Sawtooth sunflower (Plants of the Peggy Notebaert Nature Museum Grounds, Chicago, Illinois)

Sawtooth sunflower

Helianthus grosseserratus

Summary ⁷

Helianthus grosseserratus, commonly known as sawtooth sunflower or thick-tooth sunflower , is a perennial sunflower in the family Asteraceae, with a large flowering head (inflorescence).

Comments ⁸

Notwithstanding its name, the Sawtooth Sunflower often has leaves that are toothless or only slightly serrated. There is considerable variation in the size of plants across different locations, and the leaves are somewhat variable in their size and shape. This sunflower can be distinguished from other Helianthus spp. (sunflowers) by its smooth reddish stems, which often have a powdery white bloom that can rubbed off (i.e., they are glabrous and glaucous). The lower stems on large older plants can become slightly woody in appearance. The Sawtooth Sunflower is similar in size and appearance to Helianthus giganteus (Giant Sunflower), but this latter species has hairy stems and it is usually found in habitats that are more moist and sandy. Return