Itchgrass

Annuals. Inflorescence a single raceme, either terminal or aggregated into a spatheate false panicle. Racemes fragile, cylindric or slightly flattened; internodes clavate with sunken spikelets, wholly or partly fused to the adjacent pedicel. Sessile spikelet: callus truncate; lower glume broadly convex on the back, smooth; lower floret male with hyaline lemma and palea; upper lemma entire and awnless. Pedicellate spikelet present, a little smaller than the sessile; pedicel oblong, flattened, scarcely distinguishable from the internode.

Rottboellia (commonly called itch grass) is a genus of African, Asian, and Australian plants in the grass family.

The genus was named in honour of Danish botanist Christen Friis Rottbøll (1727-1797).

Species Rottboellia cochinchinensis (Lour.) Clayton - Africa, Asia, Australia Rottboellia coelorachis G.Forst. - New Caledonia, Vanuatu Rottboellia goalparensis Bor - Assam Rottboellia laevispica Keng - Anhui, Jiangsu Rottboellia paradoxa de Koning & Sosef - Philippines Rottboellia purpurascens Robyns - tropical Africa Formerly included

Numerous species now considered better suited to other genera: Chasmopodium, Coelorachis, Elionurus, Eremochloa, Glyphochloa, Hainardia, Hemarthria, Henrardia, Heteropholis, Ischaemum, Lasiurus, Lolium, Loxodera, Manisuris, Mnesithea, Muhlenbergia, Ophiuros, Oropetium, Parapholis, Phacelurus, Pholiurus, Psilurus, Ratzeburgia, Rhytachne, Schizachyrium, Spartina, Stenotaphrum, Thaumastochloa, Urelytrum and Xerochloa.