20171112 Tulip Tree (Liriodendron tulipifera) - USDA, Illustration
%20-%20USDA%2C%20Illustration.JPG "20171112 Tulip Tree (Liriodendron tulipifera) - USDA, Illustration.JPG")
USDA-NRCS PLANTS Database / Britton and A. Brown. 1913. Illustrated flora of
the northern states and Canada. Vol. 3
USDA, NRCS. 2024. The PLANTS Database (http://plants.usda.gov). National Plant Data Team, Greensboro, NC 27401-4901 USA.