Leaf size reduction, let's do this. Leaf reduction comes from fine ramification. That's it, this might be my shortest post yet.
Ramification is when a branch grows, then a secondary branch grows on that, then another branch grow on the secondary branch. A key point is that the growing branch remains smaller than the branch it grew on. The rule is that the finer the branch the finer the leaf size. There are limits to how small the leaf can grow, and not all trees will reduce in leaf size.
Some trees will only grow branches where leaves grow. Some others will grow branches anywhere on trunks and branches. Having said that I have noticed that for some species if I cut the branch short before it is lignified (before the branch becomes woody), the first pair of leaves of the secondary branches will grow very small.
When thever secondary branch gets to a desired thickness prune it shorter than the main branch. Keep doing this with the third and fourth branches. Cut each branch length smaller than the branch it grew from or until you get the desired results. How short should you cut them? Well, People will tell you many things. It depends on what shape your giving the tree, and the branch you are working on. The best thing to do is to do and learn.
Leaves are solar panels. The tree needs a minimum amount of solar panel surface area to survive. As you reduce the size of the leaves the tree will produce more leaves to compensate. A great example of this is ficus benghalensis. The leaves of this tree are bigger than a human hand. Yet, the size of the leaf can be reduced greatly on a bonsai through ramification.
|Reduced leaf size Chinese elm|
This is the same species of tree as in the picture above. The seedling is about three months old and has no ramification. If you notice, the leaves are bigger than the leaves of the bonsai that has branch ramification. Look at the base of the seedlings pot. There are some leaves there that are the same size as the ones on the refined bonsai. I thought that it was interesting to see that. I have a theory that leaves can be reduced to about the same size as the plants first true leaves. Ill have to keep making observations though.
|Ficus microcarpa at the National Bonsai and Penjing Museum|
This was a simplified version of leaf reduction and ramification. The basic principles are there. Cheers.