🌿 Weed
ANX-WEED-0000251
Purple Nutsedge
Cyperus rotundus
Purple Nutsedge (Cyperus rotundus), a perennial sedge weed of the Cyperaceae family.
- Family
- Cyperaceae
- Growth habit
- Sedge
- Life cycle
- Perennial
- Invasive status
- Invasive, often described as one of the world's worst weeds
- Native region
- Tropical Africa/Asia, now pantropical.
- Reproduction
- Underground tubers and rhizomes - regenerates from tiny tuber fragments, making it extremely difficult to eradicate by tillage alone.
Environment
Habitat & Growing Conditions
- Habitat
- Cultivated fields, lawns, wet or irrigated ground.
- Climate requirements
- Warm temperate to tropical; thrives with irrigation and warm soil.
- Soil types
- Grows in almost any soil, including poorly drained or compacted ground.
Impact
Crops Affected & Economic Impact
- Affected crops
- Vegetables, maize, cotton, sugarcane, rice, and most row crops
- Competition impact
- Releases allelopathic compounds that suppress neighbouring crop growth; tuber network makes stands persistent for years.
- Economic impact
- Ranked among the costliest weeds globally in vegetable and row-crop production due to the difficulty of eradication.
Management
Control Methods
- Control methods
- Deep, repeated cultivation to exhaust tuber reserves, solarization, and long crop rotations with smother crops.
- Organic control
- Repeated removal of shoots to starve underground tubers, black plastic mulch/solarization in hot climates.
- Chemical control
- Systemic herbicides that translocate to tubers (e.g. halosulfuron, glyphosate on actively growing foliage) - contact herbicides alone are ineffective since tubers resprout.