Tree care

from Wikipedia, the free encyclopedia
Steel chains were attached to maintain the treetop

Tree care includes measures on the tree and tree environment to avoid undesirable developments as well as to ensure road safety and maintain the vitality of a tree.

construction

Basically, a rough distinction can be made between three different maintenance measures:

  • Tree care , gentle shape and care cuts, e.g. B. crown care , as well as improvements of the location, z. B. by fertilization or unsealing
  • Tree renovation , often more extensive measures on the tree in order to preserve it for people and the environment (tree conservation)
  • Tree surgery , special measures on sick or damaged trees (wound, rotten spots, root canal treatment), which were used until the late 1980s, was more damaging to trees than helpful. See CODIT

Arborist is a professional training from the professional fields of horticulture , forestry and agriculture .

Measures of tree care

Tree care from a platform from
Transplanting a plane tree

Normally, tree care is mainly carried out on trees on traffic routes or in settlement areas (increasing traffic safety , reducing shading ), on natural monuments . The main reasons for the necessity of tree care measures are the unnatural or spatially limited location and the demands that humans place on these trees with regard to health, appearance and safety. Common jobs of an arborist include:

  • Tree planting , as well as tree transplantation of larger specimens, an increasingly important field in garden design
  • Crown cut
  • Work in the root area , tree environment improvement, such as soil improvement,
  • Tree control and tree examination, also called tree diagnosis .

According to the definition, tree care can only be used if it involves professional measures that promote the tree in its vitality, traffic safety and development more than damage it.

Professional tree care: Tree care measures should

  • promote the further development of the tree
  • Treat diseases of the tree
  • Minimize negative, unavoidable influences (e.g. during construction work)
  • minimize the consequences of any damage or weaknesses
  • executed according to the development phase of the tree
  • be carried out in accordance with recognized methods
  • taking into account new advances and knowledge in this area

Improper tree care: Measures on the tree that do more harm than good to the tree and impair its growth or life expectancy are considered to be improper tree care. These include:

  • the cutting of trees
  • Measures that do not correspond to the respective development phase
    • Crown securing cut on an old tree in danger of breaking (if necessary, professional)
    • strong pruning of an adult tree without need (capping)
  • wrong cut
  • unnecessary strong branch cuts
  • severe damage to the trunk during pruning and pruning measures

Under certain circumstances, improper tree care due to tree damage can justify a claim for damages .

Crown cutting measures

Tree care measures on urban and park trees or on trees that were not planted for the sake of wood yield are mainly crown pruning measures .

Pruning measures are either constructive ( upbringing , crown care) by helping the tree to build a stable and healthy crown , or they are carried out as a precaution or for reasons of road safety as a safety measure (dead wood removal, clearance profile cut, crown care, crown shortening, shortening of crown parts, such as the removal of bad luck bars , as well as the crown protection ). The crown securing cut, as a very intensive intervention, serves to restore road safety if the tree cannot or should not be felled completely (e.g. for reasons of monument protection ). These cutting measures are described in regulations. It is u. a. also describes what can be described as a professional measure.

The fruit tree pruning only deals with the crown of the fruit trees and, as part of the job description of the fruit gardener / farmer, is not part of tree care due to significantly different requirements for the effects to be achieved.

Methods of tree care

Ideally, effective tree care does not only consist of a single, intensive intervention that has to do without further rework, but rather of constant care and correction of the plants through several small (more) interventions one after the other. Modern tree care tries to implement the correct measures based on scientific knowledge.

Methods in cutting

The cambium is more or less injured when cutting . The priority is a good overburdening of the cut in order not to make the so-called “partitioning”, a reaction in the living part of the wood to separate damage areas from healthy wood, more difficult against pests. To protect against mechanical wounds, a careful and planned work sequence is necessary, whereby the avoidance of the injury before the wound care is in the foreground. Correct use of the tools is part of the professional execution of tree care measures.

