Silent stalker

A new weed pest with destructive potential for native grass cattle pastures is spreading from east to west in Kansas and moving into counties like Chase, Marion and McPherson.

In a strange twist to its story, the weed is coming at a time when American society is changing with new demands for goat meat that may make the results of its invasion partly beneficial for Kansas farmers and ranchers.

The weed is sericea lespedeza, a perennial legume native to eastern Asia. It was introduced in the United States in 1896 by the U.S. Department of Agriculture for forage, hay, seed production, and eventually for erosion control and wildlife.

In an ironic twist, Jeff Davidson, Greenwood County extension agent, noted that USDA still lists sericea as a crop species while Kansas last year became the first state to declare a federally listed crop a noxious weed, calling for its extermination within the state.

Davidson, whose county already has major sericea problems, said when Kansans ask USDA for help in controlling sericea, it confuses the agency having the same plant listed as a crop.

Steve Tonn, Marion County extension agent, said sericea is in spots in the county, mostly in Conservation Reserve Program (CRP) land planted to native grass within the last 20 years.

Most likely the grass seed was contaminated with the sericea, and could have come from anywhere in the country, he said.

Davidson said USDA required purity tests of the grass seed used for CRP, but contamination with crop seeds was allowed, so under USDA guidelines, sericea was of no more of a consequence than sweet clover contamination.

Tonn said producers need to pay attention to persons-like Davidson from further east-who have been fighting sericea to become educated aboiut the weed before it gets out of hand here.

“From a distance, it might look like you have a small evergreen tree growing out there to some degree,” Tonn said.

“It can get three feet tall in small clumps, with darker leaf color and different stem structure. The first thing you know, it’s taking over.”

Davidson said cattle find sericea low in palatability primarily because, just like oak trees and some brushy plants, the sericea is high in tannins-substances that can draw soft animal tissues together in a pucker.

“Cattle do eat it, but they don’t like it, and they don’t graze enough of it to control it,” Tonn said. “We have some of the most productive, palatable grass in the world in Kansas, and that’s actually part of the problem. Down south where the sericea is in less palatable grasses like bermuda and fescue, the cattle might eat more of it.

“It’s still regarded as a hay, forage and erosion control crop in the south. Sercia’s known as ‘poor man’s alfalfa’ in the southeastern states.

“It was introduced in the 1920s and 1930s in southeast Kansas to reclaim mine spoils, and it was good for that.”

Sericea, also called Chinese clover bush, has few disease or insect problems, and tolerates drought, acidity, low fertility and shallow, poor soils, according to Paul Ohlenbushch, range and pasture management specialist at Kansas State University.

Davidson said sericea was thought to be a good wildlife plant, and so was planted at federal water reservoir projects in Kansas into the 1950s. It was planted throughout Missouri as a roadside plant, he said.

“Quail appear to like the seed, and so do deer,” Davidson said. “But it’s a little legume seed without the nutritional level for energy intensity to carry quail through the winter. They can starve to death eating it when it squeezes out the other plants they need. Underlying grass may be gone leaving only bare sericea stems for winter cover. So wildlife enthusiasts, prairie botanists and others are just as concerned as cattle producers about it.”

He noted that animal consumption of the seed may contribute to sericea’s spread because the seed may pass undigested in manure.

Davidson said sericea appears to have adapted more to the American environment over the past 75 years, and is thriving in lower-rainfall areas like western Kansas, where it was recently introduced in CRP plantings. It has a better ability than most plants to slow photosynthesis during drouth, he said.

Sericea competes for moisture and nutrients with other plants, and shades them out with a covering leaf canopy that averages three feet tall, and may grow to four feet, Davidson said.

In Greenwood County he has seen grass production cut to 40 or 50 percent very quickly in some pastures with some reduced as much as 80 percent.

He cited Emporia State University studies which showed native-grass stands that had 27 native forbe species and 12 native grass species before sericea which were reduced to nine forbes and four grasses after sericea.

Davidson said he has seen sericea infestations appear to stop at the border of a pasture at a barbed wire fence only to have a clump appear in the middle of the next pasture followed by serious coverage over the next two years.

“The plant isn’t showy,” he said. “It resembles native plants. It doesn’t look bad.”

What thrives on sericea, and appears to be entering an era of increased market demand, are goats. Ohlenbusch said his studies show goats will graze sericea heavily, and may help limit its spread and seed production.

Davidson said goats are predominantly browse, or brush, eaters that aren’t bothered by tannin, and actually digest it, while in cattle it ties up protein.

In Greenwood County the first people to graze goats with cattle are finding the goats graze the sericea, and leave the grass, he said.

College studies, he said, showed that goats ate 50 percent browse, 30 percent forbes and 20 percent grass while cattle ate 60 percent grass, 20 percent forbes and 20 percent browse, and sheep ate 40 percent grass, 40 percent forbes and 20 percent browse.

The two-species grazing requires adaptability on the part of producers because goat management changes their lifestyle, and practical, expensive items like different fences that can keep goats in may have to be added, he said.

But this may also add to the market potential from the land, Davidson said.

“We have to remember that the rest of the world hasn’t been like the United States, and goat is still the meat most eaten in the world,” he said. “Many countries eat more goat than any other meat. A lot of these people are coming to the United States. Many hispanics and many people of the Muslim religion want goat.”

He said most goats that traditionally have been raised in Kansas are dairy breed goats. Kansas cattlemen are bringing in meat-breed goats, primarily from the south for production. The major two meat breeds are Boer and Kiko with some interest also in Spanish goats that come out of Mexico, he said.

Bill Mathias, owner of the Herington Livestock Auction, confirmed that he is seeing this kind of demand for goats at the sale barn’s monthly sheep and goat auction. Especially male goats are being purchased for truck loads that go to high urban hispanic areas primarily in Pennsylvania.

Mathias said prices range from $30 to $100 a head with the high end going for the larger, fleshier goats. He said the ideal animal is a castrated male that has been grain-fattened.

Davidson said goats are sold at auctions to these types of sources also at Eureka and Yates Center.

He said chemical herbicides to kill sericea can be expensive, and it’s best for producers to use them for spot treatments when sericea first appears rather than wide-acreage broadcasts later.

He said Remedy from Dow Chemical is used for June application and Escort from Dupont is used for late September application just before frost.

The herbicides appear to work slowly, but they work well, he said, stopping seed production on a plant that may produce 1,000 seeds per stem.

Davidson hopes producers from many counties will make it to a sericea field day at 3:30 p.m. May 16 at the Bazaar School House six miles south of Cottonwood Falls to learn to recognize and control the plant.

He said participants will learn equipment and calibrations needed for spot control before the weed has a chance to become an overwhelming expensive problem for them.

He noted that Chase County is in the situation where isolated clumps of sericea are appearing, and it will be a good opportunity to learn to find it.

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