It’s not really barley but it is little. This small grassy weed seems to be on everyone’s hit list in 2018. For a while it was my number one question I received in the extension office. While many people had it in their lawns this summer it was too early to get any control then. Now is the time!
Little barley (Hordeum pusillum) is a winter annual that comes up in September - October and spends the winter as a small plant. It thrives in the cooler spring temperatures, forms seed heads and dies out usually by July. Foxtail, on the other hand, is a summer annual that does well in hot weather. Also, foxtail will not produce seed heads until mid- to late-summer.
Now is the time to control it for next year. The best control for little barley is a thick lawn that is mowed high enough that sunlight does not hit the soil. Little barley seed will not germinate in such conditions. Overseeding now can thicken up a tall fescue lawn and prevent a little barley infestation. However, if you do not plan to over seed, preemergence herbicides can be used to provide at least partial control of this weed.
The only preemergence herbicide that is labeled specifically for little barley is Surflan. It is also sold under the name of Weed Impede by Monterey Lawn and Garden. Surflan can only be used on warm-season grasses (bermudagrass, buffalo grass, zoysiagrass) and tall fescue grown in warm-season areas such as Kansas. However, Dimension (dithiopyr), is labeled for barley (Herodium spp.) which would include little barley and therefore can be used to keep this weed under control. Because little barley is a winter annual, apply the preemergence herbicide now, in September, and water in to activate. If overseeding, do not apply any preemergence herbicide as it will interfere with the germination of tall fescue.
— Scott Eckert is a Kansas State Research and Extension Agent for Harvey County. Horticulture is his specialty. The Harvey County Extension Office can be contacted at 284-6930.