Cyperus compressus L.
Common Name : Poorland flatsedge
Family : Cyperaceae

HABIT |
AN ERECT GLABROUS, CAESPITOSE ANNUAL (SOMETIMES BIANNUAL), 5-75
CM HIGH. ITS ROOTS ARE TUFTED, FINE AND NUMEROUS. |
STEMS |
ERECT, TUFTED, SLENDER OR
RIGIDULOUS, GLABROUS, COMPRESSED, TRIGONOUS AND 0.5-2.0 MM THICK. THE BASE IS
COVERED WITH RED-PURPLE, USUALLY ENTIRE AND NON-FIBROUS, LOOSE, OPEN LEAF
SHEATHS. |
LEAVES |
THE LEAVES ARE AS LONG AS OR SHORTER THAN THE STEM. THEY ARE
SUBCORIACEOUS, FLAT, 1.5-4.0 MM, BROAD, GREYISH-GREEN, NARROWLY LINEAR AND
TAPER GRADUALLY TO A FINE ACUMINATE APEX. |
FLOWERS |
THE INFLORESCENCE HAS
UMBELLATE SPIKES, SOME OF THE RAYS (USUALLY 3-4) ARE WELL DEVELOPED AND UP TO
8 CM LONG. THE SPIKELETS ARE STRONGLY COMPRESSED LATERALLY AND THERE ARE 4-7
IN EACH ULTIMATE CONDENSED UMBELLATE SPIKE. THESE ARE 1.5-3.5 CM LONG, 3-5 MM
WIDE AND GREY-GREEN, STREAKED WITH CRIMSON. |
FRUITS |
NUTLETS ARE SHORTLY
STIPITATE, OBOVIOID, BROADLY TRIQUETROUS, 1.5-1.7 MM LONG WITH THREE
PROMINENT ANGLES AND THREE CONCAVE SIDES. THEY ARE DARK BROWN OR
BLACKISH-BROWN, APICULATE AND GLOSSY. |