**Woody Plants in Landscape Planning and Landscape Design**

Viera Paganová and Zuzana Jureková *Slovak University of Agriculture in Nitra Slovak Republic* 

#### **1. Introduction**

198 Landscape Planning

Lankford, S.V., Howard, D.R. (1994). Developing A Tourism Impacts Attitude Scale. *Annals* 

Lee, T.J., Li, J., Kim, H. (2007). Community residents' perceptions and attitudes towards

Mason, P., Cheyne, J. (2000). Residents' Attitudes To Proposed Tourism Development.

Oztürk Kurtaslan, B., Demirel, Ö. (2011). Pollution Caused By Peoples' Use For Socio-

Pereira, R., Soares, A.M.V.M., Ribeiro, R., Gonçalves, F. (2005). Public Attitudes Towards

Puczkó, L., Rátz, T. (2000). Tourist and Resident Perceptions Of The Physical Impacts Of

Sertkaya, Ş. (2001). A Study On The Determination Of Tourism and Recreation Potential Of

Issues, pp. 239–249 (Washington D.C.: George Washington University). Soutar, G.N., McLeod, P.B. (1993). Residents' Perceptions On The Impact Of The America's

Tourism. Final Report. [accesses 2012 January]. Available from:

*Journal of Sustainable Development & World Ecology,* 11(4), 410-422.

Phenomenon; [accesses 2012 January]. Available from:

United Nations Environment Programme, (2009). A Three-Year Journey For Sustainable

 http://www.unep.fr/scp/tourism/activities/taskforce/pdf/TF%20REPORT\_FINAL.pdf United Nations World Tourism Organization, (2012). Tourism – An Economic and Social

Welford, R., Ytterhus, B. (2004). Sustainable Development and Tourism Destination

Yaslioglu, E., Akaya Aslan, S.T., Kirmikil, M., Gundogdu, K.S., Arici, I., Arici, C.F. (2007).

Yatgn, H. (1996). Floristic Compositions Of Amasra. Ms.C thesis. Zonguldak Karaelmas

Yazgan, M.E., Kapuci, C., Cengiz, B. (2005). Sustainability Of Tourism and Ecotourism in

Yazgan, M.E., Kapuci, C. (2007). İznik City with Its Historical Landscape Properties.

Management: A Case Study Of The Lillehammer region, Norway. *International* 

Environmental Protection-Based Village Development: The Case Of Eskikaraagac.

University, Graduate School of Natural and Applied Sciences, Department of

Coastal City Amasra. pp. 259-266. Proceedings of the Seventh International Conference on the Mediterranean Coastal Environment, MEDCOAST 05, E. Özhan

Environment: Survival and Sustainability- ESS'07. February 19-24, 2007. Vol. 3, pp.

heritage tourism in a historic city. *Tourism and Hospitality Planning & Development,*

Economic Purposes (Agricultural, Recreation and Tourism) In The Gölcük Plain Settlement at Bozdağ Plateau (Ödemiş-İzmir/Turkey): A Case Study. *Environmental* 

The Restoration and Management Of Lake Vela (Central Portugal). *Fresenius* 

Tourism at Lake Balaton, Hungary: Issues For Sustainable Tourism Management.

The Bartn Coastal Zone. Ph.D. thesis. Ankara University, Graduate School of Natural and Applied Sciences, Department of Landscape Architecture, Ankara (in Turkish). Sethna, R.J. (1980). Social Impact Of Tourism In Selected Caribbean Countries, In D. E.

Hawkins, E. L. Shafer, and J. M. Rovelstad (eds.) Tourism Planning and Development

*of Tourism Research,* 21(1), 121-139.

*Annals of Tourism Research,* 27(2), 391–411.

*Monitoring and Assessesment,* 175, 419–430.

*Journal of Sustainable Tourism,* 8(6), 458-478. Sakaoğlu, N. (1999). Çeşm-i Cihan / Amasra. Bartn (in Turkish).

