bhagavan harir avyayah
vanaspatin osadhis ca
sasarjorjam isam vibhuh
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead, Sri Hari, is the master of all living entities, including all the prajapatis, such as Lord Brahma. Because He is the all-pervading and indestructible master, He has created all these trees and vegetables as eatables for other living entities.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Soma, the predominating deity of the moon, reminded the Pracetas that this vegetation had been created by the Lord of lords to provide food for everyone. If the Pracetas tried to kill them off, their own subjects would also suffer, for trees are also required for food.