Too many people seem to believe a tree planted straight from the nursery can simply be left to its own devices, which is far from the truth.

FEW people would think of depositing a young baby at the side of the road and saying ‘goodbye, you are on your own’.

The reasons are fairly obvious and the forthcoming analogy is perhaps a little extreme, but isn’t that what is constantly being done to young trees when planted out into the harsh urban environment? They come fresh from the nursery, where they have been pampered and cossetted for their entire lives, to be deposited in the ground and, other than sporadic watering, left to get on with it.

Standard trees from the nursery will be anything from 7–10 years old at the time of dispatch and will represent species which have the potential to live and grow for anything from 60 to 200 years or more. They are mere infants and many will still be in their nappies when compared to the age they may live to.

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The branching system created on the nursery will be at best temporary and prepared, largely for the nurseries’ convenience, with a series of pruning operations, designed largely to ensure that the central leader of the tree is straight, dominant and capable of eventually supporting a strong and balanced healthy crown.

Most standard nursery trees are supplied with a clear stem of approximately 1.8 metres. Why 1.8 metres is a mystery, as this height would appear to have no real purpose for the tree as it hopefully continues to develop in the landscape after planting. Clearance for streets and highways is approximately 2.5 metres, although there are variations on this. This means that almost a metre of the carefully developed nursery branching system will be redundant and pruned out at some stage – or perhaps not, as will be seen.

Over the years I have seen many young trees or many species leave the nursery, many I have tracked to their place of planting and in some cases tracked their development. It is rare to find that there is a formative or structural pruning programme in place. It seems to be assumed that the tree from the nursery is the finished product and can be left to its own devices.

Forestry Journal:

The nursery tree is a creation made on the nursery. It is a rarity to find the model of the nursery tree in nature, where seedlings develop and the growing tree reacts to its immediate environment, creating a correspondingly adapted branching system and supportive trunk which may be anything but straight. Such random and environmentally influenced growth would not be acceptable in the urban environment, where uniformity and structural soundness are of paramount importance and where stem clearance is an integral part of life next to the road.

From its infancy on the nursery, the crown of the tree has been worked, with branches subordinated or removed to ensure a strong, straight and well-developed central leading stem is produced. It is this stem, later to be called trunk, which will carry the tree’s permanent structural branching system and many of the lower branches will be obsolete and have to be removed at some stage.

Yet often it can be seen that lower branches have been left and allowed to develop so that when pruning is eventually carried out, what could once have been achieved with a pair of secateurs now has to be tackled with a bow saw or even a chainsaw, with the resultant larger wounding.

In the crown it can be even worse, with the nursery crown retained but left unworked after planting. The carefully constructed leader often gradually, as the tree develops, disappears with competing and co-dominant shoots developing. Gradually the leader is compromised and the potential for it to be the basis on which a well-balanced and structurally sound crown can be developed disappears.

Yet this can be avoided if early pruning is carried out in the formative years after planting. Careful work with secateurs and long arm pruners can continue the work, started on the nursery, of subordinating competitive and co-dominant branches, continued leader definition and the development of a well-balanced crown.

The question also has to be asked as to how many of the structural faults and weaknesses which have to be corrected or rectified as the tree reaches youth or middle age with climbing and chainsaw work could be tackled with the judicious use of secateurs of long armed pruners when the tree was young.

It is a challenge to walk among trees in the urban environment and note the many potential weaknesses and problems in trees’ crowns. The number of times co-dominant branches can be seen with developing bark inclusion apparent, the number of times there are co-dominant leaders, the number of times where lateral branches have made the decision to become the leader themselves, the number of times where young branches have continued to develop into the crown and the number of times each of these could have been corrected at an early stage.

The process should begin at planting with leader definition ensured and competing and co-dominant laterals subordinated or removed. This process should be continued as the young tree develops until the permanent structural crown is in place.

This process will be different from species to species, but the challenge is the same – how to retain the strong leading stem/trunk throughout the centre of the tree, how to subordinate lateral branches and how to ensure that major works at a later stage of the tree’s life can be avoided.

Forestry Journal:

Winter is approaching and despite a late leaf fall, the structural canopies are becoming clearly visible and clearly defined against the skyline. When travelling, take a look at the bare branches, look for distortions in the crown, look for co-dominant leaders and assess how many of the problems inevitably discovered could have been corrected when the baby came from the nursery and continued its development in the landscape.

I think you will be surprised, maybe horrified, but I suspect that once you start looking you will never stop and maybe, just maybe, either buy a set of secateurs or polish and sharpen those that are not often used.