AUBURN UNIVERSITY, Ala. – The Foundations may have wanted buttercups to build them up, but that is not the case when it comes to Alabama forage producers.
This time of year, livestock producers are battling the distinctive yellow-colored weed buttercup. While rarely consumed, this weed is toxic to livestock. Because of this, producers should scout their fields regularly and use proper control methods when needed.
David Russell, an Alabama Extension weed specialist, said there are more than a dozen buttercup species throughout the Southeast.
“The most common species in Alabama, and the ones producers are likely to encounter, are hairy buttercup, littleleaf buttercup, bristly buttercup, low buttercup and hooked buttercup,” Russell said. “Since there are so many species, it’s easy to see why people group them under the general buttercup name.”
While some were introduced to the region, many buttercup species are native to Alabama and are well adapted to the environment. Because of this, their growing patterns are aggressive enough to take advantage of many different growing conditions.
Buttercups begin their emergence in fall when summer forages are no longer productive and before the cool-season growth increases. Russell said because of this time period, producers can find buttercups in all types of fields.
“Most buttercup species do prefer sites with adequate moisture, but that includes almost all of Alabama’s productive lands once we get into the rainy winter months,” he said. “Left untreated, they will appear in almost all field situations, from neglected and overgrazed fields to those most productive forage stands.”
Toxic to Livestock
Soren Rodning, an Alabama Extension veterinarian, said if consumed, buttercup can potentially cause serious problems in animals.
“Cattle, horses, goats, sheep and pigs are all susceptible to buttercup toxicity,” Rodning said. “Toxicity varies and depends on several factors including plant age, growing conditions and the freshness of the foliage. Plants are most dangerous in the early growth through the flowering stage.”
Most livestock will normally avoid ingesting buttercup because of the bitter taste it has. However, when placed in an overgrazed pasture, animals may eat the weed because of the lack of other forages.
“Occasionally, cattle and possibly other livestock will develop a taste for buttercup, consuming and preferring it over other available forages with fatal consequences.” he said. “For this reason, it is safest to keep populations of buttercup under control on grazed pastures and offer plenty of healthy forage.”
The leaves and stems of many buttercup species contain ranunculin. Rodning says this glycoside forms the toxic blistering agent protoanemonin when animals chew or crush the plant.
“This bitter-tasting oil irritates the lining of an animal’s mouth and digestive tract,” Rodning said. “As a result, owners may notice blisters on an animal’s lips, swelling of the face, excessive salivation, mild colic and diarrhea that may contain blood.”
In some cases of consumption, livestock will have a decreased appetite and a slowed heart rate. More severe cases can cause skin twitching, paralysis, convulsions and death.
Russell normally advocates for producers to use an integrated management approach to control. However, research has often proven that nonherbicide options, such as disking, mowing and livestock grazing, are ineffective forms of control.
“Herbicide treatments are a producer’s most effective option for controlling buttercup,” Russell said. “Products like 2,4-D or GrazonNext HL are effective but be aware that they may also cause undesirable injury to legume forages.”
Ideally, producers want to control buttercup when it is small and actively growing, which is during fall and early winter. While that time period has already passed, Russell said producers can still control it now. However, they should plan to scout and control buttercup during the ideal time in the next growing season. Depending on their location in the state, the ideal time for control could be from mid-November to mid-January.
“Field conditions are much more favorable for operating equipment during fall and early winter when compared to early spring when rainfall is more prevalent,” he said. “In the fall, herbicide use rates and input costs can be less than in the spring because producers often need a higher product rate to control mature weeds.”
Rodning said a heavy growth of buttercup in a field can be indicative of low soil fertility. Correcting these issues may help producers in their efforts to control buttercup.
“Maintaining a healthy growth of desirable grasses and legumes can help crowd out buttercup,” Rodning said. “Regular soil testing, liming and fertilizing at the recommended levels combined with good grazing management can help producers maintain this healthy growth.”
Russell provides a deeper analysis of controlling buttercups in the webinar Fields of Yellow – Options for Buttercup Control in Forages. For more information about controlling buttercup or other management topics, visit www.aces.edu or contact your county Extension office.