Training Young Community Trees
What does that mean?
Why is it done?
- Training means pruning young trees for form during the
first few years of their existence.
- Good nursery stock already has had quite a bit of training by
the time it reaches the market. In fact, that is an important trait to
look for when you buy.
- Trees are trained
- to direct growth
- to correct structural weakness
- to adapt the tree to its human environment
- In the long run, a trained tree will be stronger, healthier, safer--and
cheaper to maintain.
- Early training is better because the extent of infection
from wounding depends greatly upon 1) the size of the wound, and 2) the
age of the tree. In general, the smaller the wound and the
younger the tree, the less decay will result.
Amur maple after being
trained for scaffold branches
How is it done?
- Select a single central leader if the young tree does
not have one, and prune out any competitors. One central leader, or stem,
is almost always preferable in street trees.
- Some species (such as many conifers) usually produce a single leader
and need no training, others (such as sugar maple) often produce multiple
leaders and need quite a bit; most species are in the middle, and do well
with moderate training.
- Select what will be the lowest permanent ("scaffold") branch,
and prune out nearby competitors. Choose a branch that 1) is
vigorous, and 2) has the right clearance.
- Remember that once a branch is formed at a given level, it never
gets any higher.
- Select and prune for other scaffolding branches.
- Choose vigorous branches less than half the size of the central
leader that are
- well spaced apart (at least 18" for large trees)
- well distributed around the trunk.
- Finally, make temporary branches by cutting back branches
you will not be keeping that are below or between the scaffolding branches.
When is it done?
- do not remove these branches for now, just reduce them
to a few buds
- the leaves on temporary branches produce food for the young tree,
and protect the young bark from the sun; they can be removed later when
- Don’t take off more than 25% of the leaves and buds at
any one time.
Where can I get more information?
- Prune nothing the first growing season after planting
except broken, rubbing, or misshapen branches. The transplanted tree needs
all its leaves to reestablish its roots.
- Many communities schedule the first training for the third year
after planting, a time when remulching can also be done
- Most species are best trained in late winter, though badly
resprouting species (such as lindens or crabapples) are better pruned soon
after leaves have fully expanded.
ISA, "Pruning Young
Trees." For other information, advice and help on this topic,
call offices of your State Urban Forestry Coordinator or University Extension
service, or visit urban forestry web sites.