Is leaning trees of Vatica pauciflora (Korth.) Blume related to their crown architecture?

Vatica pauciflora (Korth.) Blume (Dipterocarpaceae) or locally known as resak rawa is an important tree. It is categorized as vulnerable regarding the IUCN (International Union for Conservation of Nature) Red List of Threatened Species. We can find the resak rawa tree collection in the Bogor Botanic Gardens, which serves as a place for research and tourism. Due to the diversity in individual tree anatomy within species, understanding correlation among individual tree traits, particularly crown architecture and tree leaning, is of great interest. That will be important because the leaning trees and crown architecture will affect the risk level to the safety of visitors. We can also use the architecture of the tree crown to understand the factors that influence tree growth. This study aims to investigate the correlation between the leaning trees and the crown architecture of V. pauciflora. Eight heritage trees of the species in the Bogor Botanic Gardens at the age of 54–105 years old were purposely, sampled in this study. The variables observed were height, trunk and crown diameter, leaning tree, live crown ratio, and direction of the main branches. The results show that crown shapes will follow the leaning trees with a correlation of 0.97. The main branches will be longer in the direction of the leaning trees (y=0.9956x+11.312; R²=0.9431). Suggestions to the management of V. pauciflora are to provide information boards to visitors and pruning the crown in the direction of the leaning trees is needed. The findings could be used to formulate mitigation measures as to the risk and safety of visitors.

UCC Open Arboretum Project: Trees as a teaching and outreach tool for environmental and plant education

The University College Cork (UCC) Open Arboretum Project aims to re-imagine the original purpose of the University’s tree collection – as a teaching tool. The arboretum represents a unique on-campus learning space which has been under-utilised for teaching in recent times. The arboretum has the capacity to engage students, staff and visitors in a tangible way with important global issues (e.g. the climate emergency and biodiversity loss). It is also an opportunity to combat ‘plant blindness’, i.e. the ambivalence shown to plants in our environment compared to often charismatic animal species. Wandersee and Schussler (1999) coined the term “plant blindness” to describe the preference for animals rather than plants that they saw in their own biology students. Knapp (2019) has argued that, in fact, humans are less ‘plant blind’ and more ‘everything-but-vertebrates-blind’ with school curricula and television programming over-emphasising the role of vertebrates at the expense of other groups of organisms. Botanic gardens and arboreta have long been used for educational purposes. Sellman and Bogner (2012) have shown that learning about climate change in a botanic garden led to a significant shortterm and long-term knowledge gain for high-school students compared to students who learned in a classroom setting. There is also evidence that learning outside as part of a science curriculum results in higher levels of overall motivation in the students and a greater feeling of competency (Dettweiler et al., 2017). The trees in the UCC collection, like other urban trees also provide a range of benefits outside of the educational sphere. Large, mature trees, with well-developed crowns and large leaf surface area have the capacity to store more carbon than smaller trees. They provide shade as well as food and habitats for animal species as well providing ‘symbolic, religious and historic’ value in public common spaces. Such benefits have recently been summarised by Cavender and Donnolly (2019) and aligned with Sustainable Development Goal 11, Sustainable Cities and Communities by Turner-Skoff and Cavender (2019). A stakeholder survey has been conducted to evaluate how the tree collection is currently used and a tour of the most significant trees in the collection has been developed. The tour encourages participants to explore the benefits of plants through many lenses including recreation, medicine and commemoration. The open arboretum project brings learning beyond the classroom and acts as an entry point for learning in a variety of disciplines, not least plant science and environmental education generally.