Climate change resilience is the capacity to prepare for, respond to and recover from the impacts of hazardous climatic events while incurring minimal damage to societal wellbeing, the economy and the environment. Despite of several efforts taken by the Government and Non-governmental organization in reducing the impact of climate change like promoting and planting of trees with in the municipality, its observed that there were no proper strategies for monitoring of those planted trees. Therefore, mapping of trees using open-source tools in Morogoro municipality was way towards monitoring of planted trees. The project was done under SMCoSE Youthmappers with the aim of enhancing planning and monitoring of planted trees from afforestation campaigns that address climate action which enable to meet the sustainable goals number 13 (Climate action). This project was having three objectives which include Planning, Planting and Monitoring. Through planning we were able to collect data and identify places that afforestation is needed most. All areas where there was the scarcity of trees were identified. After identifying those places the planting of trees followed. In planting, together with tree planting campaigns we were conducting afforestation activities. However, in monitoring with the help of open-source mobile tracking applications we monitor the afforestation activities because this will make easy to track the location of the tree and also easy to monitor those trees. The use of open-source tools like Open Data Kit (ODK) was used to collect coordinates of the trees around Morogoro municipality. The collected data were entered in the GIS software (QGIS) in order for performing data classification, visualization and map creation. Over 440,000 tree coordinates were collected and then those data were entered in the QGIS for doing data cleaning and visualization. After the data collection, cleaning and visualization, the maps were produced through these maps enable to show where the trees allocated and the distribution of those trees, also, the area where trees were planted. Also, through these maps enable to locate area where need more afforestation. So, the use of open-source tools enables in the process of monitoring of the planted trees, this make easy to keep the records of places where tree planted so as make it easy to take care of those trees and to ensure that trees are growing well.