The Japanese approach to nature is awe inspiring particularly in the way that they manage and prune trees. It allows for the creation of visual imagery that is unsurpassed in designed western landscapes today. One of the most intriguing techniques observed during a trip to Japan, was a range of tree propping techniques that I found in some cases quite unique and useful in the context of bonsai too.
One technique was to support the branches with a single upright wooden pole with a piece of wood or metal attached to the top that was strapped to the branch to hold it in place by a straw like string. This seemed to allow for an increased development in branch length well in excess of that which would naturally be attained. This was due to the weight of the branch being supported, thus the tree development was not hindered by needing to provide structural support to the branch and could grow horizontally. This produces amazing feats of elongated branches, often referred to as ‘welcome branches’ where they extend can over gates, entrances or doorways. A deviation from the single prop was the use of multiple single props supporting an entire crown creating a whole new aesthetic, which was fabulous to see.
A second technique seen was that of the ‘A’ frame design which was used to support single branches as well as whole trees in some instances. This was a simple structure, usually made from wood which acted as a prop to prevent a tree from leaning further, but allowing for the retention of perhaps trees that otherwise may have fallen naturally. Not all the props were vertical, some were at a slant, depending on which part of the branch or trunk they were supporting. These props were also used to artificially create the effect of a leaning tree, making a shape or form required for the setting of the landscape within the garden.
A third and more intricate technique, involved creating a framework upon which a tree branch is grown and tied into, a bit like a raft upon which the branch rests and grows. An extreme example of this technique was to be found at the Golden Temple gardens in Kyoto where one branch was being trained in a flattened form but also propped at the same time at a 450 angle. Wisteria was commonly subjected to the same management to provide shade and beauty.
To reduce the bark damage from rubbing on the props, what seemed to be straw pads were used either underneath, or round all round the branches, to act as cushions. Whole trunks of trees were also observed, covered completely with straw matting or bamboo mating which aided in keeping in warmth during the cold months as well as a decorative feature for the trees during the Cherry Blossom season.
The majority of trees that were being propped were pines; a notable example was a 300 year old Japanese black pine (Pinus thunbergii) in a garden in Tokyo which was vast in stature, spread and certainly majestic. There were multiple props underneath each branch as well as along each branch allowing for significant branch extensions.
The Japanese Black pine in itself is a magnificent tree with a distinct twisting branching habit, dark gnarly bark with long stout twisted pairs of needles. This tree is highly revered in Japan and being able to see mature specimens within the stunning gardens is amazing. The Japanese White Pine (Pinus parviflora) which is 5 needle pine with a blue-white line along the needles is another favourite pine used for training and shaping. In addition, the red pine (Pinus densiflora), which is another two needle pine that was also propped and the red bark not unlike the Scots pine was displayed to its full advantage by being propped at acute angles.
The Japanese seem to have a technique for dealing with all extremes of weather when it comes to trees. In areas like Kanazawa where there is heavy snow fall, rope structures are erected over the trees and are called yuki-zuri. They consist of straw strings that are rigged up over the whole tree canopy of pine trees as a countermeasure against snow. They create a pyramid shape which allows the snow to disperse as opposed to weigh down the branches to help preserve the branching structure of the trees.
Examples of most of the above techniques can be seen throughout the UK but not as common place as it is in Japan. The Major Oak in Sherwood Forest is a well known example of a propped tree and a second is an Indian bean tree in Victoria Embankment gardens that has metal props with ‘U’ shaped attachments to reduce bark rubbing.
Propping trees in the UK is less about altering the natural shape of the tree but providing support to a weak branch or trunk. In Japan propping is used for a wide range of reasons, the majority of which are to create a particular style or form from shaping the tree and less about preventing a branch from failing. Often starting from a very young age and continuing on well into the mature life of the tree. The majority of trees with limbs propped now rely on the props due to their elongated forms which would not be able to be supported naturally by the trees, if removed. This can be seen by some as unnatural or others as an art form, and I can certainly say that it is worth a visit to see it up close to make up your own mind.
With the above in mind, some of these techniques are transferable to bonsai if not all of them and recently on a workshop learning about Niwaki we got to have a go at some of the techniques for altering the branch structure of trees using string. For the majority wire is used in bonsai but more frequently I have now observed guying with the use of fishing line which is less obtrusive to help secure a branch in the correct position. For larger bonsai trees branches can also be weight down with wire or string with a weight attached to gently pull the branch into position. If you are looking to use some of these techniques for bonsai it is important to add cambium and bark savers around the branches to avoid the wire or string cutting in. This can be in the form of plastic tubing or rubber or even a textile wrap just to prevent bark damage.