Hi Bren,
[b:c6ce39a2c6]1) What is a 'leader'? I have the impression it is the branch that grows up out of the chopped off trunk, rather than straight out like the others.[/b:c6ce39a2c6]
The 'leader' is the branch designated to form the apex of the tree. The tree and the hobbyist may have different ideas about which branch is the leader, so a tree placed in the ground can't be neglected for long. In a cascade style bonsai the leader might actually point downwards, but it is the branch that will form the eventual extension of the trunk.
[b:c6ce39a2c6]2) If, as Brent Walston says in his article[/b:c6ce39a2c6]
'Developing Large Trunks for Bonsai'[b:c6ce39a2c6], it is best to grow a tree for 10 years or so before chopping its trunk and moving it to a Bonsai pot, won't this result in just a large trunk with a small branch growing out the top, i.e out of proportion, a tree that bears no resemblance to itself in the wild? To have an idea of what i mean, check out the picture of his chopped [/b:c6ce39a2c6]
Zelkova in training.
I have not read the article recently, but my memory of it (and in reviewing it again briefly today) is that it is an article on how to develop large trunks for bonsai, and is not meant to suggest that all bonsai must have large trunks, nor that trees should be grown for 10 years before they are cut and immediately potted up. The technique he describes in field training plants for bonsai involves letting them grow until the trunk base approaches the [i:c6ce39a2c6]desired[/i:c6ce39a2c6] thickness, then cutting again (still in the field) and allowing the trunk to develop still more, both healing the wounds and creating movement and taper in the trunk. This process is repeated over time, and depending on the caliper of trunk desired, this could go on for years.
At some point the tree is lifted and more controlled refinement takes place (that is the Zelkova's stage). Then, according to this approach, the tree is potted only when the structure of the trunk and perhaps the main branches is defined.
[b:c6ce39a2c6]3) Is it also true that a tree's trunk will thicken very little in a Bonsai pot? If this is true, than as a beginner I have wasted a lot of my time as a lot of my young trees and cuttings are in Bonsai pots already. [/b:c6ce39a2c6]
If your ultimate goal is a thick-trunked tree, you will not be advancing the cause much in a bonsai pot. Bonsai pots are good for refinement and display, or moving trees around. Containers, because they limit the spread of the root system, aren't particularly well-suited to developing wood, and the drainage, frankly, is lousy.
Considering whether your time is wasted doing anything really depends on your goals. (I know a few people who would suggest that this entire hobby consists of wasting time
) In any case, in the process of cultivating trees in pots, you will learn more about their needs and how to maintain and refine them, so I don't see it as wasted.
Not all bonsai have or need thick trunks. If you consider the hibiscus that Walter posted in the Gallery a while back, you'll see a tree that is very well developed, but could hardly be considered to have a massive trunk. Putting that plant in the ground at this point would ruin it utterly, as new shoots would form from the branches in explosive growth, causing them to thicken and all refinement would be lost.
Hope this helps!
Regards,
Matt