Cup. *Annals of Tourism Research,* 20(3), 571–582.

*Fresenius Environmental Bulletin,* 16(8), 940-947.

Landscape Architecture, Bartn (in Turkish).

(Editor), 25-29 October 2005, Kuşadas, Turkey.

955-962, Cyprus.

http://unwto.org/en/content/why-tourism

*Environmental Bulletin,* 14(4), 273-281.

4(2), 91-109.

Vegetation is considered to be a significant element of the landscape. The greenery elements design landscape scenery and have productive and eco-stabilizing functions in the landscape area. Woody plants have a specific position within the greenery elements. They have bigger dimensions in comparison to the other plants, their organs usually have large surfaces and their biomass fills large parts of the overhead space and the soil. Trees and shrubs have great influence on the environment and living conditions of the other organisms. Short-term changes in ecosystems do not significantly impact their lifecycle and survival. Woody plants are long-lived organisms with different adaptability to changes of environmental conditions. The knowledge of the morphological characteristics, as well as biological and ecological qualities of woody plants is very important for their efficient utilization (Paganova, 2006; Paganova et al., 2010; Sjöman, 2012; Valladares et al., 2007).

In urban conditions woody plants have several environmental, economic and social benefits. Trees reduce heat, wind speed and provide shading, increasing the energy efficiency of buildings (Sand, 1994; Simpson, 1998; McPherson & Simpson, 2003). Urban greenery increases the sociological value of the environment, improving the aesthetic and hygienic properties of the particular place. It also increases positive feelings and moods, enjoyment of everyday life and stronger feelings of connection between people and the environment (Dwyer et al., 1992, 2003; Westphal 2003).

However, environmental conditions in urban areas are significantly different to natural habitats. Plants in urban areas are exposed to many negative factors like: water deficit, soil compaction, pollutants, artificial lighting, overheating of the root zone and mechanical injuries. According to Nilsson et al. (2000), street trees are exposed to multiple stresses and their average lifespan is short. Park trees are exposed to moderate stress and compared to street trees their lifespan is relatively high. In urban woodlands the level of stress depends more on climate, soil conditions, recreational patterns and biotic damages rather than on anthropogenic causes (Sæbo et al., 2003).

Proper woody plant selection for specific conditions and establishment of the effective vegetation elements increases the functionality and stability of the landscape area (Paganova, 2004; Paganova, 2006). Like all living organisms, woody plants change in time

Woody Plants in Landscape Planning and Landscape Design 201

Fig. 1. Two individuals of *Sorbus domestica* on open stand with significantly different phenotypical traits of the crown architecture (shape, density and angle of branching)

physiology of urban trees has until now been rather overlooked (Sæbo et al., 2005).

plant water regime parameters, structural leaf and root adaptations etc.

suitable for extreme conditions of urban and landscape environment.

**4. Selection of woody plants for landscape and urban greenery in Slovakia**

From the scientific point of view mainly the ecological criteria of selection, the adaptability of trees to local conditions and the functional aspects of trees in the urban environment are studied and evaluated. The ecophysiological characteristics of trees are effective tools for selection. The stress responses of woody plants are considered to be key to the selection criteria and to markers that can be used in tree improvement programmes for specific urban conditions. Although much information can be found on environmental tree physiology (Kozlowski et al., 1991), the stress

According to Ware (1994), extreme conditions of the original stand can be a good starting point for finding plants adapted to stressful urban environments. Drought is a significant factor influencing the existence and lifecycle of woody plants. However, taxa with similar ecological backgrounds (light-demanding and tolerant to water deficiency) probably use different strategies to overcome water stress impact (Paganova et al., 2010). Explanation of these mechanisms needs more experimental work and larger data files, as well as addition of information on other characteristics of drought impact such as changes of the assimilatory pigments, accumulation of osmoprotectants, water use efficiency (WUE), dynamics of the

Service tree (*Sorbus domestica* L.) and wild pear (*Pyrus pyraster* L. Burgsd.) are lightdemanding species tolerant to water deficiency during the growing season (Brutsch & Rotach, 1993; Rittershoffer, 1998; Wilhelm, 1998; Paganová, 2003a, 2008; Paganová & Jureková, 2012). According to the ecology background, these woody plants are potentially

(Maceková, 2011).

and space, and knowledge of the nature and dynamics of these changes is essential for their successful utilization in landscape planning.

