Editorial Dragon Trees, Tertiary Relicts in Current Reality Petr Mad ˇ era 1, *, Fabio Attorre 2 , Hana Habrová 1 and Kay Van Damme 1,3   Citation: Madˇ era, P.; Attorre, F.; Habrová, H.; Van Damme, K. Dragon Trees, Tertiary Relicts in Current Reality. Forests 2021, 12, 756. https://doi.org/10.3390/f12060756 Received: 2 June 2021 Accepted: 3 June 2021 Published: 8 June 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemˇ edˇ elská 3, 613 00 Brno, Czech Republic; hana.habrova@mendelu.cz (H.H.); kay.vandamme@gmail.com (K.V.D.) 2 Department of Environmental Biology, Sapienza-University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; fabio.attorre@uniroma1.it 3 Faculty of Sciences, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium * Correspondence: petrmad@mendelul.cz Few of the about 190 species currently described in the plant genus Dracaena [1] (Asparagaceae) reach the arborescent form. Arborescent dracaenas have been classified into the Dragon tree group [2]: Dracaena cinnabari Balf.f., D. tamaranae A. Marrero, R. S. Almeida et M. González-Martín, D. draco L. s.l., D. ombet Kotschy & Peyr. s.l. and D. serrulata Baker s.l., and D. ellenbeckiana Engl. from South Arabia, Macaronesia and North Africa. In addition, several species from Southeast Asia, such as D. jayniana Wilkin & Suksathan, D. cochinchinensis (Lour.) S. C. Chen, D. yuccifolia Ridl., D. cambodiana Pierre ex Gagnep. and D. kaweesakii Wilkin & Suksathan, can be included due to their tree growth habit [3–5]. Dragon trees are considered Tertiary relict species [6]. These trees have been part of one of the oldest woodland ecosystems in the world [7]. Most species are endemic with limited (often island) distributions [2,5,8,9]. The distribution of Dragon trees is highly fragmented, consisting of small populations with unbalanced age structures. Often young trees are missing because natural regeneration is reduced by the overgrazing of livestock [3,5,10–18]. Dragon trees can be found in areas characterized by a predominantly arid tropical climate with a monsoon seasonality bringing wet air in the form of clouds and fog [19, 20]. They are well adapted morphologically and physiologically to capture water in such conditions [21–23]. Several Dragon tree species are endangered (some are even extinct) according to the IUCN Red List, even though most of the species have not been assessed yet. Dragon trees are an important source of non-timber plant products for indigenous communities [24]. They produce a red resin, called dragon’s blood, which has been used for coloring and medical purposes since ancient times [25]. The dragon’s blood was an important trade product in Ancient Egypt and in the Greek and Roman empires [26,27]. Therefore, Dragon trees are among the plants that have played a key role in human history. They have, therefore, important natural and cultural values. Because of their global importance, we assembled a group of researchers and local practitioners engaged in the research and conservation of the vulnerable and often endan- gered arborescent Dracaena species of the world. To this goal, we organized the first World Conference on Dragon Trees, hosted by Mendel University in Brno (Czech Republic), on 5–8 September 2019. The conference hosted about 35 attendants from 12 different countries. The main objective of the event was to present the latest results of scientific research focused on species of the Dragon tree group and to determine the main gaps for future investigation as the basis for their conservation and management. An important output of the conference was the establishment of the first Dragon Tree Consortium, an informal open society that focuses on cooperation in Dragon tree research and conservation. The Special Issue includes nine studies covering a broad range of research topics related to Dragon trees. Celi ´ nski et al. [28] present the complete D. draco chloroplast genome, which provides new information and helps to elucidate phylogenetic relationships, particularly within the genus Dracaena. A new approach in taxonomy with a potential for Forests 2021, 12, 756. https://doi.org/10.3390/f12060756 https://www.mdpi.com/journal/forests