OTTAWA — If you live in Ottawa, start dragging your tree limbs to the curb as quickly as possible. City crews have started picking up limbs and branches, said Andy Haney, public works director. The limbs should be stacked parallel to and as closely as possible to the street curb to speed up the collection and to minimize damage to lawns, he said. Crews will make at least two complete rounds of the city. The clean-up should be completed by July 2, he said. That will allow homeowners two weekends to clean up their yards, he said. Because there’s not much space, crews can’t pick up limbs in alleys, he said.