Abstract
Community service is one of the duties that must be carried out by every lecturer in Higher Education as one aspect of Tri Dharma University. This community service was titled "The Production of F0 Oyster Mushroom Seeds (Pleurotus ostreatus), The Post-Harvest Handling, and The Utilization of Baglog Waste into Compost" which involved two partners. Partner 1 was in Pegajahan Village, Pegajahan Sub-District who experienced problems with the availability of high-quality F0 and F1 seeds and low production in terms of quality and quantity. Partner 2 was in Blok H Village Dolok Masihul Sub-District, Serdang Bedagai Regency who had a lack of knowledge about post-harvest handling and composting from oyster mushroom baglog waste. Solutions offered for both partners were: (1) transfer of knowledge, such as lectures and discussions; (2) training; and (3) mentoring about the cultivation of F0 and F1 oyster mushrooms. Goals and targets of this activity were: (1) the communities or the farmer groups were able to produce and cultivate F0 and F1 oyster mushrooms, so they did not need to buy F0 and F1 seeds from other regions and can fulfill the market demand; and (2) Partner 2 was able to make compost from oyster mushroom baglog waste and various processed food from oyster mushroom to increase their income. The results of this activity have provided benefits to Partner 1 regarding their ability to produce F0 and F1 seeds, ability to process post-harvest oyster mushrooms into several types of food to increase its selling value, and ability to make compost from baglog waste which can be used for plants to overcome environmental pollution and to increase Partner 2’s income.