Invasive pasture weed spreads in Taranaki

Yellow bristle grass, a highly invasive pasture weed with no effective controls and a major financial impact, is appearing in Taranaki dairy paddocks. It's a pest plant horror story and so far there's little anyone can do about it, other than try intensive pasture renovation over three seasons reports the Taranaki Daily. Farmers in the Waikato, where YBG is now rampant, say it's costing them $1100 a hectare in lost production and it just keeps getting worse. Setaria pumila is a common roadside grass that has jumped the fence and gone berserk. It may also have come in with imported hay, silage, or balage. It's widespread in Northland and the Bay of Plenty. Now Taranaki farmers are seeing it in their pastures. Some finding it on their farms are scared to talk about it because they are worried it will discourage potential sharemilkers. Cows don't like it. There's no selective spray available. The grass is difficult to identify until it produces a seed head and by then it's too late, because the plant will have dropped tens of thousands of highly viable seeds. AgResearch scientists are experimenting with cropping and regrassing trials in the hope of coming up with a management strategy for farmers. The Ministry of Agriculture and Forestry's sustainable farming fund has committed $396,000 to the YBG project. The grass was identified as a serious problem in 2006. It flowers annually and quickly dominates other pasture species. The only consolation for host farmers is that it has a relatively short growing period and doesn't survive frosts. The grass is common on roadsides, where it's also known as foxtail or millet. In some countries, the grass is grown for birdseed. The young plant is palatable to stock, but they avoid it once the soft, bristly seed heads emerge from about mid-January through to May, a critical period of the milking season. That means infected paddocks must be mown for hay or cut for silage before Christmas.