Johnsongrass

Sorghum halepense

Johnsongrass (Sorghum halepense), a perennial grass weed of the Poaceae family.

Family: Poaceae
Growth habit: Grass
Life cycle: Perennial
Invasive status: Noxious/regulated weed in many countries
Native region: Mediterranean region, now naturalized on most continents.
Reproduction: Seed and thick underground rhizomes - a single plant can produce an extensive rhizome network in one season.

Environment

Habitat & Growing Conditions

Habitat: Cultivated fields, floodplains, roadsides, ditches.
Climate requirements: Warm temperate to subtropical; thrives in hot summers.
Soil types: Prefers fertile, moist soils but tolerates a wide range of conditions.

Impact

Affected crops: Maize, sorghum (cross-pollinates with and can reduce grain sorghum purity), soybean, cotton
Competition impact: Rhizome mats compete intensely for water and nutrients; young growth and drought-stressed plants can also be toxic to livestock (cyanogenic glycosides).
Economic impact: Listed as one of the world's ten worst weeds by the FAO due to its impact on row-crop yields.

Management

Control methods: Deep tillage to expose rhizomes, crop rotation with competitive smother crops, and preventing seed set.
Organic control: Repeated cultivation through the growing season to exhaust rhizome reserves; mowing before seed heads form.
Chemical control: Systemic herbicides (e.g. glyphosate) for rhizome kill; selective grass herbicides in broadleaf crops. Resistant populations are documented in several countries.

🌿 Weed

ANX-WEED-0000254

Sorghum halepense

Johnsongrass (Sorghum halepense), a perennial grass weed of the Poaceae family.

Family: Poaceae
Growth habit: Grass
Life cycle: Perennial
Invasive status: Noxious/regulated weed in many countries
Native region: Mediterranean region, now naturalized on most continents.
Reproduction: Seed and thick underground rhizomes - a single plant can produce an extensive rhizome network in one season.

Environment

Habitat: Cultivated fields, floodplains, roadsides, ditches.
Climate requirements: Warm temperate to subtropical; thrives in hot summers.
Soil types: Prefers fertile, moist soils but tolerates a wide range of conditions.

Impact

Affected crops: Maize, sorghum (cross-pollinates with and can reduce grain sorghum purity), soybean, cotton
Competition impact: Rhizome mats compete intensely for water and nutrients; young growth and drought-stressed plants can also be toxic to livestock (cyanogenic glycosides).
Economic impact: Listed as one of the world's ten worst weeds by the FAO due to its impact on row-crop yields.

Management

Control methods: Deep tillage to expose rhizomes, crop rotation with competitive smother crops, and preventing seed set.
Organic control: Repeated cultivation through the growing season to exhaust rhizome reserves; mowing before seed heads form.
Chemical control: Systemic herbicides (e.g. glyphosate) for rhizome kill; selective grass herbicides in broadleaf crops. Resistant populations are documented in several countries.