art from invasives

i'm involved in an organization in dc, we are going to run an 'art from invasive species' series of workshops. spoon-carving, mulberry bark paper, koto resonator carving.
looking for other ideas, who's got 'em?

I had an idea that could be adapted. My original idea was to grow mulberry and keep cutting it and scarring the trunk until it was a knarly masterpiece, but this will take years. Another idea is finding multiple mulberry or other trees that just kept getting cut year after year and cutting out the stumps and making carvings. I found a fence line stump that looked like a human form one time, it was art.

Paper mache from the pulp of just about any invasive leafy plant. I haven't actually tried this, but if you can make paper, you can make paper mache. Just add glue.

Our local invasive is European Buckthorn(Rhamnus), the wood is bright orange and I've heard sought after by woodworkers.

Sharon Kallis does a lot of art projects with natural materials, many of them invasives...she was a guest author here at permies not too long ago. This is her web site link http://sharonkallis.com/

"With a “one mile diet” approach to sourcing art materials, Sharon works to discover the inherent material potential in a local landscape."