What's in a word?

Another one of my favorite poems.(And, no, I am not overdoing the whole poems thing, thankyouverymuch.) 

Say "bird,"
and a sparrow appears
inside you and ruffles
its feathers

Say "cardinal,"
and the bird turns red.
Suddenly it is winter.
With a lot of snow. And look!
There are sunflower seeds
in the feeder
--
Siv Cedering