  • Cutting: Posture when cutting, sharpness and the type of scissors used are decisive for a clean cut. With anvil shears , a cutting edge hits a flat surface, squeezes the branch on both sides and therefore creates an unnecessary enlargement of the cut wound on the remaining branch. With secateurs of the type of secateurs , the cutting blade moves past the counterblade, as with conventional paper scissors. This means that only one side of the branch is squeezed, which is done by turning the scissors appropriately on the removed part.
  • Sawing : With set saws , the rough cut surface must be recut . (This trimming is done parallel to the cut surface, a cut at a 45 ° bevel proves to be disadvantageous.) For this reason, Japanese saws were sometimes used , which work “on pull” and can also be used on the telescopic rod (5–8 m, even more). In recent years, special tree saws have become increasingly popular, mostly from the Japanese manufacturers Silky and ARS - both as telescopic and hand saws.
  • Protection against spreading infection: To protect against spreading pathogens, the tool should be disinfected (water-alcohol solution, if necessary more special agents).

In addition to the quality of the tool, the execution of the cut is actually the critical aspect. If the cut is too far away from the supporting branch or trunk, a stump is created which, after it has died, offers another entry wound for tree fungi ( xylobionts ) that are harmful to the tree . The stump is too far away from the sap flow to be closed off by overburden against pests. If the cut is made too close to the trunk or main branch, an unnecessarily large wound occurs, which takes a long time to heal. Under certain conditions, stubs are deliberately cut ( rubber flow with pome fruit). Furthermore, in order to prevent splicing or peeling of the bark when the branch is thrown off, work is carried out in steps so that the cut to be healed is not made under load.

Wound closure

The discussion about the closure of cuts with commercially available means is sometimes controversial. On the one hand, the tree independently forms protective wood; on the other hand, the applied wound closure may prevent wound edge necrosis . It is still possible to treat fresh and existing collision damage and similar wounds with wound closure. In the case of fresh wounds, it is often sufficient to reattach the bark; you can either tie it down or work with small nails. This can overwhelm and seal off the plant relatively easily . The foreign bodies trapped in this way no longer pose a health risk to the plant. In contrast to forgotten and non-rotting cords, which then even cause greater damage in the course of growth. In order to avoid wound edge necrosis when removing larger branches, which should be avoided as far as possible, it is sometimes recommended to apply wound closure (e.g. tree tar ) to the cut edges to limit damage. Overwelling and sealing off wounds is only possible during the vegetation period, so it makes sense to postpone cutting work during this period. In the case of some tree species ( e.g. poplar and willow ), the ability to react to injuries is generally poor, here early formation (only small wounds) or the general avoidance of pruning measures are recommended.

Methods that were still popular until the 1970s, such as filling cracks or wounds with concrete , as practiced by Michael Maurer among others , are now viewed extremely critically after bad experiences. Often, sealing it airtight was the first to encourage the decomposition to progress.

Site protection

Formwork on a construction site in Itzehoe

Protection against location-related mechanical damage:

  • Impact and grazing damage : One of the most common causes of damage can be seen in automobiles and construction work. The most frequent occurrence here is not the collision, but rather the careless peeling of the bark. In road traffic, this is usually only possible through structural measures. The same applies to construction work; cladding is also possible here.
  • Driving damage : The problem in the traffic area is the damage to the roots caused by driving over the entire edge of the eaves , i.e. the area that is shaded by the outermost branches. As a result, the necessary water and air can hardly reach the roots. There are already individual methods of restoring the permeability of compacted soil (e.g. aeration using compressed air using lances). Avoidance, e.g. B. by corresponding relief of the entire root disc with continued traffic, has priority here.

Treating damage from parasites and diseases

Parasites can often only penetrate the tree through the bark damage mentioned above or through some other weakening of the tree (climate, pollutants, etc.).

Penetrating fungi are at least temporarily prevented from spreading by the tree through the formation of protective wood . The resulting hollow tree trunks are still stable for a very long time, approx. 70% of the cross-sectional area can be lost without losing the break resistance. If the losses are already higher, a strong setback of the crown should reduce the pressure of the wind. Before that, however, an expert opinion should discuss the exact situation of the tree. However, if the principle of the "closed tube" of a hollow trunk is weakened by further damage, the load-bearing capacity of the trunk falls further.

