SafePlants

Windmill Grass: A Detailed Look

Windmill grass, a common name for plants in the genus Chloris, belongs to the grass family (Poaceae). Its distinctive appearance, resembling a windmill, makes it easily recognizable.

Several species are referred to as windmill grass, including Chloris truncata and Chloris verticillata, each with unique characteristics and distributions.

Considerations for Pets

• Some species of Chloris, such as Chloris truncata, are prolific growers and can be considered weeds. This could pose a risk of accidental ingestion by pets if they graze on plants in the garden.

Taxonomy and Nomenclature

• Scientific Name: Chloris (genus)
• Common Names: Windmill grass, Finger grass, Umbrella Grass, Star Grass, Blow-away Grass, Star Or Windmill Grass, Windmill-grass.
• Family: Poaceae (Grass family)
• Chloris truncata is also known as creeping windmill grass.

Distribution and Habitat

• The genus Chloris is found worldwide.
• Chloris truncata is native to Australia and is common in the Western Australian wheatbelt.
• Chloris verticillata is found throughout Nebraska, particularly in the eastern and southern regions, and has been documented in Ohio.

Ecological Role

• Some species, like Chloris truncata, are considered weeds and can be problematic in agricultural settings, particularly in no-till farming systems in central and southern New South Wales (NSW), Australia.

Morphological Characteristics and Growth Habits

• Windmill grass is named for its seed head or inflorescence, which has a windmill-like appearance with 6-20 spicate branches.
• Chloris truncata can be either annual or a short-term perennial, forming a rounded tussock usually less than 50 cm tall.
• Chloris verticillata is a warm-season bunchgrass.
• Leaves can be bluish-green, rough, flat, hairless or with scattered hairs, up to 20 cm long and 6 mm wide.
• Stems can be flattened.
• Some species, like Chloris virgata, have feathery spikelets.

Interactions with Other Organisms

• Chloris truncata is a common summer weed species in the Western Australian wheatbelt.
• Some populations of tall windmill grass (Chloris elata) in Brazil have developed resistance to glyphosate.

Quirky Facts

• The number of spikes in the seed head of some species range from 10-16 and are arranged into at least 2 levels of windmills.

Further Information

• RHS (Royal Horticultural Society) provides information on Chloris truncata.
• USDA-NRCS PLANTS Database.
• Encyclopedia of Life has resources about Chloris cucullata.