21/06/2019 • ВыращиваниеPlanting plan and training systems of the hazelnut tree

The planting of a new hazelnut grove is an operation to which particular attention must be paid, in this phase, choices that could affect the entire production and economic cycle of the hazelnut grove are made.

The low production of some hazelnut groves, diseases such as root asphyxia, root rot, are the direct result of poorly executed works carried out during the planting layout of the hazelnut grove.

What is a “planting plan”?

The planting plan, in arboriculture, is the geometrical arrangement of the plants, with relative distances, set in a ligneous crop.

In modern arboriculture, the planting plan is generally set with geometrical criteria, distributing the plants in parallel alignment, called line or row, separated by rectangular strips called spacings.

The geometrical arrangement is important because: 

1. it make homogeneous the distribution of resources in terms of lighting, nutrients and water availability, in order to optimize the degree of resource exploitation and the degree of intraspecific competition between plants;
2. it rationalizes the execution of the cultivation operations, with particular reference to those carried out mechanically.

What are the most widespread planting plans in the hazelnut tree cultivation and the factors of chosen?

The most widespread planting plans are:

• 5×5 m (600 plants/hectare)
• 6×4 m (417 plants/hectare)
• 6×5 m (333 plants/hectare)
• 6×6 m (278 plants/hectare)

The choice of the planting plan is linked to various factors:

• the soil fertility
• the training system chosen
• the possibility of carry out irrigations
• the necessity of use machineries, such as self-propelled machines for the mechanical harvesting of hazelnuts 

Planting arrangement square (Figure 1 – Illustration A) or rectangular (Figure 1 – Illustration B): the plants are placed on the corners of a square or a rectangle.

Planting arrangement in quincunx (Figure 1 – Illustration C): the plants are placed at the vertices of an isosceles triangle and placed in the field in the same position as the boxes, of the same colour, of the checkerboard of the game of checkers.

The last arrangement proposed is preferable in the hilly areas because it reduces the risk of surface runoff of water and landslides. 

The 5×5 planting plan is used in less fertile soils instead the 6×6 is used in the more fertile ones. Nowadays, thanks to the mechanization of many cultivation practices, such as mechanical pruning and harvesting, the distances between rows have increased.

Training systems of the hazelnut tree

The hazelnut tree, once planted, can be grown as bush, bushy vase and Alberello training system.

Bush training system

The bush shape recalls the natural habit of the plant and in the case of broken branches (for snow, wind or fungal attacks) it allows the recovery through the choice of a bud born from the plant’s stump.

The multi-stem trunk (3 o 6 branches) makes the operation of suckers’ management and hazelnut picking more difficult.

The bush shape is the most suitable in dry cultivation (without irrigation) and in high altitude area where the snowfall is plentiful.

It is characteristics of the hazelnut groves grown in Piedmont and, in particular in the Alta Langa.

Bushy-vase shape

It is a system planted 30-40 cm above the ground.

The Astone (young plant that that can derived from grafting or can be cultivated from seed) planted in autumn is pollarded at 30-40 cm.

The following year, after choosing 4-5 vigorous branches properly oriented, we give shape to the vase.

This allows, as opposed to the bush training system, to easily carry out the operations of suckering and cleaning at the base of the plant.

Given the presence of a single trunk (stem) and the more contained foliage, the cultivation operations carried out mechanically and the treatments with pesticides are facilitated.

In the event of breakage of the main trunk, it will be necessary to replace the entire plant.

The bushy vase training system is most suitable for fertile soils and where it is possible to irrigate.

Alberello shape

It is a mono-stem training system (single trunk) from which depart 3-4 branches.

The Astone is pollarded at 70-80 cm from the ground and here the best-oriented buds that will form the Alberello-shape are chosen.

It requires more time and manpower for the pruning operations than the other training system previously illustrated. It is suitable for flat areas and for fertile soils where it is possible to irrigate.