#### **2. Principles of woody plant selection for landscape planning**

The selection of proper plants for specific stand conditions is a very important task that affects success in the landscape planning and landscape design.

In Europe recent studies (Pauleit et al., 2002; Sæbo et al., 2003; Sæbo et al., 2005) documented poor diversity of tree genera and species planted in urban areas. A few genera of woody plants (*Acer*, *Aesculus*, *Platanus* and *Tilia*) are used as street trees. The number of species planted in parks, gardens and residential zones is high, however, an increase in the number of species used for urban forestry is essential. Higher diversity of species used in landscape planning and design would increase ornamental value and longevity of the plantings, and decrease costs of establishment and regular maintenance.

Spellenberg & Given (2008) reviewed the general criteria for selection of trees for urban environments. According to their worldwide knowledge, the most important criteria for selecting trees for urban environments are rather pragmatic: suitability of the taxa for local conditions, low maintenance and avoidance of structural problems. Criteria that contribute to landscape design appear to be next in importance. The authors documented a predominance of artificial mixes of woody plant species in urban areas, which possibly increases the detrimental effects of urbanization on nature and habitats.

However, there are many activities which aim at preservation and utilization of indigenous species in landscape planning and landscape design, including urban areas (Breuste, 2004; Dunnet & Hitchmough, 2004; Florgård, 2004). The new planning and design concept allows using parts of nature with specific beauty and amenity for urban spaces as well as using native species and their communities for urban plantings.

Utilization of indigenous species should support increased biodiversity in urban areas with ecologically better balanced plant communities.

#### **3. Scientific tools of woody plant selection for landscape planning**

Use of non-traditional woody plant species (species that are not commonly used) in landscape planning and landscape design is quite difficult. In the opinion of many professionals some stereotypes in dealing with urban trees remain with regard to the suitable and unsuitable species for urban environments. Such species are rare on plant markets because their propagation protocols have not yet been elaborated upon and the qualified sources of reproductive material are missing. There are also different opinions about the possibilities of establishment and utilization of tree species on particular stands.

The lack of information and data about growth rate, growth characteristics and maintenance management of non-traditional tree species is another reason why they are not included in landscape and urban plantings. The selection of woody plants established just on their ecological background is not appropriate for specific conditions with cumulative impact of various stresses. Also assessment of growth and physiological parameters directly on trees growing in the field or urban conditions does not give relevant results, because they are influenced by many barely quantified factors.

and space, and knowledge of the nature and dynamics of these changes is essential for their

The selection of proper plants for specific stand conditions is a very important task that

In Europe recent studies (Pauleit et al., 2002; Sæbo et al., 2003; Sæbo et al., 2005) documented poor diversity of tree genera and species planted in urban areas. A few genera of woody plants (*Acer*, *Aesculus*, *Platanus* and *Tilia*) are used as street trees. The number of species planted in parks, gardens and residential zones is high, however, an increase in the number of species used for urban forestry is essential. Higher diversity of species used in landscape planning and design would increase ornamental value and longevity of the plantings, and

Spellenberg & Given (2008) reviewed the general criteria for selection of trees for urban environments. According to their worldwide knowledge, the most important criteria for selecting trees for urban environments are rather pragmatic: suitability of the taxa for local conditions, low maintenance and avoidance of structural problems. Criteria that contribute to landscape design appear to be next in importance. The authors documented a predominance of artificial mixes of woody plant species in urban areas, which possibly

