"The Blessed Lord said,
‘They speak of an eternal fig tree
with root above and branch below,
of which the leaves are Vedic chants;
he who knows this knows the Vedas.
‘Fed by qualities, its branches spread out
above and below, its shoots are sense objects,
with roots stretched out extensively beneath it,
which, in the world of men, give rise to action.
‘Here in the world, its form is imperceptible,
neither its end, duration, nor beginning;
with the firm axe of non-attachment,
having chopped down this holy strong-footed fig tree,
‘only then is that place to be sought after
from which none may return of those who reach it ....
(15:1-4; Norton Critical Edition, trans. Gavin Flood [2014], 72-73)
I found these two images of the inverted ashvatta (sacred fig) online. The one at the top is a flip appropriation of an 1836 engraving of a peepal, posted on someone's Facebook page. The one at at right is a devotional image from a Hindu magazine. The ashvatta is clearly known to grow in both directions, paradoxical and profound - like Krishna:
'Of trees, I am the sacred fig ....(10:24)