Many people mistake little barley (Hordeum pusillum) for a little foxtail because the foxtail and little barley seedheads are similar. However, little barley is a winter annual that comes up in late 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 seedheads until mid-to late-summer. 

So, why are we talking about little barley now? Because now is not the time to control it unless it is in an area where a non-selective herbicide that kills everything such as glyphosate (Roundup) can be used. The best control for little barley in turf 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 in early September can thicken up a tall fescue lawn and prevent a little barley infestation. However, if you do not plan to overseed even though the lawn is a bit thin, preemergence herbicides can be used to provide at least partial control of this weed. The only preemergence herbicide that I know is labeled specifically for little barley is Weed Impede by Monterey Lawn and Garden. 

Weed Impede can only be used on warm-season grasses (bermudagrass, buffalograss, zoysiagrass) and tall fescue that is grown in warm-season areas such as Kansas. However, Dimension (dithiopyr) a pre-emergent, 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 about mid-September and water in to activate. If overseeding, do not apply any preemergence herbicide as it will interfere with the germination of tall fescue.

Lauren Fick is a Cottonwood Extension District Horticulture Agent. Contact her at the Hays office, 785-628-9430, or the Great Bend office, 620-793-1910.