Weisman's claim pertains to the fact that the city would be left in ruins without people to maintain the plants. In the excerpt, it states - "city maintenance usually shows up, kills the weeds, and fills the fissures"- which further proves my point. The lack of people would lead to the sewers being clogged, cracks expanding and allowing more plants to grow, trees finding root and covering the city with ever expanding canopies.
