Sicklepod (Note: This is a broadleaf legume, not a grass)
Senna obtusifolia · Summer Annual, C3 Dicot (Not a monocot grass)
Grass Family
Fabaceae (Legume Family), Subfamily Caesalpinioideae (Not Poaceae)
Grass Category
Invasive/Weed Grass (Technically a broadleaf agricultural weed)
Variety / Cultivar
Native/Wild type
Hardiness Zones
USDA Zones 7-11; dies with the first hard frost but persists via a long-lived seed bank in the soil.
About This Grass
An erect, branched annual herb growing 1-6 feet tall. It features alternate, pinnately compound leaves and small yellow flowers that produce long, slender, curved seed pods (sickle-shaped). It often exhibits nyctinasty (leaflets folding together at night or under stress).
Blade Characteristics
Not applicable (has leaflets). Leaflets are obovate (teardrop-shaped), 2-3 pairs per leaf, with a rounded tip and a distinct gland between the lowest pair of leaflets. Color is dull medium-green.
Root System
Strong, deep, branched taproot. Does not form thatch or rhizomes. Very difficult to pull by hand once established.
Growing Information
Origin Region
Native to the Americas (North, Central, and South); widely naturalized in the Southeastern US and tropical regions worldwide.
Growth Habit
Directly erect, semi-woody herbaceous annual; taprooted, not sod-forming.
Sunlight & Water Needs
Full sun preferred; highly drought tolerant. Thrives in disturbed, sandy, or clay soils with neutral to slightly acidic pH.
Mowing & Maintenance
High maintenance for eradication. In turf, it is managed via post-emergent broadleaf herbicides. Mowing prevents seed production but does not kill the plant as it can regrow from the base.
Special Characteristics
Highly resistant to most common lawn herbicides; toxic to livestock if consumed in large quantities; extremely prolific seed producer.
Ecological Information
Commonly considered a noxious weed in agricultural and turf settings. While it provides some nitrogen fixation, its invasive nature in the Southeastern US makes it a target for removal. It serves as a host for some sulfur butterfly larvae.