Character:  An erect plant similar to Wild-oats, but slightly smaller in appearance.  This weed has a bulbous nodule at the base of the stem giving rise to its name.

Flower: The panicle and spikelets are very similar to Wild-oats, although the panicle is more compact and narrow.

Significance:  Onion Couch once established can be difficult to eliminate. The bulb at the base contains the bud, which develops into a new plant. Cultivations separate the nodules causing the weed to spread rapidly. These nodules can survive drought conditions.