Word Quiz of the Week

by Mary Free, Extension Master Gardener

Chelone (turtlehead) and Penstemon (beard-tongue), both members of the Plantaginaceae (plantain family), are described as having five stamens—four fertile and one sterile. What is the sterile stamen called?

Sterile stamens vary in appearance according to the species. In Aquilegia (columbine), they look similar to fertile stamens. In Penstemon (beard-tongue), they look similar to a filament without an anther. In Chelone (turtlehead), they hide at the base of the corolla, while in Canna they are arguably the showiest part of the flower. Click here to learn this term, new to the Illustrated Glossary.

The simple pistils of Aquilegia canadensis (wild columbine) have a superior ovary, exserted style, and stigma. Fused staminodes persist after stamens abcise, falling away as follicles expand. — Persistent fused sterile stamens of *Aquilegia candensis* (wild columbine).
Photo © Mary Free

Four fertile stamens and an apically pubescent staminode of Penstemon digitalis (foxglove beard-tongue) in May. — Four fertile stamens and an apically pubescent sterile stamen of *Penstemon digitalis* (foxglove beard-tongue). Photo © Mary Free

A longitudinal section of Chelone glabra (white turtulehead) showing four pubescent fertile stamens and a much reduced green staminode (far right). Photo © Gilles Ayotte, Kalos, Bibliothèque de l’Université Laval CC BY-SA 4.0 — Four pubescent fertile stamens and a much-reduced green sterile stamen at the base of the *Chelone glabra* (white turtlehead) corolla. Photo © Gilles Ayotte, Kalos, Bibliothèque de l’Université Laval CC BY-SA 4.0