Does anyone know how (if) an image that is added to a painting can be resized?

Eg. I was working on a Painter X "painting" of a landscape. In Photoshop, I had several trees saved in one file, each on it's own layer. I opened the photoshop file with Painter, selected a tree layer, and was pleased that I could drag it into the new painting. Perfect!

But now I can't see how to resize the tree to fit. Looked all over the help menu. In photoshop, I would select the tree, then edit - transform - size.

Anyone know how to do this from within Painter X?
Thanks