Pumpkin Pie Poem by Ima Ryma

My main component - native one
From America, Greek to me,
As in melon cooked by the sun.
Thanks to smart folks, I came to be,
And now am a Thanksgiving must,
And popular in poem and song.
I am an icon people trust
To spice the holidays along.
The world's largest of me was made
Twenty ten, Bremen, Ohio,
Thirty eight hundred pounds I weighed,
Twenty feet diameter - whoa!

What a piece of work! What am I?
I, of course, am a pumpkin pie.