Buffalo grass (Bouteloua dactyloides) is a perennial, warm-season grass native to the North American Great Plains, known for its soft, gray-green to blue-green foliage. It is a popular, low-maintenance turf choice due to its drought tolerance and ability to thrive in poor soils. Understanding the dual mechanisms by which this sod-forming species spreads is important for successful lawn management, as its growth habit influences how quickly it establishes.
Spreading by Stolons (Vegetative Expansion)
The primary method of horizontal spread for buffalo grass is through specialized above-ground stems called stolons. These runners grow outward from the main grass crown, creeping along the soil surface. This vegetative expansion creates genetic clones of the parent plant.
These stolons are segmented and feature nodes, which are points along the stem where new growth can originate. When a node makes firm contact with moist soil, it develops adventitious roots downward and a new shoot upward, effectively establishing a new individual plant. This continuous rooting and shooting process allows a single plant to rapidly colonize an area, forming a thick, weed-suppressing sod over time.
Under optimal conditions, including adequate moisture and warmth, buffalo grass can spread horizontally at an average rate of 30 to 60 centimeters (12 to 24 inches) per year. This lateral growth allows the grass to quickly fill in bare spots and create a uniform turf. Successful establishment is enhanced by conditions that promote strong root development during the active growing season.
Spreading by Seed (Sexual Reproduction)
Buffalo grass also utilizes sexual reproduction through seeds to introduce genetic diversity. The grass is typically dioecious, meaning individual plants are either male or female, with the respective flowers borne on separate plants. Male plants produce light, pollen-bearing flowers on slender stalks that stand taller than the leaves, which facilitates wind pollination.
Female plants produce seed-bearing flowers known as spikelets, which are clustered into hard, burr-like fruits that remain partially hidden among the leaves near the soil surface. These burrs contain one or more seeds and are often difficult to harvest commercially due to their low-growing nature. The seed burrs naturally contain an oil that can inhibit germination, a survival mechanism that helps ensure seeds only sprout when conditions are ideal.
The seeds are naturally dispersed through animal consumption, adherence to fur, or movement by wind and water. Successful germination requires a soil temperature of at least 15 degrees Celsius (60 degrees Fahrenheit) and cold-moist stratification to overcome natural inhibitors. While seeds introduce genetic variability, the resulting plants must rely on stolons to form a dense lawn.
Managing and Controlling Buffalo Grass Spread
Managing buffalo grass involves leveraging its stoloniferous and seeding habits to either encourage or restrict growth. To encourage rapid coverage, focus on stimulating stolon development, particularly during establishment. Applying a starter fertilizer high in phosphorus and nitrogen in early summer, when stolon growth is active, enhances the development of new rooted crowns. Consistent, deep watering during the active growing season also promotes deeper rooting and faster spread.
Controlling spread often requires physical barriers due to the stolons’ aggressive nature. Installing solid lawn edging or a root barrier around garden beds or sidewalks is effective for halting horizontal growth. To suppress seed production, the male flower stalks can be regularly mowed off. Removing the taller male pollen heads prevents fertilization and subsequent seed formation, as the low-growing female seed heads are typically unaffected by mowing.