lake quillwort
Merlin's grass
isoetes lacustris latin

Isoetes lacustris (lake quillwort or Merlin's grass) is a boreal quillwort native on both sides of the northern Atlantic Ocean.

Introduced to botany by his father, Johannes discovered a rare aquatic plant, the lake quillwort (Brachsenkraut in German; Isoetes lacustris) in a herbarium, which he built with his father at the age of ten.

Isoetes lacustris (lake quillwort or Merlin's grass) is a boreal quillwort native on both sides of the northern Atlantic Ocean.

Several species of Isoetes are commonly called Merlin's grass, especially I. lacustris, but also the endagered species I. tegetiformans and I. virginica.

Isoetes tegetiformans, commonly known as mat-forming quillwort or mat-forming Merlin's grass, is an aquatic pteridophyte endemic to the U.S. State of Georgia.