Initiated by the Scouts of Varna, in the day when we celebrate Earth Hour 2018, Organization of Bulgarian Scouts finished the first stage and started the second one of the project for saving the chestnut trees in some Bulgarian cities. For several years we have been observing that the leaves of chestnut trees are becoming yellow and start falling in the middle of the summer. The Scouts found out that the reason is desizing moth(Cameraria ohridella). The damage, caused by this moths’ larva not only causes the early fall of leaves, but also slows the photosynthesis, therefore weakens the trees and makes them vulnerable to cold, drought, diseases and after few years, the trees die. In the end of the summer, as a first phase of the initiative, the Scouts from Varna, Shumen and Ruse started a common cause to solve this problem in those cities. After detailed research of the possible ways to fight the pest, as a first step we took actions for increasing the population of tinners (Cyanistes caeruleus and Parus major) , who are natural exterminator of those moths. We placed over 200 bird houses and feeders for tinners and provided over a ton of specialized food for the small wild birds. The whole winter we refilled the feeders, which attracted more birds to settle in the affected chestnut trees’ crowns. The larvas are the preffered food for the birds and their babies. In the period the birdies are raised, the grown-up birds catch up to 500 moths daily. To ensure our success, as a second phase of the initiative, we will start using one more biological method for fighting the moths – pheromone traps in the tree crowns. Those pheromones are safe for other species and only attract male moths, which leads to imbalance of correlation between males and females, and therefore decrease the population of the moths. Expected results: 1. Safe a big number of chestnut trees and by this, make our city greener and look better and also improve the quality of the air – more oxygen, less dust; 2. The green crowns of the trees will make shade in summertime and reduce the harmful noise of the city traffic; 3. Trough realization of the project, we will teach more kids and youngsters of love to nature and help them realize better the processes in it; 4. We will popularize environmental and biological methods to protect the plants; 5. We will inform the citizens for the existing problem and will improve their ecological culture.