Farmers and landowners are being reminded it is peak season for the spread of the damaging pest plant yellow bristle grass.

Pest plants officer Darion Embling says grass takes over paddocks and damages the profitability of dairying, so avoiding its spread will help support productivity.

Yellow bristle grass. Photo: WRC

Yellow bristle grass is a summer-growing plant with distinctive, cylindrical seed heads with many yellow-tinged bristles.

Darion says a key way of helping prevent its spread is for farmers to avoid grazing stock or making hay from vegetation growing on roadside verges.

'Seeds can particularly be spread along roadsides by mowers and other mechanical means, as well as in freshly chopped maize silage being moved around. After becoming established on the roadside it can quickly move into farm land,” Darion explains.

'Yellow bristle grass seeds also pass through animals after being eaten and is spread around farm in dung.”

Studies show dairy farms infested by the plant can see a 13 per cent drop in dry matter production, with the cost of supplementary feed required to maintain milk production estimated to be $343 per hectare a year.

Besides not grazing or making hay from roadside vegetation from December to May, here are some other tips to help stop the spread of yellow bristle grass:

• Ensure all imported maize chopped for silage gets into the pit and loose debris is not spread along the access way and into adjacent pasture
• Inspect all incoming hay and machinery unless the source is known to be free of yellow bristle grass
• Restrict feed out of infested hay to areas where yellow bristle grass can be readily controlled
• Check stock being brought in from outside the farm during summer have not grazed yellow bristle grass infested pasture.

For more information or advice visit: www.dairynz.co.nz/feed/pasture/pests/yellow-bristle-grass/ or contact Darion Embling at [email protected] or 0800-800-401.