This is from the rig veda praising the quality of the nature of herbs--

HYMN XCVII. Praise of Herbs.

1. HERBS that sprang up in time of old, three ages earlier than the Gods,— Of these, whose hue is brown, will I declare the hundred powers and seven. 2 Ye, Mothers, have a hundred homes, yea, and a thousand are your growths. Do ye who have a thousand powers free this my patient from disease. 3 Be glad and joyful in the Plants, both blossoming and bearing fruit, Plants that will lead us to success like mares who conquer in the race. 4 Plants, by this name I speak to you, Mothers, to you the Goddesses: Steed, cow, and garment may I win, win back thy very self, O man. 5 The Holy Fig tree is your home, your mansion is the Parna tree: Winners of cattle shali ye be if ye regain for me this man. 6 He who hath store of Herbs at hand like Kings amid a crowd of men,— Physician is that sage's name, fiend-slayer, chaser of disease. 7 Herbs rich in Soma, rich in steeds, in nourishments, in strengthening power,— All these have I provided here, that this man may be whole again. 8 The healing virtues of the Plants stream forth like cattle from the stall,— Plants that shall win me store of wealth, and save thy vital breath, O man. 9 Reliever is your mother's name, and hence Restorers are ye called. Rivers are ye with wings that fly: keep far whatever brings disease. 10 Over all fences have they passed, as steals a thief into the fold. The Plants have driven from the frame whatever malady was there. 11 When, bringing back the vanished strength, I hold these herbs within my hand, The spirit of disease departs ere he can seize upon the life. 12 He through whose frame, O Plants, ye creep member by member, joint by joint,— From him ye drive away disease like some strong arbiter of strife. 13 Fly, Spirit of Disease, begone, with the blue jay and kingfisher. Fly with the wind's impetuousspeed, vanish together with the storm. 14 Help every one the other, lend assistance each of you to each, All of you be accordant, give furtherance to this speech of mine. 15 Let fruitful Plants, and fruitless, those that blossom, and the blossomless, Urged onward by Bṛhaspati, release us from our pain and grief; 16 Release me from the curse's plague and woe that comes from Varuṇa; Free me from Yama's fetter, from sin and offence against the Gods. 17 What time, descending from the sky, the Plants flew earthward, thus they spake: No evil shall befall the man whom while he liveth we pervade, 18 Of all the many Plants whose King is, Soma, Plants of hundred forms, Thou art the Plant most excellent, prompt to the wish, sweet to the heart. 19 O all ye various Herbs whose King is Soma, that o’erspread the earth, Urged onward by Bṛhaspati, combine your virtue in this Plant. 20 Unharmed be he who digs you up, unharmed the man for whom I dig: And let no malady attack biped or quadruped of ours. 21 All Plants that hear this speech, and those that have departed far away, Come all assembled and confer your healing power upon this Herb. 22 With Soma as their Sovran Lord the Plants hold colloquy and say: O King, we save from death the man whose cure a Brahman undertakes. 23 Most excellent of all art thou, O Plant thy vassals are the trees. Let him be subject to our power, the man who seeks to injure us.