Wild garlic an increasing problem in wheat fields, specialist says

Wild garlic in wheat appears to be an increasing problem, said a University of Missouri Extension agronomy specialist.

"Last year, a number of fields never got planted to wheat due to the dry fall," said Pat Miller. "This spring I noticed that some of those had a thick stand of wild garlic. So some fields may need to be treated, and I think it is something we need to keep an eye on the next few years." Wild garlic in wheat is a problem mainly because of the possibility of dockage, Miller said. "A check with a couple of elevators showed that dockage can be one-half cent per bushel for the first bulblet found and one cent for each bulblet after that." If there are very many bulblets, the wheat will likely be rejected, he said. If the wheat is going to a flour mill, it will be rejected if there is any garlic.

Wild garlic is similar in appearance to Star-of-Bethlehem and wild onion. Star-of-Bethlehem has flat leaves, a white mid-rib and no "onion" smell. Wild onion has round leaves that are "filled" and more solid, while wild garlic has round, hollow leaves. Wild onion rarely occurs in agricultural production fields.

"Although many often refer to a field of wild onions, in fact it is almost always wild garlic," Miller said.

Wild garlic reproduces by underground bulbs and through aerial bulblets. Tillage may prevent the production of aerial bulblets but can help distribute the underground bulbs throughout the field. Many of the bulbs will sprout in the fall, but some bulbs may remain dormant for up to six years. That can make control a long-term process.

Chemical control can take place in the wheat crop or in a burn-down herbicide application. Always check the label for current rates and restrictions. 2,4-D can be applied to wheat after full tillering but before jointing. "This won't kill the wild garlic but will suppress bulblet production," he said. "However, it may also cause some wheat injury." Harmony Extra is labeled for wheat from the two-leaf stage up to before the flag leaf is visible. Because the herbicide is mainly taken up by the foliage, adequate spray volume and use of surfactant is important. Garlic should be actively growing at the time of the application, and even then results are slow. Check the planting restrictions for harvest and following crops.

Harmony GT received a supplemental label for burn-down applications prior to planting corn or soybeans. It can be tank-mixed with other appropriate herbicides such as glyphosate. When tank-mixed with products such as this, it will assist in the control of weeds that are tougher to kill such as wild garlic, dock and others. Basis is another herbicide possibility. With these products, be sure to check the crop-planting restrictions.

It is difficult to see the wild garlic in a stand of wheat. Infestations tend to be spotty and not uniform in a field.

"When we have fields fallow in the winter we can get a better idea of how much is out there," Miller said. "We can't afford expensive dockage or crop rejection, so consider controlling it now."