Apart from his celebrated creativity when it comes to ways of describing drunkenness, Wodehouse is also fond of a number of expressions that indicate lunacy, such as potty, dotty, loony, loopy, bugs, non-compos, mad as a coot, crazy as a bed bug, off one's nut/onion/rocker; asylums are "the loony bin," "the padded cell," and "some sort of home;" known symptoms are keeping rabbits in your bedroom, believing you're a loaf of bread or a tea-pot, throwing flower-pots, breaking furniture with a poker, etc.
One of his favorite manifestations is sticking straws in your hair:
Rupert Baxter had not yet begun to stick straws in his hair, but he seemed on the verge of that final piece of self-expression. (Summer Lightning, ch. 18)
The phrase has a long and interesting history. This post in the excellent Word Histories blog collects a variety of examples that prove beyond doubt that the equation "straws in hair = lunatic" was a theatrical convention in the second half of the nineteenth century, with Shakespeare's Ophelia as its archetype. Among other important references, this phrase from a sketch in Punch, January 1842 shows that the convention was established well enough to be parodied: "SCENE.—GREEN ROOM. OPHELIA discovered with straws in her hair, and sucking a Crevilli lozenge."
However, I cannot agree with the writer's statement that "It is often—and erroneously—said that it originated in the notion that patients in mental asylums got straw from the floor caught up in their hair" and that the phrase actually originated in these representations of Ophelia and need not be traced further back. Origin stories of this type are certainly suspect, especially when they are so picturesque, and it is right and proper to ask for documentary support before accepting them, since nine times out of ten they are merely a product of the imagination. But in this case there is actually enough evidence to argue that the theatrical usage derived in turn from the sad realities concerning asylum inmates. More precisely, long before the first records of straws conveying lunacy on the stage, we find it associated with Bedlam inmates, in the form of bedding, hair ornaments and as straw crowns that implied the madman believed himself a king.
J. Kromm in The Art of Frenzy. Public Madness in the Visual Culture of Europe, 1500-1850 surveys a long tradition of straw in the representation of madness in art and caricature:
Straw had appeared along with a range of natural ornaments, including weeds and feathers, traditionally given to roaming fools in continental art, and was adapted to the incarcerated madman over the course of the seventeenth century in Jacobean plays such as John Fletcher's The Pilgrim (1621). In these circumstances, straw was a coded reference to the inmate's confined and regressed status, because loose straw was the only bedding used in Bethlem or other establishments for such extreme cases. The association with straw was also widely regarded as a clear sign of maniacal agitation, and Swift's description of the mad soldier in "The Digression on Madness" reinforced this connection. Both the institutional element and the concentration on straw differentiate this usage from the situation of Ophelia, whose flower-entwined hair called attention to her past distracted wandering and preoccupation with natural and sexual imagery, and who, of course, never suffered from a combative form of mania. But confined madwomen, like the one in the Rake plagiaries and in Pine's depiction, wear their hair dressed in straw in a motif that combines incarceration with female vanity. When Fletcher's playscript was published in 1711, its frontispiece by Francois Boitard gave prominence to straw as a floor covering and hair ornamentation for the regressed inmates, in particular for the play's "Mad Englishman," while the mad scholar and mad parson are identified by the paraphernalia of their respective professions. (pp. 131-133)
[J. Swift's passage in section IX of Tale of a Tub (1696) reads: "Is any Student tearing his Straw in piece-meal, Swearing and Blaspheming, biting his Grate, foaming at the Mouth, and emptying his Pispot in the Spectator's Faces? Let the Right Worshipful, the Commissioners of Inspection, give him a Regiment of Dragoons, and send him into Flanders among the Rest."]
As we can see, Kromm at this stage explicitly separates the symbolism of Ophelia's flowers from that of the madman's straw in visual arts. She does not address the question of whether straw was also used in the latter context in the period covered by her study (1500-1850), dedicated to the pictorial arts, but so far the only examples found are from the Victorian period, like Hamlet above or King Lear, as we will see below.
One of several graphic examples analyzed by Kromm, The Hospital for Lunatics (1789) attributed to Thomas Rowlandson, illustrates the straw-crown motif in political satire. "Naked below the waist, [the statesman William] Pitt sits atop a chamber pot and sports a straw scepter and crown. The cause of his condition is scrawled above: he 'went mad supposing himself next heir to a Crown.'"
