barnyardgrass

Barnyardgrass, Echinochloa crus-galli, is a common annual grass weed in agricultural fields and disturbed habitats. It is particularly problematic in rice production but also infests maize, soybeans, sugarcane, and lawns. With a broad geographic distribution in warm temperate and tropical regions, it can rapidly colonize flooded and moist ground where crops are grown.

Morphology: The plant is an upright annual grass reaching about 0.3 to 1.5 meters in height. Leaves are long and tapered with a membranous ligule. The inflorescence is a dense, branching panicle bearing numerous small seeds that can be dispersed by wind, water, or machinery.

Ecology: Barnyardgrass germinates over a wide range of temperatures and thrives in wet or periodically flooded soils. It forms a long-lasting soil seed bank and can emerge throughout the early growing season, making timely control challenging.

Impact and management: It competes strongly with crops for light, water, and nutrients, leading to yield losses. Effective management is usually integrated, combining crop competition, timely soil and water management, and herbicides with different modes of action. In rice systems, adjusting flooding, drainage, and crop residue can suppress seedlings. Some populations have developed resistance to herbicides such as ACCase and ALS inhibitors, underscoring the importance of resistance management and herbicide rotation.

Taxonomy and nomenclature: Echinochloa crus-galli is the current scientific name; common names include barnyardgrass and barnyard grass. The species belongs to the Poaceae family, with wide agricultural relevance.