From dangerous branches to urban banyan: Facilitating aerial root growth of Ficus rubiginosa

Autoři: Angela T. Moles aff001;  Ashika Jagdish aff001;  Yameng Wu aff001;  Suzanna Gooley aff001;  Rhiannon L. Dalrymple aff001;  Phoebe Feng aff001;  Jennifer Auld aff001;  Georgia Badgery aff001;  Matilda Balding aff001;  Andrew Bell aff001;  Nora Campbell aff001;  Mark Clark aff002;  Michelle Clark aff001;  Kyle M. Crawford aff001;  Oliver de Lorenzo aff001;  Amelia Fletcher aff001;  Zoe Ford aff001;  Haley Fort aff001;  Simon B. Z. Gorta aff001;  Alexander Hagan aff001;  Frank A. Hemmings aff001;  Gabriella S. Hoban aff001;  Thomasine Hulme aff001;  Kit King aff001;  Anish Kumar aff001;  Angelique Kyriazis aff001;  Beatrice Alexandra Laitly aff001;  Joshua Markovski aff001;  Len Martin aff001;  Geoffrey McDonnell aff001;  Cindy Pan aff001;  Ruby Paroissien aff001;  Polly Reeves-Perrin aff001;  Michi Sano aff001;  Sebastian M. Schwarz aff001;  Alena Sipka aff001;  Michael Sullings aff003;  Jing Wei Yeong aff001;  William K. Cornwell aff001
Působiště autorů: School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, Australia aff001;  Estate Management, UNSW Sydney, Sydney, NSW, Australia aff002;  Sydney Arbor Trees, Botany, NSW, Australia aff003
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
prolekare.web.journal.doi_sk: 10.1371/journal.pone.0226845


Large urban trees have many benefits. However, falling branches pose a serious hazard to both people and infrastructure. In several tree species, aerial roots grow down from branches to the ground. These roots are capable of thickening to support the branches, lessening the risk of tree failure. Unfortunately, in urban environments most aerial roots die before reaching the ground. Here, we report a new method for encouraging aerial roots to reach the ground, developed by the second-year botany class at UNSW Sydney. Our class tested three experimental treatments on aerial roots of Ficus rubiginosa Desf. ex Vent. (Port Jackson Fig)—PVC pipes filled with sphagnum moss, PVC pipes filled with potting mix, and PVC pipes filled with sphagnum moss and topped with funnels to catch extra rainwater. All three treatments significantly improved aerial root growth, with 26 of the 30 (87%) treatment roots reaching the ground after one year compared to 0 of the 10 control roots. Our method was successful for roots up to 3 m above the ground, suggesting the potential growth rate of aerial roots is substantial when conditions are favourable. Our novel approach is an attractive and cost-effective alternative to slings and other artificial supports. This project is an example of using undergraduate practical classes to teach science while simultaneously addressing important real-world problems.

Klíčová slova:

Mosses – Plant science – Polyvinyl chloride – Root growth – Trees – Undergraduates – Urban environments – Ficus


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2019 Číslo 12