RUTHERGLEN bugs in lucerne must be controlled immediately, according to Agriculture Department crop protection specialist Terry Piper.
During a Liebe Group, Agriculture Department and WA Lucerne Growers Association field walk in Wubin recently, Mr Piper said rutherglen bug caused significant damage in the first week of infestation and needed to be sprayed out as soon as possible.
The problem was many people found it difficult to identify, especially at the juvenile stage when they were minute.
Insect pests were not the only concern.
Mr Piper said weed competition would not only impair establishment in all perennial pastures, but some were difficult to spray out once the pasture matured, such as roly-poly and Afghan thistle.
Mr Piper advised that all weeds be controlled prior to establishment.
Where lucerne is to be grown, he recommended Afghan thistle be sprayed a year prior to sowing with Tordon, due to its residual nature.
He said roly-poly was difficult to control, but Bromoxynil sprayed early at 1-2L/ha should control it.
If the plants are larger, he said an alternative was mowing, but not many people in the eastern Wheatbelt had the necessary equipment to mow.
Roly-poly in lucerne could be controlled with Sprayseed once the plants established a big root system after about one year.