Moving on to literature, we can find examples since the mid-1700s at least:
"Well—of all plagues which make Mankind their Sport,
Guard me, Ye Heav'ns! from that worst Plague—a Court.
'Midst the mad Mansions of Moor-fields, I'd be
A Straw-crown'd Monarch, in mock Majesty;
Rather than Sov'reign rule Britannia's Fate,
Curs'd with the Follies and the Farce of State;
Rather in Newgate-Walls, O! let me dwell,
A doleful Tenant of the darkling Cell,
Than swell in Palaces the mighty Store
Of Fortune's Fools, and Parasites of Pow'r;
Than Crowns, ye Gods! be any State my Doom,
or any Dangers, but—a Drawing Room."
But after all, so little do they know, who really seek Knowledge, & so much less do they who only play with these natural Experiments, that I think Nucleus is very little better than King Pepin in Bedlam, who is always wearing a Straw Crown.
(The Weekly Amusement, June 16, 1764)
In short, they talk'd with serious air
(Rating him madder than March hare)
Of shutting him in some dark cell,
With straw-crown'd emperors to dwell;
Which made him almost mad as those
Who daily drank th' enchanted dose.
("The Influenza," The Gentleman's Magazine, April 1777)
Why, sometimes you wou'd imagine, from the wooden scepters, straw crowns, and such like trumpery, that Bedlam was transported from Moorfields to the spot you now stand upon.
(All the World's a Stage, 1777)
On calm Religion's prop reclin'd at last,
I'll drown affliction with futurity;
Like the poor maniac fool, forget the past,
Weave my straw crown, and laugh at misery.
(Sonnet XII, Savillon's Elegies, 1795)
Never so happy as when he can escape from this blessing, he dozes away as much of it as he can in sleep—or blows out his highly vaunted brains every evening with a bottle of port wine—or tells you, with a paviour's s sigh, that the happiest man is the laughing lunatic who finds his straw-crown and jointstool throne a most delightful exchange for all the vanity and vexation of irrational reason.
("Advantages of having No Head," New Monthly Magazine, 1822)
The earliest use of the literal expression "to stick straws in one's hair" is closely linked with this tradition:
But the insane have, perhaps, no attribute more in common than that of superweening self-esteem. The maniac who has been removed from a garret, sticks straws in his hair and calls them a crown.
(E. Bulwer Lytton, A Strange Story, 1861)
Lunatics always stick straws in their heads, vide the drama passim.
(E. H. Yates, Dr. Wainwright's Patient, 1871)
As for believing in ghosts, that's a hard thing to say yes or no to. Say yes, without reserve, and ye may as well stick straws in your hair and set up a private Bedlam out of hand at once.
(D. C. Murray, Rainbow Gold, 1885)
Yates' quotation brings us back to stage-land, i.e. the fact that an actor wears straws in his hair immediately tells the audience that the character is a lunatic. Edward Booth's Prompt Book for Shakespeare's King Lear (1878), which can be taken as a guide to how it was staged at the time, mentions that Edgar, who has disguised himself as a madman, during his encounter with Lear in III.6 accompanies the lines "For with throwing thus my head, Dogs leap the hatch, and all are fled" with this stage direction: "Throws straw crown to L" (p. 73); it is natural to associate with the same tradition the passage in IV.4 where the mad Lear replaces the crown he has divided between his daughters with one made of flowers and weeds:
CORDELIA.
Alack, 'tis he. Why, he was met even now,
As mad as the vexed sea, singing aloud,
Crowned with rank fumitor and furrow-weeds,
With burdocks, hemlock, nettles, cuckoo-flowers,
Darnel, and all the idle weeds that grow
In our sustaining corn.
Still, it would probably be unwarranted to say that Shakespeare had this Bedlam imagery in mind when he described either Lear or Ophelia wearing flowers and/or weeds in their hair. What is beyond doubt is that the association between madness and straw was already strong in the arts in the 17th century, and it is reasonable to deduce that Victorian drama inherited this tradition. I tend to believe that this convention was in turn responsible for the survival of the phrase in common language, as we find it in Wodehouse (who, despite being a man of the theater, never hints at a theatrical origin).

