It is not the purpose of this Journal to teach people how to do bonsai. The primary purpose of the Journal is to tell how bonsai became a central component of The North Carolina Arboretum's identity, while along the way recording the known history of the various specimens that make up the Arboretum's bonsai collection. Still, there is frequent enough opportunity to delve into the "How To" aspect. The Arboretum's bonsai collection includes a significant number of homegrown trees — bonsai that originated with us and have been developed here, as well as some trees that are currently still in the process of being developed — which is yet another characteristic that sets us apart from most other public collections. In that regard, documenting the various stages of building a bonsai specimen is a means by which it can be better understood how many of the Arboretum's bonsai came to be what they are.

There was never any conscious decision at the start that the trident maple (Acer buergerianum) featured in this entry should serve as a case study in bonsai development. It happened that this particular maple, which had been planted in the ground as a very young tree in order to build up a sizable trunk, was ready for harvesting right at the time when Curator's Journal was first starting out. The process of collecting such a ground-grown bonsai-in-training seemed like reasonable fodder for a bonsai blog. Because the Arboretum has several capable young videographers on staff, it was decided that making a video showing how the maple was removed from the ground and introduced to a container would be an interesting alternative to writing about it. That video was posted to the Journal early in year one and can be viewed here. The following year, when it was time to do some serious first shaping of the maple, it turned out to be the subject of another Journal entry, which can be revisited here. Then, earlier this year, the same maple afforded an opportunity to illustrate the late winter/early spring work done on a tree in development to be a bonsai. That entry can be found here.

The time of this present writing coincides with the final week of spring. The developing trident maple has received no attention since being prepared for spring growth back in the first week of March. Other little trees, more fully developed and presentable as bonsai, have, in the same span of time, already been pruned two or even three times. Developed specimens require more constant attention in order to maintain their presentability. Trees in development fall in line behind presentable specimens when it comes to the frequency of attention they receive, mostly because of time constraints. As a tree in training draws closer to becoming a presentable specimen, it requires ever more frequent maintenance of its growth. Last year this same maple went the entire growing season without being pruned, not because it wouldn't have benefited from the attention, but because it could more easily absorb the neglect without incurring negative results. In effect, the tree was kept in a sort of holding pattern. Now the time has come to pick up the pace.

To begin, this was the appearance of the trident maple before the current work session:

The first step was to wade into the rank overgrowth of shoots and foliage and bring the crown back under control. Almost all extending shoots were pruned back to a single pair of new leaves. Exceptions were made for the weakest shoots, which for the moment were allowed to remain intact. Here is the effect of this initial move, seen in quarter-turn views of the tree:

The crown of the tree is now more compact and appears more tidy, and is in better proportional relationship to the trunk under it. Close inspection, however, reveals a great degree of structural chaos lurking beneath the foliage:

The pruning done in early March carefully organized the branch structure of the crown, setting up the tree for a new growing season. The springtime surge of growth in plants is a powerful phenomenon! Shoots explode outward with great force in an effort to project themselves as far as possible, like a sprinter coming out of the starting block. With a young maple such as this, the new shoots not only extend vigorously but also break out in great abundance. A single cut end of an existing branch can yield a half dozen or more new points of growth emerging from the area of the wound. This is a feature of pruning when correctly done — taking away from the plant prompts it to produce more growth, a critical component of the bonsai paradigm.

Follow-up is necessary. The plethora of new shoots and accompanying leaves produces an agreeable look of fullness at first, but if all those shoots are allowed to remain the result will not be good. Before long those intersections with so many divergent points of growth will begin to swell and become unsightly. The various shoots and their accompanying leaves will compete for light, with some succeeding and others dying out. It is incumbent upon the grower to visit each of these intersections before any of this occurs to whittle down the host of new shoots, typically leaving only two at each juncture to carry on in their development. This is painstaking work because the branches in question are small and the intersections are crowded, with many of the new shoots being no greater in diameter than a piece of string.

The choice of which shoots to leave and which to remove might be done arbitrarily, but again, the results of such an approach will not likely be good. In the relationship between the bonsai grower and the plant that is being shaped, the plant produces the stuff from which the bonsai will be made. The grower then decides the eventual shape of the bonsai by editing and directing what the plant produces. Every choice the grower makes has some effect. Good design depends on good choices, and choices have a better chance of being good if they are done with thoughtful, well-informed intention. Decisions made randomly produce random results, and good luck with that.

Here are a couple examples of crowded branch intersections after the thinning out work has been done:

Here are images of the upper portion of the crown, comparing its appearance after the initial pushing back to one set of new leaves per shoot with how it looks following the careful selection of which shoots are retained for future development: