Leaf and Plugin

I updated my headway theme in wp, but it messed up my pages. So I went back to the old headway theme that was previously on there before I updated, but now I get the following message:

“The requested leaf type does not exist. Please re-activate the plugin if you wish to use this leaf again.”

Anyone know what plugin their referring to?

I backed up everything in WP before I updated the site with the most recent theme.

Thanks.