Page 80 - Tài liệu cây cảnh Bonsai4me Bonsai Basics

problems that may exist;

Remove any dead, decayed or injured roots to prevent or cure problems with
root rot. Dead or rotted roots will be black, slimy and their outer bark will slip
easily from the root itself; severely rotted roots will be entirely hollow and
crumble away.
(It should be noted that Larix/Larch species naturally have roots that during
their dormant period resemble a severe case of root rot, care must be taken not to
remove a healthy Larch rootsystem!)

After excess circling roots have been removed; check the rootball for faults,
particularly around the area of the nebari.

If the rootball has become excessively dense, make wedge shaped cuts into
the remaining rootmass. This is only necessary on a well-developed, densely
packed rootball and ensures that fresh soil is applied to the centre of the
rootmass and that water is able to permeate. Try to encourage the development
of the rootball each time the tree is repotted. The trunk should have roots
spreading radially from around its base; roots that grow upwards or recurve from
the base (nebari) are considered ugly. Strong, thick, downward growing roots
should be removed so that the rootball is flat and can be fitted into the pot.
Downward growing roots left without pruning will start to lift the tree out of the
pot.
Any other thick or straight roots should also be pruned back to a point where
there are fine roots branching out. Thick or straight roots tend to rob the vigour

of smaller finer growth. At all times when pruning back such roots, it is
important that they are inspect carefully to ensure that their removal will not
reduce the rootmass to a level where it cannot support the tree. Thick roots