Sorghum halepense - Johnson Grass

Johnson Grass is an erect, perennial, rhizomatous grass, to 3.5 m tall. It is a principal weed of corn, cotton, and sugarcane, and a weed of many crops throughout the world. Leaf-blades 20-90 cm long; 5-40 mm wide. Leaf-blade margins scaberulous. Inflorescence is a panicle with branches tipped by a raceme. Panicle are open lance-shaped or pyramidal, 10-55 cm long, 3-25 cm wide. Primary panicle branches are whorled at most nodes, moderately divided. Racemes are 1.2-2.5 cm long, bearing few fertile spikelets, bearing 1-5 fertile spikelets on each. Rhachis is fragile at the nodes, ciliate on margins. Rhachis internodes filiform. Rhachis internode tip transverse, cupuliform. Spikelets occur in pairs. Fertile spikelets are stalkless, 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; ciliate. Johnson Grass is native to eastern Europe, but now naturalized throughout the world.