Tips to Get Rid of Bahiagrass

Tips to Get Rid of Bahiagrass

Opportunistic and aggressive, 'bahiagrass' grows vigorously and survives under adverse conditions. While providing some easy tips to get rid of it from your garden, this Gardenerdy article also explains how to identify this grassy weed.
Gardenerdy Staff
Did You Know?
Desirable plants produce hundreds of seeds, but a single weed, which reproduces by prolific seed production, can release anywhere between 10,000 to over 100,000 seeds. Thus, weeds can quickly destroy your garden, if left untreated.

Bahiagrass (Paspalum notatum), also known as highway grass, common bahia, or Pensacola bahia, is a sod-forming, deep-rooted grass. This perennial, warm-season grass is native to Mexico and South America. It was first grown in Florida as a forage grass. It makes a good, low-maintenance turf too. Being a drought-tolerant grass, it is ideal for erosion control along roadsides. However, it is usually viewed as a weed. This grassy weed can prove to be a nuisance if it starts growing among more desirable grasses like centipede, St. Augustine, zoysia, or bermuda. As the seeds of bahiagrass generate and spread quickly, other warm-season grasses often become infested with bahiagrass. It is necessary to check whether bahiagrass is growing in your garden. Knowing the type of weed that is growing in your garden and how the herbicide works is very important in weed control.
How to Identify Bahiagrass
  • It has a light green color and coarse texture.
  • Its two ascending seed heads form a distinct 'Y' shape.
  • Its 'V'-shaped inflorescence consists of two spike-like racemes.
  • These racemes contain numerous tiny, smooth, and shiny spikelets that closely overlap in two rows.
  • Each spikelet is about 2.8-3.5 mm long.
  • The flat and tough leaf blades are 4-10 mm wide and 6-25 cm long.
  • At the base (near the rhyzome), the stems have a purplish hue.
  • The slender stems can be 20-75 cm tall.
  • The seeds are oval, yellowish-green, and glossy. They can be 3 mm in diameter.
  • The seed head grows quickly. It can be easily seen above other turf.
Caution
Pollen of bahiagrass (Paspalum notatum) can trigger an allergy in various geographical areas. If you want to avoid exposure to this grassy weed and herbicides, call a local lawn treatment company to do the task.
How to Eliminate Bahiagrass from Your Garden
Bahiagrass control involves use of simple instruments and easily available chemicals. With the help of a herbicide, growth regulator, lawn mower, shovel, spade, and a hand cultivator, you can get rid of this stubborn weed from your lawn, flowerbeds, and vegetable garden.
1. Mow your yard
Regular mowing can inhibit the growth of bahiagrass. Keeping the desired grass a little bit taller than usual can help inhibit the growth of the weed, as it would be deprived of the sunlight. Moreover, the weed won't be able to form seed heads if its topmost growth keeps getting cut off. Use a mower that comes with an attached bag. Collecting the grass in the bag will help prevent the spread of grass seeds. Do not empty the bag in your yard. Empty it only into a garbage can. But as the weed is resilient, this process would not help to get rid of it completely.

2. Fertilize your lawn at the right time
Fertilizing your turf grass at the wrong time can promote the growth of weeds. Provide fertilizer to cool season turf grass in early spring and late fall, and to warm season grass in the summer when it reaches maximum desirable height.

3. Use of growth regulator
You can apply a growth regulator to the entire lawn or just to the spots where bahiagrass is growing. This would help curb its growth during warm weather. But it may affect the growth of regular grass too.

4. Dig it out
You should dig out the pesky weed and prevent it from spreading and damaging your garden. This way, you can get rid of bahiagrass completely. Soaking the lawn with water will help soften the soil, and pulling out the weed with roots will be easier. To remove bahiagrass growing in flowerbeds or vegetable gardens, use a spade or hand cultivator, and pull out the grass and the rhizomes as much as possible. After digging out the weed from flowerbeds, cover the spots with wet newspapers and a thick layer of mulch over them. This would block sunlight and prevent the weed from returning.

5. Use a suitable herbicide
Another option for killing bahiagrass is using a suitable herbicide. A post-emergent herbicide should eradicate just the weed, not your turf grass. If bahiagrass is growing in another variety of turf grass that you want to grow, you should check the label carefully before buying the herbicide. Also, remember that one application is rarely enough. You may have to apply it twice or thrice. If you are using a herbicide that can kill other ornamental plants, cover those plants with plastic or cardboard sheets before applying it.

6. Atrazine and imazaquin herbicides
Atrazine herbicides can be used on St. Augustine and centipede grass, while imazaquin herbicides can be used on zoysia, centipede, and St. Augustine. Atrazine does not damage woody ornamental plants. It is recommended that atrazine should be applied when air temperatures reach 65-70°F. This can prove to be more effective. Depending upon the severity of the problem, you may apply it for four consecutive days. Imazaquin herbicides can damage fescue grass.

7. MSMA and CAMA
CAMA, MAMA, MSMA are all known as organic arsenicals. MSMA and CAMA (crabgrass killer herbicides) are safe on bermuda grass, fescue, and zoysia grass. They can be used to kill this noxious weed.

8. For professionals only
Metsulfuron (Manor) works great for bahiagrass, but is available only to professionals.

9. Sethoxydim and Imazaquin
Sethoxydim and imazaquin can be used for bahiagrass control in centipede grass lawns.

10. Pre-emergent herbicide
Apply a grassy weed pre-emergent herbicide each spring in March. It creates a thin film over the ground, which covers seedlings and keeps them from germinating. It kills the sprouting weeds too.

11. Fill the bare spots
Bare spots and thin turf promote weed infestation. After you dig out the weed, fill all bare spots with sprigs of the grass that you are growing currently. The weed should not be provided space to grow. After digging out the weed from vegetable garden, you should cover the empty spots with wet newspaper sheets, and then spread organic mulch over the sheets. Through proper mulching, you can deprive the weeds of the sunlight they need to survive.
Properties of Bahiagrass
  • Creeping along the ground, it spreads very quickly, by seeds and rhizomes (a horizontal stem that can be at or just below ground level), and roots wherever possible.
  • It tolerates various soil conditions, including drought and saline conditions.
  • In fact, it is considered as an indicator plant for droughty soil conditions.
  • It tolerates shade too.
  • It has a mat-forming habit.
  • It is known for its persistence, and the ease with which it establishes itself.
  • It rarely gets damaged by diseases or insects.
  • The seeds are dispersed by ruminants as well as by wind.
  • The weed grows quickly during the warmer months of the year.

Bahiagrass grows vigorously, like other lawn grasses, and is a tenacious weed. Moreover, it is tolerant of all types of conditions and even certain herbicides. Killing it without hurting the turf can be somewhat difficult. You may have to apply the herbicide several times to eliminate bahiagrass completely. All gardening activities, for example, mowing, fertilizing, watering, reseeding the lawn, etc., if done properly, help keep weeds in control. You should consult an expert and follow his instructions sincerely. Regular care also lowers the need for chemical controls.