Dallisgrass (Paspalum dilatatum) is a fast-growing perennial weed that invades lawns and gardens with clumps of unsightly and unwanted grass. Dallisgrass thrives in poor soil conditions, spreads rapidly, and is difficult to control once established.
Knowing how to spot the early warning signs of a dallisgrass invasion could save your lawn from complete destruction, so come learn all about identifying and preventing this lawn weed!
Dallisgrass is often mistaken for crabgrass or other coarse grasses, but it has distinct features that make it identifiable. It grows in dense, circular clumps with coarse, light green leaves that are wider than typical turfgrass. Unlike crabgrass, which is an annual weed, dallisgrass is a perennial, meaning it returns year after year. Its deep root system allows it to survive drought and heat, making it a persistent problem in many lawns.
Dallisgrass produces seed heads that stand out from surrounding grass. The seed stalks grow upright, reaching up to 3 feet tall, and have multiple branches with dark-colored, fuzzy seeds arranged in a characteristic pattern. These seed heads are a key identifier and contribute to its rapid spread. It also develops thick stems that grow in a circular pattern, creating unsightly patches that disrupt the uniformity of a lawn.
Key Features Of Dallisgrass
Dallisgrass is more than just an eyesore, as it actively competes with turfgrass for nutrients, water, and sunlight. Because it grows in thick, clumping patches, it disrupts the uniform appearance of a lawn, creating a rough texture that makes mowing and lawn maintenance more difficult. Its rapid growth means it often outpaces surrounding grass, requiring more frequent mowing to keep it under control.
Another major issue with dallisgrass is its ability to withstand harsh conditions. It thrives in compacted soil, tolerates drought better than many turfgrasses, and spreads quickly through both seeds and underground rhizomes. This makes it extremely difficult to eliminate, as even small fragments of its root system can regrow into new plants. Its seed heads produce a sticky sap that can attract insects and pests, further complicating lawn care and leading to secondary causes of destruction to your turf.
Problems Caused By Dallisgrass
Dallisgrass is a warm-season perennial, meaning it grows actively during warmer months and survives winter through underground roots. Its ability to spread by both seeds and rhizomes makes it particularly difficult to control. Knowing how it behaves throughout the year can help homeowners time their prevention and removal efforts more effectively.
As temperatures rise in spring, dallisgrass begins actively growing from its underground rhizomes. New shoots emerge, forming small but noticeable clumps in the lawn. At this stage, seeds from the previous season may also begin to germinate, further expanding the infestation. Early intervention is crucial to prevent its spread.
Dallisgrass grows aggressively in the summer, with clumps expanding and seed heads appearing. The seed stalks grow tall and produce thousands of seeds, which are easily spread by wind, mowing, and foot traffic. Because dallisgrass thrives in heat and drought, it often outcompetes turfgrass in stressed areas of the lawn.
Dallisgrass continues growing in the fall, though its spread slows as temperatures drop. Its seeds remain viable and can settle into the soil for future germination. The underground rhizomes strengthen during this period, preparing for winter survival.
In colder regions, dallisgrass goes dormant in winter, with its above-ground foliage dying back. However, its underground rhizomes remain alive and will regrow in the spring. Without proper removal efforts, it will return stronger each year.
Preventing dallisgrass from taking hold is the best way to avoid the challenge of removing it later. Since it thrives in compacted soil and weak turf, keeping a dense, healthy lawn is the first line of defense. Regular lawn care practices, such as proper mowing, watering, and fertilization, can help prevent dallisgrass from gaining a foothold. Applying a pre-emergent herbicide in late winter or early spring can also stop seeds from sprouting.
Prevention Strategies
Once dallisgrass is established, removal becomes more difficult due to its deep root system and rhizomes. Small infestations can be removed by hand, but care must be taken to extract the entire root system. For larger infestations, post-emergent herbicides are often necessary. Non-selective herbicides like glyphosate can kill dallisgrass but will also harm surrounding turfgrass, so they should be used carefully.
Removal Methods
If you spot dallisgrass or any similar-looking weeds taking over your lawn, it is always best to call a professional lawn care company to safely restore your turf. If you need weed control services around Albany, GA, call Pro Outdoor Landscape Management today!
