Itch grass is competitive with annual crops and invades sugarcane, pastures and roadsides. It is difficult to manage once established. Because of its size and vigorous growth, itch grass is competitor for sugarcane and heavy infestations can cause severe crop loss.
While sometimes described as unpalatable to livestock, grazing has shown to the reduce incidence of Itch grass.
A single large plant can produce 2,000 to 16,000 seeds that are shed by the plant as soon as they mature. It is a significant weed in several crops including maize, sugarcane, upland and rain-fed rice, beans, sorghum and perennials such as citrus and oil palm at early stages of growth.
Itch grass has a single stem that is cylindrical, hollow and branches into sheaths at upper nodes. The stem and leaves are covered in stiff hairs that can cause irritation to skin. Itch-grass leaves are blue-green in colour in good conditions but often yellowish, flat, 5-20 mm wide with round edges and a conspicuous pale mid-vein. Flower heads are borne in pairs that branch out from the upper nodes and form green spikes about 10cm long. As the heads mature, the cylindrical rice sized seeds progressively break free from the end and fall to the ground. Itch grass seed is known to germinate after the first significant rain in summer.