On Van Gogh's "Mulberry Tree"

This is the one that must be perceived orally.
A friend years ago told me about this friend of hers
who got thrown out of a museum for licking a painting.
And yeah, we can't have them all digested by art
freak saliva, I'm not saying let him lick it -
but I love him and I can't get down with anyone
who doesn't feel bolder for his dignity.
I wouldn't do it and anyway The Mulberry Tree
is covered with glass, but I can only see it
with the tip of my tongue, from the muddy yellow blob
tinged with blue at the center, to the lightning tentacle
branches and the flat scrapes of cerulean
that make up the sky in the upper right corner.