Static and dynamic crown anchorages

Crown anchoring in trees is a technique used to improve the stability and susceptibility to fracture of a tree or crown part. By supporting or securing weak branches and reducing the freedom of movement between branches and trunk parts. This prevents breakage, or broken parts from falling and thus causing damage.

Crown anchoring is often used for valuable, historic or veteran trees. Where preservation is important. Or in situations where the risk of large falling branches poses a danger to people, property or the environment.

 

Anchoring branches from the crown or trunk parts can be done both statically and dynamically.

Where preference is usually given to dynamic crown anchorage. Because the secured parts (read branches and crown parts) can still move quite freely. And thus be able to achieve sufficient thickness growth. This makes them stronger, which is an advantage and you obviously want it.

 

 

 

Static crown anchorage in trees

Static crown anchoring uses rigid systems to attach parts of the tree to each other or to an external support point.

This type of anchoring significantly limits the natural movement of the tree or its crown parts.

You use static systems when direct and strong support is necessary. Such as stabilizing an almost split trunk or heavy one plaque sludge. Or supporting heavy, overhanging branches, which pose an immediate risk of tearing out.

Placing static crown anchors originated in the former “tree surgery”. Cables or steel shafts were often used between two or more large crown parts.

At that time it was not yet realized that the thickness growth of these parts decreased. Opposite without this static crown anchorage. Due to the static nature of this type of crown anchorage, the secured parts invest more in length growth. Instead of in thickness growth. As a result, the problem you wish to solve often unintentionally becomes larger, due to the greater moment forces that will act on the branch attachment (or armpit) that you wish to protect.

Later, to prevent this problem, dynamic crown anchors were created.

Note that old static crown anchors can only be replaced with new static crown anchors. And not by a dynamic crown anchor. The crown parts or branches have not grown enough in thickness for this in recent years.

 

 

Dynamic crown anchorage in trees

Dynamic crown anchorage, on the other hand, offers more flexibility and allows a certain degree of natural movement.

This method often uses flexible materials such as ropes or special bands that stretch under tension or pressure.

Dynamic systems are intended to support the tree in its natural growth and movements, which promotes the formation of stronger wood, due to the thickness growth that still takes place at a normal level. And the chance of breakage is greatly reduced.

This type of anchorage is suitable for supporting and securing branches and crown parts that need to be strengthened, but are still sufficiently juvenile.

 

 

Application of crown anchors

The choice between static and dynamic crown anchorage depends on the specific situation. And the needs of the tree.

Static anchoring is used in more urgent, high-risk situations where immediate stabilization is required.

Dynamic anchoring, on the other hand, is more often used for preventive measures and long-term support. Where the health and natural growth of the tree come first and thickness growth can gradually increase.

 

EAC Best Practices for Tree Cabling

The European Arboricultural Council (EAC) establishes best practices for “Tree Cabling” (the installation of cables and anchors in trees), to ensure effective and safe support. Some of these guidelines include:

Thorough inspection of the tree, analysis and determining measures

Before cables are laid, a detailed inspection must be carried out by our certified tree manager to ensure the health of the tree, the crown structure, and assess specific needs. As well as to determine the most suitable measures.

Often it is not enough to impose a single measure. But after finding the causes, you should select the most effective measures.

Right materials

Use only materials designed for crown anchoring, such as UV-resistant cables and corrosion-resistant hardware, to ensure durability and effectiveness.

Placement of a crown anchor

The placement and location of cable and hardware points of application, for both dynamic protection and static protection, should be carefully considered. So that you provide effective support without hindering the growth and health of the tree. And so that you do not organize additional overloading of branches or crown parts “yourself”.

Monitoring and maintenance of crown anchorages in trees

After installation, regular inspection and maintenance of the cable systems is necessary. To ensure that they are in good condition, remain in good condition and function effectively. An annual inspection is a minimum necessity.

Safety

Safety precautions must always come first. Especially when working in and around trees. To minimize risks for the environment, employees and visitors.

By following best practices, you can successfully apply crown anchors to extend the lifespan of trees and ensure the safety of the environment.

 

Pruning in combination with crown anchoring

When using tree cabling, or installing crown anchors, you will also often prune. To optimize the crown of the tree. And to ensure that the cables and anchors can do their work effectively, but especially to relieve parts of the weight and to ensure the right incidence of light.

This process requires careful analysis, planning and execution. To both improve the structural integrity of the tree and maintain the health and condition of the tree.

The pruning the tree in combination with placing crown anchors is an important step that serves several purposes:

Reduction of tax

Selective pruning of branches reduces the load on the crown anchorage. This helps prevent overloading of the anchors and cables, which reduces the chance of failure of the branch attachments and the system itself.

Improvement of the tree structure

Pruning helps shape the tree and correct structural weaknesses. Like competing leaders, abrasive branches, plaque shells, which can reduce or undermine the stability of the tree. You also improve the future by optimally organizing the light in the crown through pruning crown structure.

Removal of damaged parts

Damaged, dead or diseased branches can be removed to promote the overall safety of the tree. And possible spread of diseases or infestations to prevent.

 

Best Practices for Pruning When Installing Crown Anchors

When performing pruning and crown anchoring work, there are several best practices to keep in mind:

Thorough inspection

Before deciding and installing a crown anchor, regardless of type, carry out a thorough inspection of the tree. To determine which branches need to be pruned and where the application points of the crown anchors should be placed. To ensure optimal support and growth.

Pruning techniques

Use proper pruning techniques to minimize damage to the tree. This includes making clean cuts, in the right places. To promote the natural healing of the tree and prevent infections.

Timing of pruning

The ideal time for pruning may vary depending on the tree species. It is generally recommended to pruning during summer when the tree is at its maximum energy level. Sometimes, however, one has no choice but to intervene when an incident occurs with the tree.

Limit the size of the pruning

Do not prune more than necessary. Excessive pruning can cause stress and affect the health and condition of the tree. A general rule is to remove no more than 25% of a mature tree's leaf mass in one season. Don't prune every year either; allow the tree to return to its normal energy level.

Expert advice on pruning and crown anchors

Ask us expert advice, of ours tree manager, especially when it comes to problems with big trees go. Both for placing crown anchors and pruning. Our professional team can provide expert advice and ensure that the work is carried out in a safe and effective manner.

By following these guidelines, trees can be effectively supported and secured by installing crown anchors while maintaining their health and structure.

Combining crown anchorage with careful and strategic pruning leads to strong, stable trees. Which are more resistant to the natural elements and have a longer lifespan.