Tripsacum dactyloides (L.) L.
eastern gamagrass
Family: Poaceae

inflorescence--often 2 or 3 rames at the tip as in big bluestem and others. base of 3 "rames" in the inflorescence spikelets are embedded in the rachis and essentially covered with a very tough glume

This species was recently found growing in a prairie planting in Waushara County. It was probably introduced as a contaminant in the seeds of planted prairie species. This illustrates yet another danger of buying seed from outside the local area. It remains to be seen if this species will persist in Wisconsin.

The plants are tall, the Flora of North America, vol 25 (2003) reports heights of up to 2 meters (4) with broad leaves 9 - 35 mm wide. The arrangement of the flowers on 2-3 or more long branches (rames) 12-23 cm long is reminiscent of big bluestem or even of corn. Male and female flowers are separate, but both are borne on the same branch of the inflorescence. In the middle photo above, the upper purple flowers are male and the lower yellow-green flowers are female. Female flowers with stigmas exserted are shown in the photo at far right.

Tripsacum dactyloides is a native species farther south and is common and even invasive in some places. The Flora of North America shows a range throughout the southeastern U.S.A., west to Texas and extreme southeastern Nebraska and north to southern Iowa and Illinois, Kentucky, West Virginia and Pennsylvania.


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