Barley grass (Critesion spp.) is an annual weed commonly found in high-fertility soils. It is most prevalent in areas where the pasture has been damaged and patches of bare soil become exposed. These conditions are often seen on stock camps, along fence lines, shelter belts, and any other areas damaged through high use.

If left uncontrolled, barley grass can spread year to year as stock will not graze it once it has gone to seed. Animals then overgraze or damage other parts of the paddock, allowing the seed to germinate without interference.

Barley grass itself is not an issue in terms of palatability and nutritional make-up during the late autumn and winter months, but the quality is low through late spring. Once gone to seed, the grass dies off, leaving bare ground awaiting next year’s germination. Presenting low-quality feed during a major growth period, along with potential animal health issues, are reasons why this grass weed needs to be controlled to prevent spreading.

The sharp awns on the seed heads can injure both working and pet dogs with vet clinics often treating numerous animals a day for barley grass seeds during spring. These same problems can also occur in livestock, particularly lambs with their softer pelts. If the seed causes an infection, growth rates can lower alongside the already lowered quality of the stock’s diet.

On small areas, grubbing, rouging, continuously mowing or intensively grazing barley grass can help diminish the population by preventing it from going to seed. As the seed is not capable of surviving in the soil easily, solid progress can be made over a few years.

If larger areas of the paddock present with barley grass, or if it spreads throughout the paddock, use an ethofumesate herbicide for effective control. Apply to the weed at an early growth stage, after the main germination has occurred. Some residual control is provided, so there is no requirement to wait for every plant to germinate. Germination occurs between April and July, after the autumn rains.

Graze the paddock to three to 5 cm in height and then allow the grass to freshen up before applying a herbicide as full coverage is essential. Do not apply a herbicide after July. The active ethofumesate is selective to ryegrass, and does not affect it, but it is not safe on clover.

Barley grass can also be managed by spraying out using a glyphosate product followed by re-sowing new pasture.

Discuss barley grass management in pasture with your local PGG Wrightson Technical Field Representative.