Aquatic and Wetland Vascular Plants of the Northern Great Plains

2. Isoetaceae, the Quillwort Family

1. Isoetes L.

1. Isoetes melanopoda Gay & Durieu -- Blackfoot quillwort

Perennial herb with a rosette of long, terete leaves arising from a lobed, cormlike base; roots numerous and branched, arising from the groove between lobes of the corm. Leaves long, slender and terete, 10-50 cm long, 0.5-3.5 mm wide, mostly hollow with 4 longitudinal air chambers surrounding the central vascular bundle, broadened at the base where the sporangia are contained; the outer leaves producing megasporangia, the inner leaves microsporangia; sporangia oblong, 5-30 mm long, usually brown-spotted, the megasporangia containing many rather large (0.25-0.45 mm in diameter) megaspores, the microsporangia containing numerous, tiny microspores. Jun--Aug. Submerged or in wet soil of swales and temporary ponds; rare, with one old record from Mellette Co., SD, otherwise scattered from MN to s NE; (NJ to MN and SD, s to GA and TX).


Isoetes melanopoda.The swollen bases of the quill-like leaves contain the sporangia.

Return to Family -- Isoetaceae - The Quillwort Family