Flora of the Pacific Northwest, Hitchcock and Cronquist, 7th edition, University of Washington Press, 1973.
The Reference Manual of Woody Plant Propagation, Dirr and Heuser, Varsity Press, 1987.
Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic Press, 1998.
Seed Germination Theory and Practice, Deno, Norman, Penn State University, 1993.
Glacier National Park Native Plant Nursery Propagation Records, unpublished.