Bhagavad Gita Chapter 15, Verse 2

अधश्चोर्ध्वं प्रसृतास्तस्य शाखा गुणप्रवृद्धा विषयप्रवालाः | अधश्च मूलान्यनुसन्ततानि कर्मानुबन्धीनि मनुष्यलोके ||

adhaś cordhvaṁ prasṛtās tasya śākhā guṇa-pravṛddhā viṣaya-pravālāḥ adhaś ca mūlāny anusantatāni karmānubandhīni manuṣya-loke

Its branches spread upward and downward, nourished by the gunas. The sense objects are the buds. Its roots extend downward into the human world, binding through karma.

Krishna details how the ashvattha tree works: 'Adhaś cordhvaṁ prasṛtāḥ'—its branches spread both upward and downward. But here's the key: 'Guṇa-pravṛddhāḥ'—nourished by the gunas. The three modes of nature (sattva, rajas, tamas) feed this tree. 'Viṣaya-pravālāḥ'—sense objects are the buds. Every desire, every attachment, every sensory experience you crave becomes a bud that grows into a branch. The tree thrives on your desires. 'Adhaś ca mūlāny anusantatāni karmānubandhīni manuṣya-loke'—the roots extend downward into the human world, binding you through karma. Every action creates karma, and karma binds you to the tree. The more you act with attachment, the more the roots grow. The more the roots grow, the more entangled you become. This is the cycle: gunas feed the tree, sense objects are buds, actions create karma, karma binds you to the tree, and the tree keeps growing. To break free, you must stop feeding it—detach from the gunas, transcend sense objects, act without attachment to results.