Zelkova abelicea on Crete

Zelkova abelicea (Lam.) Boiss. is the only endemic tree of the Mediterranean island of Crete. Less than 45 populations of Z. abelicea are known, mainly in Levka Ori (ca. 30) and in the Dikti Mountains (ca. 10). Only one population occurs in the Psiloritis Mountains, one on Mount Kedros and one small population in the Thripti Mountains. Recent studies show however, that all populations incur threats by overgrazing and browsing (goats and sheep), as well as from soil erosion, drought and fires. 

Leading institutions: Mediterranean Agronomic Institute of Chania (Christini Fournaraki & Panagiota Gotsiou), Forest Directorates of Crete, University of Fribourg (Laurence Fazan)

Ex situ plantation of Zelkova abelicea with primary school of Skine-Fourne

As part of the Zelkova abelicea conservation project, an ex situ plantation was established in the Levka Ori with the involvement of the Municipality of Platanias, the Forest Directorate of Chania (FDC), the Mediterranean Agronomic Institute of Chania (MAICh) and the local Primary school of Skine-Fourne. The purpose of this ex situ plantation is manifold. The primary goal is to conserve the genetic diversity of the local Z. abelicea stands outside the natural populations so as to have a supply of trees in case a dramatic event happens and destroys the natural populations. Another important goal is to give more visibility to this species and help promote environmental education and public awareness. In the long term, the plantation will also provide wood of certified origin for making katsounes, the traditional shepherd walking sticks. The pupils from the local school helped plant 50 young Z. abelicea trees. They did a fantastic job and were very enthusiastic and dedicated! Each tree was given the name of the pupil who planted it.

Zelkova abelicea: first effects of browsing exclusion

One of the project activities is to monitor on a yearly basis the vegetation and its changes within the fenced pilot plots as compared to the situation outside the fenced plots in browsed areas. The first fenced plots were established in autumn 2014. Therefore, in the spring 2015, the first effects of the fencing measures were already visible. Within the fenced plots, species richness was in average 45% higher than outside. 19 Cretan endemic taxa were recorded inside the fenced plots. 4 orchid species were recorded. Moreover, vegetation cover was visibly higher inside the plots than outside. In average, vegetation cover was 73% higher within the plots than outside. The cover percentage was highest for therophytes (+328%) followed by hemicryptophytes (+166%) and geophytes (+55%) when comparing the fenced plots to browsed areas. In several plots, shoot elongation clearly increased, with some shoots measuring over 40 cm already in mid-June. 

Relict tree of Crete

Based on the thorough research work undertaken in recent years, an international, interdisciplinary and integrated conservation program for Zelkova abelicea has been initiated. The implementation of the project is assumed by the Mediterranean Agronomic Institute of Chania (MAICh) in collaboration with the Forest Directorate of Chania (FDC), Forest Directorate of Rethimno (FDR) and  Forest Directorate of Heraklion (FDH), as well as with local municipal authorities. International coordination and scientific support is assured by researchers and conservationists form the Universitiy of Fribourg (Switzerland) and National and Kapodistrian University of Athens (Greece), from Botanic Gardens Conservation International (BGCI, United Kingdom) and from the Institute of Biosciences and BioResources of the National Research Council in Palermo (Sicily, Italy). Amongst others, new and genetically representative ex situ collections (field living collections as well as seed banks) are being established using seeds and vegetative plant material sampled from all mountain regions where Z. abelicea occurs. Additionally, selected pilot plots have been fenced and are regularly monitored by the team at MAICh and researchers and students of the University of Fribourg. What is more, a range of local and international campaigns and public outreach events have been realized, including scientific seminars, conferences and exhibitions, accompanied by a series of first-rate public outreach materials.