1. School of Life Sciences; Keele University; Staffordshire UK
2. College of Education for Pure Science; University of Mosul; Nineveh Iraq
3. Institute of Dendrology; Polish Academy of Sciences; Kórnik Poland
4. Faculty of Biological Sciences; University of Zielona Góra; Zielona Góra Poland
5. Poznań University of Life Sciences; Department of Forest Management; Poznań Poland
6. Department of Botany; University of Benghazi; Benghazi Libya