The acute bractlets are three-lobed, halberd-shaped, sparingly cut-toothed on one side.
"Scientific American Supplement, No. 421, January 26, 1884" by Various
Root-leaves large, halberd-shaped, and supported on stems six inches in length.
"The Field and Garden Vegetables of America" by Fearing Burr
Fruit with the scales obliquely halberd-shaped and cut-toothed, 3/4 in.
"Trees of the Northern United States" by Austin C. Apgar