Fall herbicide applications on actively growing leafy spurge can help control the destructive grassland weed, says Bruce Anderson, University of Nebraska Extension forage specialist.

Leafy spurge is an aggressive, noxious weed in many grasslands, he says. Cattle won’t eat it, which is fortunate because the plant contains a toxin that causes scours, weakness and even death. In some places, it has overrun entire sections of land, making them virtually worthless.

Controlling leafy spurge on large areas can be costly and difficult, says Anderson. Thus, it’s smarter to treat small patches, especially in CRP fields, before they spread.

On many grasslands, a fall application of Plateau is the best treatment. Apply 8-12 oz/acre of the relatively new herbicide about two weeks before a killing freeze. It’s quite effective and doesn’t injure most native grasses or wildflowers. Another option that may be better for cool-season pastures but will kill most wildflowers is 2-4 pints/acre of Tordon 22K. It’s more expensive than Plateau but doesn’t injure cool-season grasses as much.

Don’t expect to eliminate leafy spurge in just one or two years. Spray again each spring when the tops of escaped plants start turning bright yellow. Two quarts per acre of Grazon or 2,4-D usually is satisfactory. Also, new seedlings often appear after a year or two. So re-examine your grasslands each spring and, if new seedlings appear, control them while they’re small and easy to kill.

“Leafy spurge is a terrible pest if you have it,” says Anderson. “But timely spraying can help you reclaim your grasslands.”