Crop & Pest Report


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What’s that Grass? (08/16/18)

There is a new player in North Dakota. At least I can’t find reference to it having been here before.

What’s that Grass?

There is a new player in North Dakota. At least I can’t find reference to it having been here before. The name is woolly cupgrass (Eriochloa villosa), also called hairy cupgrass. The plant was identified in wheat fields in Richland and Cass counties as the seed heads reached above the wheat canopy late in the season. Density and distribution in the field suggest the plant has been here for a couple years. The plant is considered by some as invasive because it has the potential to quickly dominate the plant community.

The inflorescence gets purple coloration as the plant and seed mature. A rather unique feature is that two rows of seeds develop along one side of each rachis branch of the inflorescence. The rachis and base of each seed is quite hairy, or woolly, which is noted when seeds are shed. The plant has a hairy ligule, but the most distinguishing feature of the seedling is a prominent crinkle/crimp/tight wave of one leaf margin, especially near the base of the leaf.

The plant can grow in a wide range of soil types and conditions. While a majority of seeds will germinate in the warmer part of spring, woolly cupgrass germination extends well into the summer. This allows establishment after POST herbicides have been applied.

My only experience with this weed was in class and contests when I was in school so we will work with it in the greenhouse this winter to gain better confidence in herbicide options. Not many cereal herbicide labels include this weed, but this could be because it has not been present in typical wheat production areas – until now. Please pay closer attention to fields this fall for presence of this weed and start managing its distribution with harvest scheduling and equipment sanitation.



Kirk Howatt

Weed Control in Cereals and Oilseeds

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