However, there are many activities which aim at preservation and utilization of indigenous species in landscape planning and landscape design, including urban areas (Breuste, 2004; Dunnet & Hitchmough, 2004; Florgård, 2004). The new planning and design concept allows using parts of nature with specific beauty and amenity for urban spaces as well as using

Utilization of indigenous species should support increased biodiversity in urban areas with

Use of non-traditional woody plant species (species that are not commonly used) in landscape planning and landscape design is quite difficult. In the opinion of many professionals some stereotypes in dealing with urban trees remain with regard to the suitable and unsuitable species for urban environments. Such species are rare on plant markets because their propagation protocols have not yet been elaborated upon and the qualified sources of reproductive material are missing. There are also different opinions about the possibilities of establishment and utilization of tree species on particular stands. The lack of information and data about growth rate, growth characteristics and maintenance management of non-traditional tree species is another reason why they are not included in landscape and urban plantings. The selection of woody plants established just on their ecological background is not appropriate for specific conditions with cumulative impact of various stresses. Also assessment of growth and physiological parameters directly on trees growing in the field or urban conditions does not give relevant results, because they are

successful utilization in landscape planning.

**2. Principles of woody plant selection for landscape planning**

affects success in the landscape planning and landscape design.

decrease costs of establishment and regular maintenance.

native species and their communities for urban plantings.

ecologically better balanced plant communities.

influenced by many barely quantified factors.

increases the detrimental effects of urbanization on nature and habitats.

**3. Scientific tools of woody plant selection for landscape planning**

Fig. 1. Two individuals of *Sorbus domestica* on open stand with significantly different phenotypical traits of the crown architecture (shape, density and angle of branching) (Maceková, 2011).

From the scientific point of view mainly the ecological criteria of selection, the adaptability of trees to local conditions and the functional aspects of trees in the urban environment are studied and evaluated. The ecophysiological characteristics of trees are effective tools for selection. The stress responses of woody plants are considered to be key to the selection criteria and to markers that can be used in tree improvement programmes for specific urban conditions. Although much information can be found on environmental tree physiology (Kozlowski et al., 1991), the stress physiology of urban trees has until now been rather overlooked (Sæbo et al., 2005).

According to Ware (1994), extreme conditions of the original stand can be a good starting point for finding plants adapted to stressful urban environments. Drought is a significant factor influencing the existence and lifecycle of woody plants. However, taxa with similar ecological backgrounds (light-demanding and tolerant to water deficiency) probably use different strategies to overcome water stress impact (Paganova et al., 2010). Explanation of these mechanisms needs more experimental work and larger data files, as well as addition of information on other characteristics of drought impact such as changes of the assimilatory pigments, accumulation of osmoprotectants, water use efficiency (WUE), dynamics of the plant water regime parameters, structural leaf and root adaptations etc.

#### **4. Selection of woody plants for landscape and urban greenery in Slovakia**

Service tree (*Sorbus domestica* L.) and wild pear (*Pyrus pyraster* L. Burgsd.) are lightdemanding species tolerant to water deficiency during the growing season (Brutsch & Rotach, 1993; Rittershoffer, 1998; Wilhelm, 1998; Paganová, 2003a, 2008; Paganová & Jureková, 2012). According to the ecology background, these woody plants are potentially suitable for extreme conditions of urban and landscape environment.

