MUSHROOMS. The mountains of Northern Greece are abundant in fungi. As any mushroom guide would say, most of them are inedible or even lethal. Before you venture out in harvesting, consult a book and people who know. Tip: the Elatia Forest is a Chanterelle paradise after late August. Here's a helpful link of the Greek Mushroom Friends association (facebook page).
FAUNA. Brown bear. Wolf. Fox. Badger. Deer. Lynx. Eagle. These are just a few example of the fauna of the Northern Greek Mountains. The rather endangered species of bear and wolf are very hard to spot and mostly avoid contact with humans. When walking in the mountains you will mostly spot the birds and the crawlers. A very typical example is the fire salamander and various snake species. Do take precautions because Greece features the venomous viper.
FLORA. Most of the mountains but especially the Rodopi Mountain Range, are a botanical paradise. Magnificent species, endangered species, unique species. Spruce, Fir, Pines, Black Pines, Beech Forests, Mixed Forests, forests until your eye is lost in the horizon. Among else, Rodopi Mountain range is the southernmost barrier of the Scandinavian Birch expansion. Also, in Rodopi, Tzena, Pinovo and Voras, you will find the only occurrence of wild blueberry in Greece.