Srimad Bhagavatam Canto 03, Chapter 09, Text 16

SB 3.9.16

yo va aham ca girisas ca vibhuh svayam ca
 sthity-udbhava-pralaya-hetava atma-mulam
bhittva tri-pad vavrdha eka uru-prarohas
 tasmai namo bhagavate bhuvana-drumaya
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
Your Lordship is the prime root of the tree of the planetary systems. This tree has grown by first penetrating the material nature in three trunks — as me, Siva and You, the Almighty — for creation, maintenance and dissolution, and we three have grown with many branches. Therefore I offer my obeisances unto You, the tree of the cosmic manifestation.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
The cosmic manifestation is grossly divided into three worlds, the upper, lower and middle planetary systems, and then it broadens into the cosmos of fourteen planetary systems, with the manifestation of the Supreme Personality of Godhead as the supreme root. Material nature, which appears to be the cause of the cosmic manifestation, is only the agency or energy of the Lord. This is confirmed in Bhagavad-gita (9.10): mayadhyaksena prakrtih suyate sa-caracaram. “Only under the superintendence of the Supreme Lord does material nature appear to be the cause of all creation, maintenance and dissolution.” The Lord expands Himself into three — Visnu, Brahma and Siva — for maintenance, creation and destruction respectively. Of the three principal agents controlling the three modes of material nature, Visnu is the Almighty; even though He is within material nature for the purpose of maintenance, He is not controlled by the laws of material nature. The other two, Brahma and Siva, although almost as greatly powerful as Visnu, are within the control of the material energy of the Supreme Lord. The conception of many gods controlling the many departments of material nature is ill conceived of by the foolish pantheist. God is one without a second, and He is the primal cause of all causes. As there are many departmental heads of governmental affairs, so there are many heads of management of the universal affairs.
Due to a poor fund of knowledge, the impersonalist does not believe in the personal management of things as they are. But in this verse it is clearly explained that everything is personal and nothing is impersonal. We have already discussed this point in the Introduction, and it is confirmed here in this verse. The tree of the material manifestation is described in the Fifteenth Chapter of Bhagavad-gita as an asvattha tree whose root is upward. We have actual experience of such a tree when we see the shadow of a tree on the bank of a reservoir of water. The reflection of the tree on the water appears to hang down from its upward roots. The tree of creation described here is only a shadow of the reality which is Parabrahman, Visnu. In the internal potency manifested in the Vaikunthalokas, the actual tree exists, and the tree reflected in the material nature is only the shadow of this actual tree. The impersonalists’ theory that Brahman is void of all variegatedness is false because the shadow-tree described in Bhagavad-gita cannot exist without being the reflection of a real tree. The real tree is situated in the eternal existence of spiritual nature, full of transcendental varieties, and Lord Visnu is the root of that tree also. The root is the same — the Lord — both for the real tree and the false, but the false tree is only the perverted reflection of the real tree. The Lord, being the real tree, is here offered obeisances by Brahma on his own behalf and also on behalf of Lord Siva.
Srimad Bhagavatam Canto 03, Chapter 09, Text 15
Srimad Bhagavatam Canto 03, Chapter 09, Text 17