ANALYSIS OF AESTHETIC PREFERENCE OF TREE SHAPES USING VIRTUAL ENVIRONMENTS By Dr. Ayman Hassaan A. Mahmoud Lecturer, Department of Architecture, Faculty of Engineering, Cairo University, Giza 12211, Egypt- e-mail: alp97ahm@yahoo.co.uk ABSTRACT Traditional simulation techniques are limited to static and non-interactive experience of spaces. However, a review of recent literature suggests that virtual environments maintained realistic representations of real and proposed physical environments. It is argued that virtual environments’ simulation could provoke reliable impressions from users regarding their experience within simulated spaces. This paper reports findings of an investigation of the determinants of aesthetic preference of plants within simulated urban contexts. Plant materials’ attributes were based on previous research basically for three factors of plant form, plant size and planting location. An experimental design of a 3×3 Latin Square is employed to explore which of the three levels would be highly associated with preference responses towards the simulated environments in controlled conditions. Sixty participants reported their preference of virtual environments simulation of urban contexts representing every factor level. Analysis of results using Repeated Measures ANOVA and multiple regression revealed that sizes, and locations of trees provided greater contribution to the aesthetics preference of trees compared with tree forms. The findings would have direct implications for both practice and future research. Introduction This article reports findings on the specific issue of how well preference judgements can be predicted from plant attributes using virtual environments. There are four reasons why this work is needed. First, on an individual level, it would be useful for landscape designers to understand how effective different plant attributes are. If one wished to make a landscape context look better, and one had a choice between various forms or sizes of plant species, it would be helpful to know which change could provide greater benefit. The second reason why this work is needed is that the same choices must be made by users in the design development and evaluation process, but at the public level the decisions are no longer a matter of individual expression but also involve considerations of the proper roles of individuals and communities in forming the appearance of visual commons, Thus, more attention is needed in the formulation and execution of design review decisions than would be the case for individual expressions. The third reason why work on tree shapes is needed is that government practice in housing development in existing and new cities suggests that landscape designs may soon have to prove to be cost-effective. For example, if an urban design code required all trees to be places at same locations but different in forms, then the proponents of that decision would have the burden of demonstrating that the benefit of varying tree forms in front of buildings instead of planting side and backyards. The fourth reason motivating this study is that previous aesthetic preference studies used static and non-interactive simulation media as surrogates; however such media were criticised as being providing insufficient information to users. They lack validity and reliability as defined by Zube et al (1987) 1 . A review of recent literature on visual simulation techniques promoted virtual environments as reliable and efficient