Matsya Purana — Rites for Consecrating and Celebrating Trees
यश्चैकमपि राजेन्द्र वृक्षं संस्थापयेन्नरः सो ऽपि स्वर्गे वसेद्राजन् यावदिन्द्रायुतत्रयम् //
yaścaikamapi rājendra vṛkṣaṃ saṃsthāpayennaraḥ so 'pi svarge vasedrājan yāvadindrāyutatrayam //
O best of kings, whoever establishes even a single tree—such a man too, O king, dwells in heaven for as long as three ayutas of Indra, an exceedingly vast span measured in Indra-years.
This verse does not discuss Pralaya; it focuses on dharma through public welfare—specifically the spiritual merit (puṇya) gained by establishing a tree.
It frames tree-planting as a high-value righteous act. For kings, it supports rajadharma through public benefit (shade, fruit, ecological stability); for householders, it is an accessible act of dana-like merit with long-lasting results.
No direct Vāstu or temple rule is stated, but the verse aligns with Purāṇic public-works ethics: establishing enduring supports (like trees) is treated as a meritorious foundation for settlements, roadsides, groves, and sacred precincts.