Today I tried out the thinner kraft paper on the other side of landscape behind the cottage. It worked better than I imagined. This painter's masking paper, about $1.99 for a generous length of a 12" wide roll, was the perfect material. I sopped liquid starch onto paper towel-sized lengths and then wrung each sheet out like a sponge, opened it up flat and then laid it down over clumps of newspaper that had been hot glued down onto cardboard. I'll put the fan on the area overnight to speed the drying before further layers. I plan on putting down many layers of mache before painting the finalized surface with FlexAll© flexible cement.
It was hugely quicker to cover the large landscape area than it would have been doing it in small strips that the denser carpenter's paper would have required. This thinner paper remained as strong as fabric when wet with starch and allowed for a lot of manipulation without tearing. It molded to the tree shapes like butter, something that the heavier brown paper could not do. I think a mixture of the two weights, in alternating layers, would be the ideal method of making the set's hard-shell while keeping its sculpture shape articulate.
I also added a little bulk in spots to branches on the house side of the tree.
...The furious part of this post is what's going to happen when Himself gets home from work to find this is all I've done today--even as that *print design deadline* is approaching, still, and yet again. (argh. Please help me think of a good, fun solution for this project in your mind's eye!)