North America Non-native Plant

Compact Brome

Botanical name: Bromus madritensis

USDA symbol: BRMA3

Life cycle: annual

Habit: grass

Native status: Non-native, reproduces and persists in the wild in Hawaii âš˜ Non-native, reproduces and persists in the wild in the lower 48 states  

Synonyms: Anisantha madritensis (L.) Nevski (ANMA12)  âš˜  Anisantha matritensis (L.) Nevski, orth. var. (ANMA27)  âš˜  Bromus matritensis L., orth. var. (BRMA16)  âš˜  Bromus madritensis L. ssp. madritensis (BRMAM3)   

Compact Brome: What Every Gardener Should Know About This Non-Native Grass If you’ve spotted a small, delicate-looking grass with compact seed heads popping up in your garden, you might be looking at compact brome (Bromus madritensis). This annual grass has made itself quite at home across many U.S. states, though ...

Compact Brome: What Every Gardener Should Know About This Non-Native Grass

If you’ve spotted a small, delicate-looking grass with compact seed heads popping up in your garden, you might be looking at compact brome (Bromus madritensis). This annual grass has made itself quite at home across many U.S. states, though it’s not originally from around here. Let’s dive into what makes this little grass tick and whether it deserves a spot in your landscape plans.

The Basics: What Is Compact Brome?

Compact brome is a non-native annual grass that has established itself throughout much of the United States. Originally from the Mediterranean region, this adaptable little plant has proven quite successful at making new homes for itself from coast to coast. As its name suggests, it produces relatively compact, dense seed heads compared to some of its grassier cousins.

Where You’ll Find It

This enterprising grass has spread to quite a few states, including Arizona, California, Hawaii, Illinois, Maryland, Michigan, Mississippi, Nevada, Oregon, and Virginia. It’s one of those plants that reproduces on its own in the wild without any human help and tends to stick around once it arrives.

What Does It Look Like?

Being an annual grass, compact brome completes its entire life cycle in one growing season. It’s not particularly showy or ornamental – you won’t find it winning any beauty contests in the plant world. The grass produces small, compact seed heads that give it its common name, and like most grasses, it’s wind-pollinated rather than relying on bees or other pollinators.

Growing Conditions and Habitat

One thing about compact brome – it’s not picky about where it grows. This grass strongly prefers upland areas and almost never appears in wetlands across most regions. In the Western Mountains, Valleys, and Coast region, it’s a bit more flexible and may occasionally pop up in wetter areas, but it’s still primarily a dry-land species.

Should You Plant Compact Brome?

Here’s where things get interesting. While compact brome isn’t officially listed as invasive or noxious, it’s not exactly a garden star either. This grass doesn’t offer much in terms of:

  • Ornamental value or aesthetic appeal
  • Wildlife benefits or food sources
  • Pollinator support (it’s wind-pollinated)
  • Intentional landscaping purposes

Most gardeners encounter compact brome as a volunteer plant rather than something they’ve deliberately chosen to grow. If you’re looking to add grasses to your landscape, you’ll likely find much better options among native species.

Better Native Alternatives

Instead of compact brome, consider these native grass alternatives that offer more benefits for your local ecosystem:

  • Regional native bunch grasses that provide wildlife habitat
  • Native grasses that support local pollinators and beneficial insects
  • Indigenous species that are naturally adapted to your specific climate
  • Native grasses that offer better ornamental value and garden performance

Managing Compact Brome

If compact brome has already made itself at home in your garden, you can manage it like any other weedy annual grass. Since it completes its life cycle in one year, preventing it from setting seed is key to controlling future populations. Hand-pulling before seed production or mowing can be effective management strategies.

The Bottom Line

While compact brome isn’t necessarily harmful, it’s not adding much value to your garden either. This non-native annual grass is more of a background player that’s adapted well to life in various U.S. climates. If you’re planning your landscape, you’ll probably get more bang for your buck by choosing native grasses that support local wildlife and offer better ornamental qualities. Save your garden space for plants that really earn their keep!

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 work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags 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. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Arid West

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Atlantic and Gulf Coastal Plain

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Eastern Mountains and Piedmont

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Great Plains

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Hawaii

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Northcentral & Northeast

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Western Mountains, Valleys, and Coast

FACU

Facultative Upland - Plants with this status usually occurs in non-wetlands but may occur in wetlands

Compact Brome

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Bromus L. - brome

Species

Bromus madritensis L. - compact brome

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