Sewer laterals are smaller sewer lines that run from an individual's house to the main sewer line. The individual homeowner is responsible for the sewer lateral on their property. Because these lines are smaller and are located under yards they present special maintenance issues.
Tree roots can grow into the laterals which can restrict flow through the pipes and cause a backup into your house. Minor root problems can be controlled and corrected by root control products that are found at hardware stores.
Grease is the primary cause of sewer line blockages. Homeowners should never pour grease down a drain. As the grease cools off it will solidify and can block the lateral. Rather than pouring the grease down the drain, pour it into a jar that can be sealed and then throw it in the trash.