Plant runners are specialized structures that help plants spread and reproduce. RESIN is a sticky, yellowish-brown substance secreted by certain plants, such as conifers, which helps them to spread and reproduce. Tendrils are thin, curling structures that grow from the stems of some plants and help them to climb and spread. Stolons are horizontal stems that grow above or below the ground and produce new plants at their tips. All of these structures help plants to spread and reproduce, making them plant runners.