Woody Plants in Landscape Planning and Landscape Design 203

These woody plants are part of the original flora in Slovakia. For both taxa large seasonal and phenotypic variability has been documented (Pagan & Paganová, 2000; Paganová, 2003b) that represent a good basis for targeted selection of genotypes with the qualities required for landscape planning and design. Species with high phenotypic plasticity it is assumed survive better on stands with changing environmental conditions. They have higher adaptability to changes by modifications of their functions and structures which increases the probability of their survival and reproduction. However, environmental conditions on stands affected by anthropogenic activities change too fast for manifestation of the evolutionary mechanisms of the plant adaptation (Sultan, 2004), so non-hereditary changes of plants – acclimations – take place. This is why detailed evaluation of the adaptability and phenotypic plasticity of non-traditional or rare woody plants is an essential

**4.1 Assessment of the potential sources of reproductive material of woody plants**

Within programme selection focused on woody plant species for landscape and urban greenery the following steps are essential: qualitative assessment of the potential gene pool of the particular taxon, identification of the appropriate sources of reproductive material in the natural conditions and inclusion of the selected components of the gene pool in the selection and breeding programme of woody plants for targeted utilization in landscape

In Slovakia the sources of reproductive material have not yet been identified for *Sorbus domestica* and *Pyrus pyraster*. Therefore, we devote a targeted assessment of phenotypic traits of individuals (growing on the original stands in the landscape), that can be used as a qualified source of the reproductive material (Fig. 2 and 3). The identification of the phenotypes suitable for wider plant production is a significant assumption for systematic

So far, attention has been paid to a reliable method of phenotypic classification of *Sorbus domestica* on original stands. Options and tools of their interpretation for selection of the sources of reproductive material were also analysed within a field study in the cadastre of the village of Žemberovce (Paganová & Maceková 2011). The scale of quantitative and qualitative parameters was elaborated and confirmed in 2011. For individual trees several parameters were determined which represent tree habit, tree growth and volume

Architectural traits, such as patterns of branching or clonal spread and production of terminal versus axial inflorescences, may also vary plastically in certain taxa. These traits provide very important insight into the structural and ultrastructural levels at which phenotypic adjustment takes place in the plant body (WU Stettler 1998). Therefore, we also apply them within the selection of indigenous woody plant species and their phenotypes

Crown traits, such as branch diameter, branch angle and branch frequency, are also important determinants for the quality of woody plants and timber products (Bowyer et al., 2002). These characteristics also affect the utilization of woody plants in urban areas with limited space for tree growth. According to the literature, variability of the growth habit and

tool when assessing their wider utilization in the urban landscape.

vegetation units, as well as in urban areas.

production (Fig. 4) (Tab. 1).

suitable for urban landscapes and greenery.

planting and use of the mentioned woody plant species.

Fig. 2. Service tree (*Sorbus domestica* L.) with a straight stem, regular crown and thin branching in the late autumn aspect in a vineyard. A "Plus tree" with positive phenotypic characteristics (Maceková, 2011).

Fig. 3. A young wild pear (*Pyrus pyraster* L. Burgsd.) with conical crown and thin branches, growing on abandoned grazing land (Šenšel, 2009).

Fig. 2. Service tree (*Sorbus domestica* L.) with a straight stem, regular crown and thin branching in the late autumn aspect in a vineyard. A "Plus tree" with positive phenotypic characteristics

Fig. 3. A young wild pear (*Pyrus pyraster* L. Burgsd.) with conical crown and thin branches,

growing on abandoned grazing land (Šenšel, 2009).

(Maceková, 2011).

These woody plants are part of the original flora in Slovakia. For both taxa large seasonal and phenotypic variability has been documented (Pagan & Paganová, 2000; Paganová, 2003b) that represent a good basis for targeted selection of genotypes with the qualities required for landscape planning and design. Species with high phenotypic plasticity it is assumed survive better on stands with changing environmental conditions. They have higher adaptability to changes by modifications of their functions and structures which increases the probability of their survival and reproduction. However, environmental conditions on stands affected by anthropogenic activities change too fast for manifestation of the evolutionary mechanisms of the plant adaptation (Sultan, 2004), so non-hereditary changes of plants – acclimations – take place. This is why detailed evaluation of the adaptability and phenotypic plasticity of non-traditional or rare woody plants is an essential tool when assessing their wider utilization in the urban landscape.
