The study of germination of seeds of trees and shrubs was continued during the years 1922 and 1923. The seeds considered were very lightly covered, and left upon the ground out of doors to winter; the season was moderate, both in temperature and in snowfall. The seeds seemed in excellent condition when lifted in the spring. Before they were planted in the greenhouse, all seeds were scratched, a small file being used to break the outer seed coat.
Proceedings of the Iowa Academy of Science
©1923 Iowa Academy of Science, Inc.
Pammel, L. H. and King, C. M.
"Germination Studies of Some Trees and Shrubs,"
Proceedings of the Iowa Academy of Science, 30(1), 287-293.
Available at: https://scholarworks.uni.edu/pias/vol30/iss1/48