## The Case Study of Chios
### The Mastic Trees in Chios  
Chios is the sixth largest Greek island with 51,390 inhabitants (2011 census) [14] and an area of 842.5 km\({}^{2}\). The terrain is mountainous and arid with most of the largest mountains located in the north of the island (maximum elevation 1297 m). The famous mastic villages and the mastic tree cultivations are located in the south of the island (Figure 1). Mastic cultivation started in the ancient times (around the 5 th century BC) and they produce a rare resin that is largely exported. The mastic trees are the trademark of Chios and a main source of income for many residents of the island.  
The cultivation is only accomplished in the south part of Chios, due to the dry and hot climate. Mastic trees are evergreen shrub with a height of 2-3 m (rarely up to 5) which are found in small flat areas, in valleys, along roadsides or near the villages (Figure 2). In mountainous areas where the ground has a relative slope, there are cultures in steps. In general, the mastic trees have few soil requirements and thrive in barren, rocky, and poor soil. The total cultivated area of mastic is 20 km\({}^{2}\), which represents approximately the 12% of the total cultivated area of the island. The 2 million mastic trees that are estimated to be in this area, are engaged with 4500 agricultural families and therefore are very important for the local economy.  
Figure 1: Chios island and the 24 ”Mastichochoria” (mastic villages). In red color, the AIGAIA ZEUXI project area location at the map and the wind farms layout.  
The magnetic trees live more than 100 years, but they provide resin from their 5 th year until their 70 th. The care of the mastic groves extends over the whole year, since they grow in summer, but during the winter months it is necessary to prune and thin the branches. Around June, the surrounding ground is cleaned of weeds and it is spread with sieved white soil. This avoids the resin dripping and drying into the brown soil or to darken. Then, between July and October, the harvesting of the resins takes place.  
Though there are many varieties of mastic trees growing throughout the Mediterranean, it is only in the Greek island of Chios that the production of gum mastic occurs. There was no successful development elsewhere, in the continental or insular Greece or even in the neighboring coasts of Turkey. Within the European Union, mastic production in Chios is granted a protected designation of origin. Originally a liquid, mastic is sun-dried into drops of hard brittle translucent resin. When chewed, the resin softens and becomes a bright white and opaque gum. The flavor is bitter at first, but after some chewing, it releases a refreshing, slightly pine or cedar-like flavor. Mastic appears to have a myriad of applications ranging from the medicinal to the functional, including use as a stabilizer in paints and making varnishes, especially for musical instruments. It has been used in the production of tires, aromatic soaps, insecticides, electrical insulators, and chewing gum, as well as quality spices, alcoholic beverages, and sweets. The total annual production is 150 tn and 90% of the product is exported. With a price range of 180-250 EUR/kg, this exclusive product is considered as a major part of the local economy.