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Arboricultural Practices

Authors:
  • Institut für Baumpflege / Institute of Arboriculture
  • Etablissement public CNPF
  • Institut für Baumpflege Hamburg

Abstract

Arboriculture (from the Latin arbor = tree, cultura = tending or caring) is tree cultivation based on tree biology. The term arboriculture is often loosely used and includes the care of other woody plants such as vines (in the United States), wall shrubs (in England), and climbing shrubs (in Australia). This relatively young discipline generally focuses on single trees or small groups of trees, usually in urban areas. Arboriculture is an essential and integral part of urban forestry and is sometimes treated as a special type of horticulture. The goals of arboriculture are to establish and maintain healthy, aesthetic, and safe trees. These goals are met through the selection of suitable tree species for harsh urban conditions, proper planting, watering, fertilization, mulching, protection (stakes, supports), and formative pruning of new plantings as well as through proper training, regular pruning, vitality and safety inspections of mature trees. This chapter deals with the assessment of trees and the most commonly applied tree care practices: pruning, crown stabilization and wound treatment. Targeted tree care should rely on knowledge of their growth and response to adverse urban conditions inducing the decrease of tree vitality and simultaneous increase of hazard problems. Among several methods for assessment of tree vitality, visual methods will deserve most attention due to their practical value. Identification of dangerous trees and decision for solution of the problem is a highly responsible procedure, which demands expertise in tree biology and diagnostic methods. Hence, the process of walling-off of infected and decayed wood tissue and a range of methods used for assessment of hazard trees will be considered in this chapter.
... Cupressus sempervirens L. and Chamaecyparis lawsoniana Murray trees in plots A and D showed lower values of crown base height and limited crown width, due to their characteristic canopy shape. The broadleaved trees in plot F, despite limited height, present a well-developed canopy due to both the absence of competition for light (Bechtold 2003) and the effects of pruning (Drenou 2000;Dujesiefken et al. 2005), assuming a common canopy shape for trees in the city. The comparison between the DBH and tree height measurements of the smartphone with those carried out with the tree caliper and the electronic ipsometer showed a strong correlation (r-values of 0.98 and 0.95, respectively) (Figure 3). ...
... Tilia cordata Mill. and Aesculus hippocastanum L. show higher values than other tree species, not only for foliage properties but also for the effect of management that tends to compress the crown by increasing leaf density (Dujesiefken et al. 2005). The shading factor of Cedrus libani A. Rich. is similar to Magnolia grandiflora L. but greater than Pinus pinea L. In fact, the cedar crown architecture is not comparable to other conifers with greater leaf density, such as firs or cypresses, demanding a specific class. ...
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... Sharp changes in demography, economic and agricultural activities, stock raising and forestry practices, linked to the industrialisation and rural depopulation during the last two centuries across most part of Europe, has caused the progressive abandonment or reduction of traditional multipurpose land uses, pollarding practices included (Read 1996;Moe and Botnen 2000;Leppik et al. 2011;Castro et al. 2012;Sjölund and Jump 2013). The practice of pruning trees at height is both costly and risky (Dujesiefken et al. 2005), and leaves and branches from trees are no longer a critical resource for local subsistence farming economies (Nordén et al. 2018). Consequently, pollarding practice has been progressively reduced or abandoned, and most former pollard woodlands have evolved into closed forests, or were transformed into forest plantations or agricultural lands, with this process intensifying during the latter half of the twentieth century (Pankhurst 2013). ...
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... In the field, evaluating the physiological state of trees is challenging, since most methods are simply based on foliage discolouration and loss and do not take the resilience capacity of trees into account (Dujesiefken et al., 2005;Lambert et al., 2013). The ARCHI method (Lebourgeois et al., 2015;Drénou et al., 2015) is able to assess resilience capacity. ...
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... According to the existing definition: "hazard is a disposition of a thing, condition, or situation to produce injury" (Health and Safety Executive, 1995), in a more specific way a tree is considered to be hazardous, if it is structurally unsound and there is a possible target, like vehicles or people. An unsound tree in an area with no target is not hazardous (Dujesiefken et al.., 2005). Although all trees have a potential to fail and become hazardous in particular conditions, senescent trees are most prone to acquire these characteristics. ...
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... However, the high environmental value of city trees seems to be contradictory to the often stressful conditions under which urban trees are thriving. Although tree establishment and management practices have improved in many European cities (Pauleit et al. 2002;Dujesiefken et al. 2005;Sieghardt et al. 2005), the specific climate and site conditions at sealed urban sites limit healthy tree life to a major extent . Soil sealing determines the degree of infiltration, the rate of surface run-off, and further restrict water supply for plants (Blume 2000;Bhaduri et al. 2001;Conway 2007). ...
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