Dallisgrass
Paspalum dilatatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paspaleae
Grass Category
Invasive/Weed Grass, Pasture/Forage Grass
Variety / Cultivar
Common Dallisgrass (Wild Type)
Hardiness Zones
USDA Hardiness Zones 7-11; excellent heat tolerance; goes dormant and turns brown quickly after the first hard frost.
About This Grass
A coarse-textured, light green perennial that grows in a distinct starburst or clump pattern. It grows much faster than surrounding turf (like the Bermuda grass shown in the photo background), creating an uneven shelf. Unmowed, it can reach 2-4 feet; maintained, it forms unsightly, low-lying wide clumps. Seed heads consist of 3-5 drooping racemes with black-speckled seeds.
Blade Characteristics
Coarse blades (5-12mm wide), flat, with a sharp pointed tip. Color is typically a yellowish-green to bright green. Vernation is rolled in the bud. The ligule is tall and membranous; auricles are absent. Long hairs are typically present at the leaf base near the collar.
Root System
Deep, fibrous roots with short, woody rhizomes that store energy; very high thatch tendency within the clump; extremely fast establishment; difficult to eradicate due to carbohydrate storage in rhizomes.
Growing Information
Origin Region
Native to Brazil and Argentina; widely naturalized in the Southern United States and Transition Zone.
Growth Habit
Bunch-type/Clump-forming with short, thick rhizomes; forms thick, spreading circular mats over time.
Sunlight & Water Needs
Full Sun (minimal shade tolerance); high water needs for peak growth but extremely drought-tolerant once established; prefers moist, heavy clay or loamy soils but adapts to many pH levels.
Mowing & Maintenance
Hard to control with mowing as it grows horizontally; ideal height is N/A as it is usually a weed, but it survives 1.0-3.0 inches. Fertilization (Nitrogen) accelerates its dominance over desirable turf. High maintenance for removal; requires specific post-emergent herbicides.
Special Characteristics
Extremely high wear tolerance; highly resistant to most common turf diseases; poor salt tolerance; very difficult to crowd out because it physically smothers desirable grasses like Bermuda or Zoysia.
Ecological Information
Introduced/Invasive in turf settings; originally imported as forage for cattle; provides some seed for songbirds but is primarily considered a noxious weed in managed landscapes; often found alongside Bermuda grass or Crabgrass.