Ricefield Flatsedge

Cyperus iria

sigh-PEAR-us  (sometimes pronounced SIPE-ah-rus) EAR-ee-ah

Cyperaceae

Native to:  Eurasia.  Widely naturalized

Florida abundance and distribution:  Occasional throughout Florida in moist or wet disturbed sites.

Recognition:  The tiny scales that cover the seeds are cupped and give the spikelet beaded look.

Potentially confusion species:  It takes a magnifier to get a good look, but the spikelets are unique among south Florida sedges.

Other:    An important weed of rice in south and Southeast Asia.  Recent systems for increasing rice production and decreasing costs involve reduced water levels that have the side effect of more problems with weeds.  This species is now combated in Asia by hand weeding, rotary weeding, pre-emergent herbicides and post emergent herbicides.

Contributed by: David Black, Ph.D.