James Reveal, Professor Emeritus, Botany University of Maryland
Recorded at Packer Meadows in the Clearwater Forest near Lolo Pass
on the crest of the Bitterroot Range, July 3, 2003.
Lewis's plant press was probably in the form of a book. A very large book, probably twelve by eighteen inches. It may or may not have been bound on the one side. This is a traditional plant press that you find in China. It is made out of bamboo and consists of a flat strong surface that specimens can be placed in. Lewis used paper much like you used as a youngster in kindergarten. A kind of construction paper. It was folded in half and the specimen placed in between. Now, Lewis's paper was twelve by eighteen when folded, this is half that. You'll notice that the paper is absorbent. This way the specimen's moisture would go into the paper, be absorbed by the paper, and then the specimen could be slowly dried. But in drying, everyday Lewis had to open his press, remove the old pages that were damp, lay them in the sunshine, allow them to dry, and move his plants into new paper so they would continue to dry.
Modern botany is quite different from Lewis's day. We use very large presses and in a good operation you'll run three to five presses, filling each during the course of a day. Each press consists of about room for one hundred different specimens. We are able to dry these very rapidly using what is known as a Holmgren drying frame, by putting a heat source underneath, a coleman stove or electric light bulbs. The heat rises through the corrugates, the holes in the corrugates, and will dry plants overnight, if not during the course of twenty-four hours.
Supported in part by a grant from the Idaho Governor's Lewis and Clark Trail Committee.