Controlled pollinations were performed on four pinyons (Pinus edulis Engelm.) to compare the results of selfing and outcrossing. Final cone size was the same under both treatments. There was no significant difference in number of seeds per cone. Filled-seed yields averaged 14.4 percent in selfings and 90.5 percent in outcrossings. Relative self-fertility averaged about 15 percent, a level comparable with that of other pine species studied.
Lanner, Ronald M.
"A self-pollination experiment in Pinus edulis,"
Great Basin Naturalist: Vol. 40
, Article 7.
Available at: http://scholarsarchive.byu.edu/gbn/vol40/iss3/7