have straws in (one's) hair

obsolete To be insane or mentally deranged; to be or have been a patient of a mental institution. The more sensationalist newspapers have taken to saying he has straws in his hair, but I think that he knew full well the scope and impact of his crime. Wouldn't you have straws in your hair if you had to listen to such persistent, vexatious comments? If you continue to dwell upon these failures and setbacks, you'll have straws in your hair before long.

straws in (one's) hair

obsolete A state of insanity or mental derangement. An allusion to patients of mental institution, which used to have floors covered in straw. Such persistent, vexatious comments are enough to put straws in one's hair. Do not dwell upon these failures and setbacks; you must march forward, or else you risk ending up with straws in your hair.

straws in your hair

a state of insanity.

In former times, the floors of mental institutions were covered with straw, and so having straw in the hair came to be regarded as a characteristic of a deranged person.