Form to Content

Haiku

Ponytails are fine.
The tying back of impulse
That would rather fly.

Limerick

"There once was a teacher named Rumbly
Who had a strange noise in her tumbly.
She had armpit hair,
And made sounds like a bear,
Her skin is very crumbly."

(A limerick I wrote in grade five. Ms. Rumbly is based on an actual teacher I had, Ms. Rumley, who I just so happened to despise. I got in a lot of trouble for writing this.)

Upon writing the two poems above, I found that the content and tone changed drastically depending on the form. The haiku seems to be much more understanding and accepting of  varying content matters - one can write a haiku about anything; it accepts a wider variety of subjects than the limerick, which, mainly because of its rhyme scheme and cadence, demands a lighter subject. The tone changes as the form varies.
I originally set out to write a limerick about cancer or sex to see if I could write a limerick about something that needs to be taken in a more serious context, but the sing-song cadence of it made that virtually impossible/ disrespectful.
The length demanded by both haikus and limericks makes it so that the content must be precise. The form must accent and compliment the content, because the poems are so short, there is no room for air if the full impact of the piece is to be conveyed and accepted by readers.
 Rhyme scheme, cadence, placement of lines on a page (demonstrated well by the renowned poet e.e. cummings), length, and other things that convey form all have an impact on the content of a poem based on how efficiently and accurately it is to be conveyed to readers, how well the author can tailor his writing to fit the demands of a set form (or lack thereof), and the tone that is to be set by a pre-supposed rhyme scheme, cadence. etc.