Laudator Temporis Acti

Palaephatus, On Unbelievable Things 35 (pp. 52-53 Festa, tr. Jacob Stern):

Among other ill-considered statements that people have made is this: that the first generation of men was born from ash trees. But it seems impossible to me that human beings sprang from wood. Ash in fact was a man, and the "Ashens" got their name from him, just as the Hellenes were named from Hellen and the Ionians from Ion. Later the whole family died out and the name ceased to be used. The generations of Iron and Bronze never existed either—that too is foolishness.

Καὶ τἄλλα φαύλως εἶπον καὶ τὸ πρῶτον γένος ἀνθρώπων ἐκ μελιῶν γενέσθαι [φασίν]. ἐμοὶ δὲ δοκεῖ ἀμήχανον ἐκ ξύλων ἀνθρώπους γενέσθαι. Ἀλλὰ Μέλιός τις ἐγένετο καὶ Μελίαι ἐκλήθησαν ἀπὸ τούτου, ὥσπερ Ἕλληνες ἀπὸ Ἕλληνος καὶ Ἴωνες ἀπὸ Ἴωνος. ἀλλ᾽ ἐκεῖνο μὲν ἐφθάρη τὸ γένος ὅλον, καὶ δὴ καὶ τὸ ὄνομα ἀπέσβη. σιδηρᾶ δὲ καὶ χαλκῆ γενεὰ οὐδέποτε ἐγένετο, ἀλλ᾽ ἐφλυαρήθη ταῦτα.

Palaephatus is criticizing Hesiod, Works and Days 143-145, here in Hugh G. Evelyn-White's translation:

Zeus the Father made a third generation of mortal men, a brazen race, sprung from ash-trees; and it was in no way equal to the silver age, but was terrible and strong.

Ζεὺς δὲ πατὴρ τρίτον ἄλλο γένος μερόπων ἀνθρώπων
χάλκειον ποίησ', οὐκ ἀργυρέῳ οὐδὲν ὁμοῖον,
ἐκ μελιᾶν, δεινόν τε καὶ ὄβριμον.

Apollonius of Rhodes, Argonautica 4.1641-1642 (describing Talos, tr. R.C. Seaton):

He was of the stock of bronze, of the men sprung from ash-trees, the last left among the sons of the gods.

τὸν μὲν χαλκείης μελιηγενέων ἀνθρώπων
ῥίζης λοιπὸν ἐοντα μετ' ἀνδράσιν ἡμιθέοισιν.

Vergil, Aeneid 8.314-318 (tr. H. Rushton Fairclough):

In these woodlands the native Fauns and Nymphs once dwelt, and a race of men sprung from trunks of trees and hardy oak, who had no rule nor art of life, and knew not how to yoke the ox or to lay up stores, or to husband their gains; but tree-branches nurtured them and the huntsman's savage fare.

haec nemora indigenae Fauni Nymphaeque tenebant
gensque virum truncis et duro robore nata,
quis neque mos neque cultus erat, nec iungere tauros
aut componere opes norant aut parcere parto,
sed rami atque asper victu venatus alebat.

Servius (commenting on Vergil, line 315):

This story arose from the ancient dwellings of men, who before houses were made used to stay in hollow trees or in caves. When they went forth from those places or brought their offspring out, they were said to be born from there.

hoc figmentum ortum est ex antiqua hominum habitatione, qui ante factas domos aut in cavis arboribus aut in speluncis manebant. qui cum exinde egrederentur aut suam educerent subolem, dicti sunt inde procreari.

Statius, Thebaid 4.275-281 (tr. J.H. Mozley):

To him the Arcadians an ancient people, older than the moon and stars, give trusty cohorts; they were born, 'tis said, of the hard trunks of forest trees, when the wondering earth first bore the print of feet; not yet were fields or houses or cities or ordinance of marriage: oaks and laurels suffered rude child-birth, and the shady mountain-ash peopled the earth, and the young babe fell from the pregnant ash-tree's womb.

Arcades huic veteres astris lunaque priores
agmina fida datis, nemorum quos stirpe rigenti
fama satos, cum prima pedum vestigia tellus
admirata tulit; nondum arva domusque nec urbes,
conubiisve modus; quercus laurique ferebant
cruda puerperia, ac populos umbrosa creavit
fraxinus, et feta viridis puer excidit orno.

Lactantius Placidus (commenting on Statius, line 276):

Not because they were truly born from trees, but because they lacked the use of huts and used to wander like cattle. They kept their children either in hollows of trees or in caves of cliffs. Passers-by thought these were children of trees.

non quia de arboribus vere nati sunt, sed quia deerat usus casarum et in morem pecorum vagabantur. filios autem suos aut arborum caveis aut cautium specubus contegebant, quos transeuntes arborum filios aestimabant.

For parallels from Norse mythology, see Michael D.J. Bintley, "Life Cycles of Men and Trees in Sonatorrek," Opticon1826, Issue 6 (Spring 2009) 1-3.