While the New York City sidewalk law requires landowners to take care of the city-owned sidewalks that adjoin their property, the courts have made it clear that this duty does not extend to tree-wells and curbs, which are not part of the sidewalk. In a recent case in New York County, this distinction proved more difficult to define in practice than one might suspect. A pedestrian tripped on a defect in the concrete but the court was unable to decide on summary judgment whether the defect was in the sidewalk or in the curb. Photos of the defect and an affidavit from an engineer did nothing to solve the problem, so it goes to a jury. It seems that there are curbs and there are curbs. Some are separate and distinct curb stones, while others are just an extension of the concrete that was poured when the sidewalk was built. So far tree wells remain clear and easy to define but not so the curb. http://www.courts.state.ny.us/reporter/3dseries/2009/2009_50194.htm