lakeside daisy

Tetraneuris herbacea is a perennial herb growing from a branching caudex with one or more erect stems measuring 6 to about 35 centimeters (2.4-14.0 inches) tall. The leaves are located around the base of the plant and have rubbery, glandular blades. The inflorescence is a single flower head borne on a hairy peduncle. The head contains 50-250 yellow disc florets surrounded by 7-27 (occasionally 0) yellow ray florets each ray measuring 1 or 2 centimeters (0.4-0.8) in length. The fruit is an achene tipped with a pappus of scales.

Tetraneuris herbacea is known from just a few natural and introduced populations. In Ontario there are about 20 populations all located at the shores of Lake Huron on the Bruce Peninsula and Manitoulin Island. In Ohio, the plant only occurs naturally in Ottawa County, where it can be found at the Lakeside Daisy State Nature Preserve, a protected area named in its honor. There is an introduced population on Kelleys Island, Ohio, as well. In Illinois, naturally occurring lakeside daisies were last seen in 1981, and today the daisies occurring there are introduced populations in nature preserves. In Michigan there is one population in Mackinac County on the Upper Peninsula, which may or may not be naturally occurring. Tetraneuris herbacea occurs on alvars, a type of limestone pavement with little plant cover. These rocky outcrops have thin, alkaline soils and are quite dry in the dry seasons, making them inhospitable for many other plant species, so the lakeside daisy grows in unshaded full sun. In Michigan the habitat is based on tufa and marl, different types of limestone substrate. Tetraneuris herbacea is threatened by the loss of its habitat. The limestone plain where it grows naturally in Ohio, the largest population within the bounds of the United States, is privately owned by a quarrying company that mines the rock. …