Strongly rhizomatous introduced perennial with stout stem up to 7 feet tall growing in dense clumps or colonies. Large, wide, drooping leaves up to 36 inches long and 1/2 – 1 1/2 inches wide have a prominent whitish midrib (D). The flower cluster is a large, open panicle from 6-20 inches long usually with whorled branches and spikelets that are often tinged with red or purple (A). Spikelets are distributed over most of the length of the panicle branches (B).
Moist soils in waste areas, ditches and field margins. Johnson Grass is rare at Fontenelle Forest on Hidden Lake Trail. It has not been identified at Neale Woods. Flowering occurs from June to October.
This plant was introduced from the Mediterranean region around 1830 for use as a forage plant. It has moderate forage value, but contains hydrocyanic acid and may be poisonous to livestock if consumed when growth is interrupted by frost or drought. It is a serious weed in many places to our south, but it is not very tolerant of cold which inhibits its northward extension.
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