All attempts at showing earlier versions of this seem to ignore one of our (Britain's) better writers. In Othello, Desdemona sings about the wearing of the green willow. "Green willow must be my garland".
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DESDEMONA: My mother had a maid call'd Barbary;
She was in love, and he she loved proved mad
And did forsake her. She had a song of "willow";
An old thing 'twas, but it express'd her fortune,
And she died singing it. That song tonight
Will not go from my mind; I have much to do
But to go hang my head all at one side
And sing it like poor Barbary. Prithee, dispatch.

EMILIA: Shall I go fetch your nightgown?

DESDEMONA: No, unpin me here.
This Lodovico is a proper man.

EMILIA: A very handsome man.

DESDEMONA: He speaks well.

EMILIA: I know a lady in Venice would have walked barefoot to
Palestine for a touch of his nether lip.

DESDEMONA [Sings.]:
"The poor soul sat sighing by a sycamore tree,
Sing all a green willow;
Her hand on her bosom, her head on her knee,
Sing willow, willow, willow.
The fresh streams ran by her, and murmur'd her moans,
Sing willow, willow, willow;
Her salt tears fell from her, and soften'd the stones--"

Lay by these--

[Sings.] "Sing willow, willow, willow--"

Prithee, hie thee; he'll come anon--
[Sings.]

"Sing all a green willow must be my garland.
Let nobody blame him; his scorn I approve--"

Nay, that's not next. Hark, who is't that knocks?

EMILIA: It's the wind.

DESDEMONA [Sings.]:
"I call'd my love false love; but what said he then?
Sing willow, willow, willow.
If I court moe women, you'll couch with moe men--"
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This seems also to be a fore-runner of Gilbert & Sullivan,
"On a tree by a river a little tom tit
Sang "Willow, tit willow, tit willow""

Nigel