Arboricultural terminology – How to understand by the tree experts.
Sometimes a single word or a phrase can be very useful in describing something complicated.
Arboriculture (tree work) is full of these phrases.
When we are out on a tree site, we do our best to describe our intentions in simple language that can be easily understood by our clients.
However, we are not perfect and sometimes technical terms can slip out.
Or words fail us, and we instantly result to the one word or phrase that we know explains what we mean.
As a client, having knowledge of Arboricultural terminology can be very useful.
It will help you achieve the exact result you want for your trees.
This Blog post is designed to shed some light on some of the common arboricultural terms.
Arboricultural terms that you might hear when speaking to an arborist or see when reading an arborists report.
To list all the terms used in Arboriculture would take several pages.
So instead we are listing some of the more commonly used ones and will include links to resources that list them all at the end.
What is Crown Thin?
The removal of a percentage of smaller branches, ideally in the outer canopy, to produce a uniform density of foliage around an evenly spaced branch structure.
Material should be removed throughout the tree and no more than 30% during one growing season.
What is Crown Lift or Crown Raising?
The removal of the lowest branches.
Crown lifting on mature trees should be restricted to secondary branches or shortening of primary branches rather than leaving large wounds on the trunk.
What is Crown Reduction?
The selective reduction in height and/or spread of a tree’s crown.
Crown reduction should retain the main framework of the crown and a significant proportion of the leaf bearing structure.
Ideally crown reduction cuts should be as small as possible and reductions should be specified by actual measurement or percentage.
What is epicormic tree growth?
Shoots that arise from dormant or adventitious buds that occur on stems and branches and on suckers produced from the base of trees.
What are Co-dominant stems?
A situation where a tree has two or more stems which are of equal diameter and relative amounts of leaf area.
This can often pose a significant defect in a trees structure.
What is a tree Decline?
A tree exhibiting a lack of vitality such as reduced leaf size, colour, or density.
What is Formative pruning?
Minor tree pruning during the early years of a tree’s growth. To establish the desired form and or to correct defects or weaknesses that may affect structure in later life.
What are Fungi or Fruiting bodies?
A member of the plant kingdom that may colonise living or dead tissues of a tree or form beneficial relationships with the roots.
The fruiting body is the spore bearing, reproductive structure of that fungus.
Each colonisation must be considered in detail by a competent tree expert. To determine the long-term implications of tree health and structure when considered alongside the tree species, site usage etc.
What is Lopping and Topping a tree?
Lopping trees refers to the removal of large side branches. (The making of vertical cuts) and topping refers to the removal of large portions of the crown of the tree.
This is the making of horizontal cuts, generally through the main stems.
Often used to describe crude, heavy-handed or inappropriate pruning.
Pollard: the initial removal of the top of a young tree at a prescribed height to encourage multi stem branching from that point.
It is traditionally used for fodder, firewood, or poles. Once started, it should be repeated on a cyclical basis always retaining the initial pollard point.
Retrenchment pruning: A form of reduction intended to encourage development of lower shoots and emulate the natural process of tree aging.
This can be used to manage large, old trees in the urban environment.
Vigor: the capacity to resist strain. It is a genetic factor and a potential force against any threats to survive.
Links to the sources where I took theses definitions from can be found below.
For anyone wishing to learn more they have extensive lists of all arboricultural terminology.
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Rossy and the Team.
Rossy | 021 508 806 | treecareauckland.co.nz