The infested areas in fruit tree cancer should be cut free of infected material. It has to be cut into the healthy tissue to prevent further infection. The tools must be disinfected.

Boring insects can hardly be combated inside the tree; those species that only attack open wood are prevented from attacking by treating the wounds. For those insects that also attack healthy trees, the exposure to attractant traps can be sensibly reduced.

The further treatment corresponds to the procedure as for mechanical damage.

Arborist as a job description

The field of tree care and maintenance is carried out by the arborist , a specialist in the profession of agricultural specialist (FAW - Germany) or agricultural technician or forest warden (Austria, Switzerland). The pan-European qualifications European Tree Worker (ETW) and European Tree Technican have been established for several years . While the former is a further qualification below the skilled worker level for arborists, the ETT was located at the same level as the German FAW.

In Germany there are now certifications from institutions ( EAC , ISA , Fachagrarwirt Baumpflege und Baumanierung ), which are supposed to guarantee a quality standard. The HAWK University of Applied Sciences and Arts - Hildesheim / Holzminden / Göttingen University of Applied Sciences also offers a bachelor's degree in arboriculture .

In addition to the basics of actual tree care, the training also includes tree biology and climbing techniques ( rope-assisted tree climbing technique for short).

In Switzerland, there has been training to become a tree care specialist with a federal certificate since 1991. Depending on your previous education, it lasts between two and four years.

literature

General
  • Alex L. Shigo : Modern Tree Care. Basics of tree biology (original title: Modern Arboriculture ). Translator: Rolf Kehr, Heinz Butin . Thalacker, Braunschweig 1994, ISBN 3-87815-051-2 .
  • Dirk Dujesiefken, Walter Liese : The CODIT PRINCIPLE - Learning from trees for professional tree care. Haymarket Media, Braunschweig, ISBN 978-3-87815-227-9
  • Alex L. Shigo: Tree pruning . Series TASPO knowledge . Original title: Tree Pruning. Translator: Aloys Bernatzky . Thalacker, Braunschweig 1991, ISBN 3-87815-033-4 .
  • Dirk Dujesiefken (Ed.): Wound treatment on trees. Thalacker, Braunschweig 1995, ISBN 3-87815-052-0 .
  • Johannes von Malek, Werner Molitor, Karl Peßler: The arborist. Ulmer (Eugen), 1999, ISBN 3-8001-5070-0 .
  • Peter Klug: Tree care practice - cutting crowns on trees . Arbus Verlag, Steinen 2006, ISBN 3-934947-11-5 .
  • European Arboricultural Council: European Treeworker . Patzer Verlag, Berlin / Hanover 2011, ISBN 978-3-87617-121-0 .
  • Dietrich Kusche, Marek Siewniak: Tree care today. Patzer Verlag, Berlin / Hanover 2009, ISBN 978-3-87617-115-9 .
  • Lothar Wessolly, Martin Erb: Manual of tree statics and tree control. Patzer Verlag, Berlin / Hanover 1998, ISBN 3-87617-093-1 .
  • Michael Schlag, Hermann Reinartz: Fungi on trees . Patzer Verlag, Berlin / Hannover 2005, ISBN 3-87617-111-3 .
Norms and standards
media

Web links

Commons : Tree maintenance  - collection of images, videos and audio files

Individual evidence

  1. Germany: ( ZTV Tree Care ; ZTV = Additional Technical Contractual Conditions and Guidelines for Tree Care)
  2. The use of wound closure agents when pruning trees and fruit trees . August 21st, 2013.
  3. http://www.bio-gaertner.de/Obstbaeume/Obstbaeume-Wundschluss
  4. http://www.baumpfleger.at/wundschluss.html
  5. https://www.daserste.de/information/wissen-kultur/w-wie-wissen/sendung/2011/der-baumdoktor-kom-mit-der-spritze-100.html
  6. Study course in arboriculture at the University of Applied Sciences in Göttingen