Native Plants

Tropical Signalgrass

Urochloa distachya

USDA symbol: URDI5

perennial grass

Hawaii: non-native, naturalized
Lower 48 states: non-native, naturalized
Pacific Basin excluding Hawaii: native
Puerto Rico: non-native, naturalized

If you’ve spotted a persistent grass spreading through your garden or neighborhood, there’s a good chance you might be looking at tropical signalgrass (Urochloa distachya). This unassuming perennial grass has quietly made itself at home across many warm regions of the United States, and while it’s not exactly a showstopper, ...

Tropical Signalgrass: What You Need to Know About This Widespread Grass

If you’ve spotted a persistent grass spreading through your garden or neighborhood, there’s a good chance you might be looking at tropical signalgrass (Urochloa distachya). This unassuming perennial grass has quietly made itself at home across many warm regions of the United States, and while it’s not exactly a showstopper, it’s worth understanding what you’re dealing with.

The Basics: What Is Tropical Signalgrass?

Tropical signalgrass is a perennial graminoid – that’s the fancy way of saying it’s a grass-like plant. Originally from tropical regions of Africa and Asia, this hardy grass has established itself as a naturalized resident in several U.S. states and territories. You might also see it referred to by its scientific name, Urochloa distachya, or its former names Brachiaria subquadripara and Urochloa subquadripara.

Where You’ll Find It

This adaptable grass has spread to various locations across the warmer parts of North America and U.S. territories. Currently, you can find tropical signalgrass growing in Florida, Hawaii, Maryland, as well as in Guam, Palau, and Puerto Rico. It’s considered non-native in most of these areas, having been introduced and now reproducing on its own in the wild.

  • Species observed
  • No observations

The Garden Reality Check

Let’s be honest – tropical signalgrass isn’t going to win any beauty contests. This grass lacks the ornamental appeal that most gardeners seek. It’s more of a utilitarian plant, historically valued for forage rather than aesthetics. If you’re looking to create a stunning landscape, this probably isn’t your star player.

However, if you’re dealing with challenging growing conditions where other plants struggle, tropical signalgrass might already be solving that problem for you. It’s remarkably adaptable to different moisture conditions, from drier upland areas to occasionally wet spots, depending on your region.

Growing Conditions and Care

Should you find yourself with tropical signalgrass (whether by choice or by surprise), here’s what it prefers:

  • Climate: Thrives in USDA hardiness zones 9-11, loving warm, humid conditions
  • Soil: Not particularly picky about soil types
  • Water: Adaptable to various moisture levels, though preferences vary by location
  • Maintenance: Low maintenance once established – sometimes too low maintenance, as it can spread readily

The Pollinator and Wildlife Picture

As a wind-pollinated grass, tropical signalgrass doesn’t offer much in the way of nectar or pollen for bees and butterflies. Its wildlife benefits are limited compared to native alternatives that have co-evolved with local ecosystems.

A Better Path Forward: Native Alternatives

While tropical signalgrass isn’t necessarily harmful, choosing native grasses can provide much greater benefits for your local ecosystem. Native grasses support native insects, birds, and other wildlife while requiring less maintenance once established. Consider these alternatives:

  • Research native bunch grasses specific to your region
  • Look into native sedges for moisture-loving areas
  • Consult local native plant societies for the best options in your area

The Bottom Line

Tropical signalgrass is one of those plants that exists in the middle ground – it’s not a garden villain, but it’s not a hero either. If you already have it, it’s not cause for alarm. But if you’re planning new plantings, you’ll likely find much more rewarding options among native grasses that will support your local ecosystem while providing equal or better performance in your landscape.

Remember, the most successful gardens work with nature rather than against it, and choosing plants that belong in your region is always a step in the right direction.

Urochloa distachya is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Urochloa distachya is also known as:

Brachiaria subquadripara | USDA symbol: BRSU
Urochloa subquadripara | USDA symbol: URSU2

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" — matching plants to their ideal growing conditions, so they'll thrive with less care and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection can be if you don't have the right information. While tags on nursery plants list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. You might be surprised to learn that popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. The table below gives insight into the preferred growing conditions of this plant throughout its geographical distribution.

Region
Preferred Habitat

Atlantic and Gulf Coastal Plain (AL, AR, DC, DE, FL, GA, IL, KY, LA, MD, MS, MO, NC, NJ, OK, PA, SC, TN, TX, VA)

Obligate Upland

Caribbean (PR, VI)

Facultative

Eastern Mountains and Piedmont (AL, AR, DC, DE, GA, IL, IN, KS, KY, MD, MO, NC, NJ, NY, OH, OK, PA, SC, TN, VA, WV)

Facultative Upland

Great Plains (CO, KS, MN, MT, NE, NM, ND, OK, SD, TX, WY)

Facultative

Hawaii ()

Obligate Upland
Wetland Glossary
Obligate Wetland
Facultative Wetland
Facultative
Facultative Upland
Obligate Upland
Almost always occurs in wetlands
Usually occurs in wetlands but may occur in non-wetlands
Can occur in wetlands and non-wetlands
Usually occurs in non-wetlands but may occur in wetlands
Almost never occurs in wetlands

Classification

Group: Monocot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Liliopsida - Monocotyledons
Subclass: Commelinidae
Order: Cyperales
Family: Poaceae Barnhart - Grass family
Genus: Urochloa P. Beauv. - signalgrass

Species: Urochloa distachya (L.) T.Q. Nguyen - tropical signalgrass

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA