AN important part of urban planning is the provision of green parks and open spaces, even small tree plantations such as the Arroceros area near the Pasig River where trees, both wild and native varieties, are cared for and allowed to grow. The place is called the “lungs” of Manila because it filters the carbon dioxide emitted by factories and vehicles and turns it into oxygen. Previous mayors of the city—Alfredo Lim, Joseph Estrada and Isko Moreno—may be credited for their serious efforts at establishing new parks and making the city’s plazas attractive again, or refurbishing old ones to make...