Four pot trials undertaken by SRA Weed Science Leader, Emilie Fillols, have identified effective pre-emergent control strategies for managing itch grass.

Itch grass (Rottboellia cochinchinensis) is a weed that can be found in cane fields from Central Queensland to the Far North, particularly in the Burdekin and Cairns regions. Infestations can cause severe crop losses. Each plant can produce more than 2,000 seeds with seed able to survival in the soil for seven years. Its stiff sharp hairs on the stem and leaf sheath can irritate and penetrate the skin. It grows to four metres high.

Itch grass has been identified as one of the 12 worst weeds of sugarcane in the Global Invasive Species Database (2020). Due to its large size, it competes with crops for light, water and nutrients.

Emilie Fillols’ replicated trials were conducted in a greenhouse at SRA’s Meringa Station from March 2024 (seed collection) to June 2025.

Pre-emergent herbicides and herbicide mixtures that were highly effective in preventing itch grass establishment have been summarised for growers on page 10 of the latest Cane Matters magazine.

NB. Always refer to the product label and follow conditions of use to prevent crop damage. Diuron, mixed with hexazinone, is the only pre-emergent herbicide in sugarcane that includes itch grass on the label.

(Above): SRA Weed Management Technician, Craig Gower, and Masters student, Victoire Colon, work together on the pre-emergent herbicide trials on itch grass.