Dallisgrass
Paspalum dilatatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paspaleae
Grass Category
Invasive Weed / Pasture Grass / Forage Grass
Variety / Cultivar
Common Dallisgrass (Wild-type)
Hardiness Zones
USDA Zones 7-11; very heat tolerant; goes dormant and turns brown quickly after the first frost; recovers early in spring.
About This Grass
A coarse-textured, deep-rooted grass that forms unsightly, matted clumps. It is known for its tall, leaning seed stalks that produce finger-like spikes with black-spotted seeds.
Blade Characteristics
Coarse blades (5-12mm wide), flat, with a prominent midrib and pointed tips; color is typically grayish-green; vernation is rolled; has a tall, membranous ligule and no auricles but may have long hairs at the leaf base.
Root System
Strong, deep fibrous root system with short, knotty rhizomes; very difficult to pull manually once established; low thatch tendency in turf but creates uneven hummocks.
Growing Information
Origin Region
Native to South America (Brazil, Uruguay, Argentina); common in the Southeast United States and California
Growth Habit
Bunch-type (clump-forming) but spreads via short, thick rhizomes; grows in large, ever-expanding circular clumps
Sunlight & Water Needs
Full sun (highly sun-loving); high water needs for peak growth but extremely drought-tolerant once established; prefers moist, heavy clay or loamy soils.
Mowing & Maintenance
Maintenance is difficult as it grows faster than turfgrass; requires frequent mowing to 1.5-3 inches to control stalks; requires high-strength herbicides (POST-emergent) for removal.
Special Characteristics
Highly invasive in lawns; excellent wear tolerance (resistant to foot traffic); seeds are susceptible to ergot fungus which is toxic to livestock; high salt tolerance.
Ecological Information
Introduced in the US as a forage grass; provides seeds for some birds but acts as a disruptive invasive in managed landscapes and native meadows; extremely difficult to eradicate from native ecosystems.