What are tree cabling systems?     

“Tree cabling systems are connections between crown parts that are at risk of breaking off. They are to prevent one or more crown parts from breaking off or falling.” German Treecare Standard (ZTV Baumpflege)

English introduction video

cobra® tree cabling system

- the right system for every tree -

Basic questions


The same questions crop up time and time again if a tree is being restored to be safe for traffic and pedestrians using tree cabling systems:

  • Is dynamic or static tree cabling required?

  • Which breaking load is required?

  • Where should the tree cabling be installed?

  • What do I need for this?

Our answers

dynamic or static tree cabling


In most cases branches/stems are supported using dynamic cabling. This is installed as horizontally as possible and ideally as triangle cabling. This type of cabling supports all wind load directions.

Static cabling is only installed if a branch is cracked. This is also installed as horizontally as possible and as triangle cabling.

Wide branches or branches where cabling against side wind loads is not possible are secured using static support/load cabling. With this the tree cabling runs as vertically as possible and is not to prevent breakage but to prevent it from “falling to the ground” afterwards.

Recommended breaking load


As a rule, no complicated calculations or analysis are required here. In practice we rely on arborists’ decades of practical experience. The ZTV Baumpflege standard’s notes on breaking loads for crown bracing apply here.

German treecare standard (ZTV Baumpflege) note on calculating dynamic tree cabling systems:

Branch /System diameter 

(measured at the base at the time of installation)

Minimum breaking load

for the warranted service life, installed at least in 2/3of the branch/stem length to be cabled​

​up to 40 cm

​2,0 t (cobra 2t)

​over 40 and60 cm

​4,0 t (cobra 4t)

​over 60 cm and 80 cm

​8,0 t (cobra 8t)

​over 80 cm

​Special situations to be decided on a case-to-case basis

German treecare standard (ZTV Baumpflege) note on calculating static crown bracing and load/support cabling systems:

Double the values for tree cabling systems that are to keep part of a tree still or absorb permanent loads.

Recommended installation position and height

It is also recommended that the German treecare standard (ZTV Baumpflege) recommendations are followed here.

If the installation is on one level, then dynamic or static cabling is installed at least at 2/3 of the height of the branch to be cabled.

If the installation is on two levels (with split forks), then static cabling is installed at least at 1/4 of the height and dynamic cabling is installed in 2/3 of the branch to be cabled.

Our solutions


Application area:

  • Minimum breaking load: 2t (2.000 daN)

  • 12 years’ service life

  • Up to 40 cm branch ø as dynamic cabling

  • Up to 30 cm branch ø as static
    load/support cabling


Application area:

  • Minimum breaking load: 4t (4.000 daN)

  • 12 years’ service life

  • Up to 60 cm branch ø as dynamic cabling

  • Up to 40 cm branch ø as static cabling or load/support cabling

Application area:

  • Minimum breaking load: 8 t (8.000 daN)

  • 8 years’ service life

  • Up to 80 cm branch ø as dynamic cabling

  • Up to 60 cm branch ø as static cabling or load/support cabling

Up to 40 cm branch ø as static cabling or load/support cabling

More than 500,000 cobra crown bracing systems installed worldwide