Śatapatha Brāhmaṇa ("of a hundred paths") 6.6.3.3

6.6.3.3

te hocuḥ | hanta yaiṣu vanaspatiṣūrgyo rasa udumbare taṃ dadhāma te yadyapakrāmeyuryātayāmā apakrāmeyuryathā dhenurdugdhā yathānaḍvānūhivāniti tadyaiṣu vanaspatiṣūrgyo rasa āsīdudumbare tamadadhustayaitadūrjā sarvānvanaspatīnprati pacyate tasmātsa sarvadārdraḥ sarvadā kṣīrī tadetatsarvamannaṃ yadudumbaraḥ sarve vanaspatayaḥ sarveṇaivainametadannena prīṇāti sarvairvanaspatibhiḥ saminddhe

They said, 'Come, let us lay into the udumbara tree whatever pith, whatever vital sap there is in these trees: were they then to desert us, they would desert us worn out, like a milked-out cow, or like an ox that has been (tired out by) drawing (the cart).' Accordingly they laid into the udumbara tree what pith and essence there was in those trees; and on account of that pith it matures (fruit) equal to all the (other) trees: hence that (tree) is always moist, always full of milky sap,--that udumbara tree, indeed, (being) all the trees, is all food: he thus gratifies him (Agni) by every kind of food, and kindles him by all trees (kinds of wood).