Page 148 - Tài liệu cây cảnh Bonsai4me Bonsai Basics

With most forms, the trunk must taper from its thinnest point at the apex to

its widest point at its base. It is preferable for the trunk to taper as gradually as
possible.
The trunk must not have inverse taper; that is to say the base of the trunk
should not be thinner than any other point of the trunk.
Half to two-thirds of the trunk should be visible from the front to reveal the
structure of the trunk.
Trunks with any slope in any direction should also slope at ground level.
Grafted trunks should not be apparent unless inspected very closely.
Informal forms should preferably have turns or bends that diminish in size
and length as the eye travels from trunk base to apex.
Trunks should be cleaned of algae and moss.
Branches

Branches normally commence around one-third to half the height of the tree.
The first branch should be the thickest with the branches thinning in diameter
as they progress towards the apex.
The first branch should normally point towards the left or the right when the
tree is viewed from the front.
No branch should lie directly above another.
No branch should cross another.
All branches should exhibit taper from trunk to tip.
All branches should be shaped similarly to each other and should reflect the
movement (or lack of) in the trunk.
Normally, only branches in the top third of the tree should point directly
forwards, towards the viewer.

No two branches should appear from the same place on the trunk (bar
branches).
No two branches should appear to be at the same height.
No branches should cross the trunk as seen from the front.
Tree outline
The trees' outline is normally roughly triangular.
Depending on individual species the apex should be triangular or rounded
but not pointed.
Group plantings or trees with multiple trunk forms should have an overall
triangular outline, this triangular shape should not be symmetrical.
In some groups, a dominant tree can disturb the overall triangular shape.

Foliage, flowers and fruit
Dead or diseased leaves should be removed.