University of Maryland Extension

Roughstalk bluegrass

(More Lawn Weeds)

Roughstalk bluegrass
Poa trivialis

Roughstalk bluegrass
(Photo credit: Perdue University Turfgrass Program: Turf tips 5/2008)

Lighter colored Poa trivialis in a darker tall fescue lawn

Life Cycle

Perennial, cool season grassy weed. 

Growth habit 

Forms light green patches that are evident early in the season. They can turn brown and go dormant in the heat of the summer. Grass blades can look shiny.

Reproduction

By seed and stolon(above ground runners) formation. Prolific seeder. 

Conditions that favor growth

Thrives in poorly drained, compacted soil, shade. Will move into sunny areas of the lawn. Spreads aggressively. 

Roughstalk bluegrass
Roughstalk bluegrass coming out of dormancy and beginning
to grow in early spring

Management In Lawns

  • Cultural practices
    Maintain healthy, dense turf that can compete and prevent weed establishment.

  • Mechanical management
     Small infestations can be dug out; must remove all parts of root. Rent a sod cutter to remove large patches. Then reseed. 
  • Chemical Treatment in Lawns

    Perennial grasses growing out of place in lawns are extremely difficult to control selectively in turfgrasses. Cannot be effectively controlled by any of the herbicides currently on the market. Total lawn renovation or killing the patches using glyphosate (an ingredient in a non-selective herbicide) and then reseeding will slow it down but because of the vast seed bank in the soil it will return.

    Resource

    NC State Poa trivialis (good for identification)

Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2020. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.