City highlights quick growing noxious grass Downy Brome

By MEDICINE HAT NEWS on August 2, 2025.

newsdesk@medicinehatnews.com

This week the City of Medicine Hat is highlighting an invasive plant species called Downy Brome grass, or cheatgrass, which is native to the Mediterranean and southwest Asia, and quickly grows during cool season, out-competing perennial seedlings for moisture.

The annual grass reproduces by seed only and each plant can produce up to 5,000 seeds. The grass stands erect and can be slightly hairy and range from 10 to 70 cm, with one to 20 stems on the blade of grass.

The grass produces small leaves which are 4 to 16 cm long and ligules with jagged edges, and blooms small closed and self-pollinating flowers.

The grass has spread across North America via shipping vessels and becomes very persistent once established and is able to aggressively spread in dry grassland areas, especially if those areas are accompanied by overgrazing.

According to the Alberta Invasive Species Council, effective control measures must eliminate the live plant, present seed formation and control seed germination and emerging seedlings.

The council recommends using a combination of control methods repeated throughout the growing season for the best chance of success.

Moving may prevent seed germination, but it also may disperse seeds depending on the different life stages of the grass.

Hand pulling can be effective, but only for a small area. Tilling a large area at least 10 to 15 cm deep, combined with other control methods can be an effective way to eliminate seeds.

Several herbicides and mixtures are registered for use on Downy Brome that include Glyphosate, Dicamba, Pyroxsulam and 2,4-d.

The city says sowing and fertilizing desirable species that will compete with Downy Brome is an effective method to control the noxious species.

“Seed longevity is only a few years and germination rates are usually high,” reads prevention tips provided by the council.

This summer the city has also highlighted prevention tips for other noxious invasive plant species found in the region including Leafy Spurge, Creeping Bellflower and Baby’s Breath.

For more information on how to prevent the spread of these invasive species check out the city’s website and click the “Neat to Know” tab located on the homepage.

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