Plutarch, Quaestiones Convivales, book 5, Διὰ τί τὴν μηλέαν ἀγλαόκαρπον ὁ ποιητὴς εἶπεν, Ἐμπεδοκλῆς δ ὑπέρφλοια τὰ μῆλα.? 7:

ἀσθενῆ γὰρ αὐτῶν τὴν ὑγρότητα καὶ γλίσχραν οὖσαν οὐκ ἐᾷ λαβεῖν σύστασιν ὁ ἥλιος, ἂν μὴ μεταβάλλειν ὁ ἀὴρ ἐπὶ τὸ ψυχρότερον ἄρχηται: διὸ καὶ μόνον τοῦτό φησι Θεόφραστος τὸ δένδρον ἐν τῇ σκιᾷ βέλτιον ἐκπέττειν τὸν καρπὸν καὶ τάχιον.