Cut Paste – The Plot Thickens

buy modafinil in usa Last month you were left standing back and admiring your handiwork.  You had purchased a large bush and had styled it into a potential bonsai masterpiece.  In the process, you had removed a large branch, carefully trimmed the ragged edges of the cut, and then sealed the cut with cut paste to keep the raw wood moist in order to encourage callus formation.  Now all you had to do was to wait for the cut to heal over to completely hide the place where the branch was removed. However, the story does not always end there.

http://vintagegoodness.com/2016/09/ In some species of trees, large cuts heal over relatively quickly.  For example, trident maples can heal cuts as large as an inch or more in diameter in as little as a couple of years.  During all this time the raw wood exposed by the cut must be kept sealed with cut paste. But once the callus completely covers the raw wood the cut paste is no longer needed.  If the callus is growing slowly or has stopped growing, sometimes lightly trimming the inside edge of the callus with a sharp knife can stimulate growth. The sad fact is that some species of trees such as oaks and hornbeams heal very slowly if at all, and raw wood is exposed permanently.

The presence of a lot of water and air, with some help from friendly bacteria, causes the cellular stickem which holds wood fibers together to become unstuck, and the wood dissolves into mush.  This process affects all wood, although the process works faster in some cases than others.  Examples of the two extremes are teak, which endures for many decades soaking wet in  hot humid climates in South East Asia, and oak, which is a very hard and tough wood but can extensively decay in as little as two or three years when kept wet.  The objective for bonsai artists is to keep the raw wood of these trees sealed to keep the excessive moisture and air out.

Cut paste can be used to protect the wood, but better alternatives are products which penetrate the wood and then cure to a permanent water impervious seal.  One such product is Wood Hardener made by the Minwax Company.  PC-Petrifier is a newer wood hardening product which is water-based.  Both of these products are widely available in hardware stores.

The consequences of wood decaying into mush can vary depending on your vision of the finished tree.  Most deciduous trees emphasize the bark and the line of the trunk. A large scar resulting from the decaying process would greatly detract from the tree.  On the other hand, on a conifer with lots of jins and shari, there is a possibility that decaying wood where a branch was removed could add to the look of the tree.  In this case, the decay could be allowed to proceed and then at some point, the decayed wood would be removed and the remaining wood would be sealed to stop the process.  This technique involves a bit of brinksmanship and is not widely practiced in the United States.  However, it is practiced occasionally in European bonsai circles.  In fact, there are advocates to letting all the wood of the tree decay which leaves a hollow core.

Needless to say, using the decay process to style a tree has problems, the biggest of which is that you really have no control of the process.  You cannot direct with confidence where the decay will go, nor can you stop the decay just at the right point to prevent the remainder of the tree from collapsing. The best procedure by far is to carefully protect exposed wood to prevent the decay process from starting.  If you want to enlarge the place where a branch was removed, best to carve the raw wood and then properly seal the cut.

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