Irfan Husain, 55, a former employee at a power utility in the Middle East, moves a newly-grown Azadirachta Indica seedling on his roof in Karachi, Pakistan June 17, 2021. Karachi is a sprawling port city of some 17 million people, where breakneck expansion of roads and buildings means there is less and less space for trees and parkland. REUTERS/Akhtar Soomro SEARCH "SOOMRO PAKISTAN FOREST" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.