“In Spring all trees become pregnant”
Source: De architectura (The Ten Books On Architecture) (~ 15BC), Book II, Chapter IX "Timber" Sec. 1
Context: In Spring all trees become pregnant, and they are all employing their natural vigor in the production of leaves and of the fruits that return every year. The requirements of that season render them empty and swollen, and so they are weak and feeble because of their looseness of texture. This is also the case with women who have conceived. Their bodies are not considered perfectly healthy until the child is born.
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Vitruvius 203
Roman writer, architect and engineer -80–-15 BCRelated quotes

“In the mountains a night of rain,
And above the trees a hundred springs.”
As quoted in Lin Yutang's My Country and My People (1936), p. 247

“I want to do with you what spring does with cherry trees.”
Quiero hacer contigo lo que la primavera hace con los cerezos.
"Every Day You Play" (Juegas Todos las Días), XIV, p. 35.
Variant: I want
To do with you what spring does with the cherry trees.
Source: Veinte Poemas de Amor y una Canción Desesperada (Twenty Love Poems and a Song of Despair) (1924)

An argosy of fables, "The Leaves and the Roots" p. 398
The Fables (1883)

"Carric-thura". Compare:
Τὼ δ᾽ ἄνεῳ καὶ ἄναυδοι ἐφέστασαν ἀλλήλοισιν,
ἢ δρυσίν, ἢ μακρῇσιν ἐειδόμενοι ἐλάτῃσιν,
τε παρᾶσσον ἕκηλοι ἐν οὔρεσιν ἐρρίζωνται,
νηνεμίῃ· μετὰ δ᾽ αὖτις ὑπὸ ῥιπῆς ἀνέμοιο
κινύμεναι ὁμάδησαν ἀπείριτον.
The pair then faced each other, silent, unable to speak, like oaks or tall firs, which at first when there is no wind stand quiet and firmly rooted on the mountains, but afterwards stir in the wind and rustle together ceaselessly.
Apollonius of Rhodes, Argonautica (3rd century BC), Book III, lines 967–971 (tr. Richard Hunter)
The Poems of Ossian

Stanzas to Augusta (1816), reported in Bartlett's Familiar Quotations, 10th ed. (1919).

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 526.