone to carve this for you, you must get an estimate of what it would cost to continue and make the hard decision of whether or not to walk away from the project. If you go ahead with it, you may be investing in something that will never bear fruit. That's the downside. If, on the other hand, you are the carver employed to do the work you may be faced with the decision of turning down the job, but at the very least you should advise your customer of the monetary risk involved should you continue. For these reasons it is well to gather and use all available knowledge we can obtain about the tree trunk before the actual carving begins.
 |
|
|
|
|
|
|
|
|
|
|
 |
||||||||||
|
I N S P E C T I O N T I M E |
||||||||||
|
Lets start with some basic assumptions |
||||||||||
|
Given: Most tree trunks that people want carved exist in the yard surrounding their homes or in public places Given: Most people don't cut down healthy trees in their yards or public places to make sculptures out of them. Given: Most people want their sculpture made from a tree which has died. Given: The tree died for a reason! That reason may have rendered the wood unfeasible to carve. |
||||||||||
 |
||||||||||
|
Just as a doctor begins an examination by asking questions, the ultimate decision to determine if a tree trunk is a good candidate for becoming a wood sculpture should begin here. Some essentials should include.
Answers to just these three can provide a wealth of information. Perhaps most important is the first, How the tree died. |
||||||||||
|
Illus. 1 Finding a tree trunk with all the inherent defects which might be found in any one of them, would be an inpossibility. So I drew one. Above, I have superimposed it in this rather placid scene to simulate a natural environment that it might be carved in. |
||||||||||
Death by Trauma
Storm Damage
I won't begin to attempt to cover all the reasons a tree dies, except to generalize. In general terms I can divide tree death into two categories, which are basically trauma and stress. Trauma such as a lightning strike will in most cases cause premature death, or sudden death, while stress, sometimes just generated by old age, will generally take years before the tree finally succumbs. The cause of a trees death may seem inconsequential to its carvability, but as an example to support the importance of this information, take the case of storm damaged tree.
One of the great characteristics of wood is it's flexibility. Closely coupled with flexibility is "memory". Memory denotes the ability of any material to return to its natural state once it has been deformed or flexed. This is very apparent in wood when it is used as a bow (for shooting arrows) or a bat as used in baseball. Wood will generally bounce back to its original position as long as the wood fiber itself maintains structural integrity (does not break). Just when structural integrity has been breached is not always apparent however. Oddly the flexibility trait of wood itself can mask the fact that a piece of it has experienced structural degradation. In the case of a storm damaged tree, the same flexibility can actually mask the fact that the trunk has been fractured. So much so that it may be impossible to determine.
Illus. 2 The drawing below illustrates the special kind of damage that is done to the wood in a tree which has been damaged due to extreme pressures which extend it beyond its endurance.
In this example beginning with the tree A. at far left, under no stress, makes apparent the bend occurring in tree B. due to pressures as might be applied by extreme wind or perhaps ice accumulation. Extended beyond the breaking point the damage is apparent in tree C. But what if the tree doesn't break as in C.? It is all to frequent that the the tree, when exposed to such a force, does not break but remains resilient enough within its flexibility to right itself even though it may have suffered fracture. In point of fact, this can happen to many trees that do not die but actually go on growing and live a long healthy life. When these trees are eventually cut down and chance should provide them for carving, only the carver will end up finding this defect. He discovers the sad truth only when the sculpture is begun, as pieces fragment rendering the wood useless to his purpose.
If there is any indication that a tree has been storm damaged in this manner it should be totally avoided for the making of sculpture not to mention cut up for lumber. Many more times than not the tops of trees are sheared off due to high wind leaving a stump that looks sound. Again it should come with a sign on it that says "Proceed with Carving at Your Own Risk". Personally I would never even consider it.
On the other hand, if you are not sure of the stump or trunk, you might at the very least give it this test before proceeding. Most trees which have lost their tops due to a storm will have the resultant spiny protrusions extending from the end of the stump. If the tree was living and healthy the broken area will resemble a bundle of straws. But if tree trimmers or the power company or home owner has trimmed this portion off, the unaware carver, who may also not know the history of the storm in the area, might invest a great deal of time before he realizes this defect. Some of his anguish may be alleviated by having the customer or himself take an additional two to three inch slice from the top of the trunk. That slice is allowed to dry out for a period of at least two weeks. If shakes are inherent in the stump they should become visible within that period. If shakes become visible, do not use the wood for carving. Don't even try to use the part which doesn't have any visible shakes. Again, if I am certain that a tree has been fractured by storm or by improper felling, I will not touch it for carving wood. Shakes are perhaps one of the more insidious defects to a tree trunk due to the difficulty in detection coupled with their potential for disaster if a sculpture is attempted in their presence.
Illus. 3 At right, Simulated cross section of a tree trunk.
Wind Shakes as shown at right are created virtually from the shaking the tree receives from whipping back and forth in high wind. They are very damaging to the wood since they usually run the entire length of the trunk. They are generally ragged in appearance and almost always run tangentially to the center of the tree. Felling Shakes are shakes which are caused when a tree is cut down, usually when the tree strikes another stump or across another tree. They are similar in appearance to wind Shakes.
Lightning Strike
A lightening strike could be considered as a storm damaged tree except that it seldom damages the tree at least in terms of usable wood. And it doesn't always lead to the sudden death of a tree though it many times does. If the tree continues to live, then that is when it can be very damaging to the wood. The lightning usually rips down the length of the trunk burning a strip down the exterior. It strips a section of bark throughout the length while rupturing and killing the cambium layer. Such a wound is slow to heal and may take years to do so. In the meantime the interior of the tree has been exposed which begins to decay. The decay ultimately contributes to the early death of the tree which by that time has rendered the wood useless for practically any purpose.
If all this is considered, a tree hit by lightning, killed or not, can be an excellent candidate for a sculpture material, providing the wood is used within a short time subsequent to the strike.
Slow Death- Stress Death
