It can be a bit of a pain in the backside when you find invasive grasses growing on your lawn, especially when they resemble regular grass. The problem is, that these invasive grasses are so easy to misidentify, and if you don’t take action quickly enough, there can be a lot of damage caused to your lawn. Here, we will take a look at the different types of invasive grasses and what you can do about them.
Table of Contents
Types of invasive grasses
There are many different types of invasive grasses that homeowners can find growing out of their lawns. So I thought I’d make a list of some of the most common types below so that you can quickly have a glance at them and then go into more detail in the proceeding paragraphs. The most common types of invasive grasses are:
- Annual Bluegrass
- Alexandergrass
- Crabgrass
- Green Foxtail
- Nutsedge
- Quackgrass
- Smooth Bromegrass
- Slender Rush
- Tall Fescue
What are Invasive Grasses?
Invasive grasses are simply weeds that have a competitive advantage over the rest of the plants on your lawn. This means that they grow faster, taller and thicker than the rest of the grasses on your lawn, which can quickly lead to them crowding out and choking off the growth of other grasses.
While some invasive grasses may not be too much of a problem and can actually add some variety to your lawn, others can cause extensive damage. For example, quackgrass is an invasive grass that has been known to grow through concrete! Invasive weeds can crowd out your desirable grasses, leading to bald patches on your lawn and allowing them to further spread.
Annual Bluegrass
Annual bluegrass (Poa) is a small, tufted grass that is commonly found in lawns. It has a light-green to blue-green color and forms a dense mat. This weed can be problematic as it germinates quickly, meaning it can outcompete your desirable grasses for space, nutrients and water.
It also produces numerous seeds, which can quickly lead to a large infestation if left unchecked. The grass usually dies during the hotter months or when there’s a lack of rain. On one hand, this is good because the weeds will die as well. However, it can be a bad thing due to the fact that bald spots will appear as it dies off.
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How to get rid of annual bluegrass
- The most effective way to get rid of annual bluegrass is by crowding it out with a thick lawn of your own
- You can also kill it by letting your lawn dry out so try not to water it as often as you have been
- When your lawn starts to dry out, you can simply dig it out using a shovel
- If you find there are bald patches after digging it out, just put down some new grass seed
Alexandergrass
Alexandergrass which is also known as tropical signalgrass or creeping signalgrass is a perennial weed that has flat, hairless leaves. The weed is native to tropical and subtropical regions but can be found in temperate areas as well. It grows in a wide range of habitats, including lawns, gardens, pastures, and agricultural fields.
This species of plant has a very strong growth rate, and if not managed properly, it will quickly overrun the lawn. The plant is also very drought-tolerant, meaning it can survive periods of dry weather when other grasses would struggle.
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How to get rid of alexandergrass
- There are no herbicides that are effective at killing alexandergrass so your best option is to use baking soda
- Once you have applied the baking soda, you will need to dig it up using a shovel
- Alexandergrass is easily mistaken for normal grass so you need to keep an eye on your lawn so it is not messed up
Crabgrass
Crabgrass, also known as “finger grass” is an annual invasive grass that looks very similar to Bermuda grass. It can grow in many places but you’ll typically find it growing on lawns and can spread at a very fast rate. It usually starts sprouting in small areas of a lawn but will quickly branch out in circular areas over a period of time.
Crabgrass has a rougher, more coarse texture than most grasses. This may assist you in distinguishing it from the rest of your lawn. Crabgrass is a problem because it can rob your other grasses of vital nutrients, water and sunlight. This can lead to bald patches and an overall unhealthy lawn.
Crabgrass is an invasive grass that can rapidly spread and cause permanent damage to other plants if left unchecked.
How to get rid of crabgrass
- Use a pre-emergent herbicide to stop it from germinating
- Use a crabgrass mower to pull out the individual crabgrasses.
- Use a direct contact herbicide if the above options are not effective
Green Foxtail
Green foxtail (Setaria viridis) is an annual grass that germinates in the spring. It’s a very fast-growing weed that can rapidly spread and takes over areas of lawns, gardens, pastures, prairies and meadows. The plant gets its name from its long, green leaves that have a fox tail-like appearance.
This weed is commonly confused with other grasses but can be distinguished by its seed head, which is made up of numerous small spikelets. Green foxtail can grow to be quite tall, sometimes reaching heights of 2.5 feet or more.
The plant produces a large number of seeds, which are dispersed by the wind. This means that it can quickly spread to other areas and become a problem.
How to get rid of green foxtail
- Grow a thick lawn from the start. The lawn will start to crowd the patches of foxtail and starve it of vital nutrients
- Apply a selective herbicide directly to the unwanted grass to kill it off
Nutsedge
Nutsedge (Cyperus rotundus) is a perennial invasive grass that can be found in many parts of the world. It’s a fast-growing weed that spreads quickly and can easily take over lawns and gardens.
The key distinction between nutsedge and crabgrass is that nutsedge is perennial, which means it’ll last for two growing seasons if not removed.
This disruptive grass propagates through both subterranean rhizomes/tubers and seeds carried by the wind. This is why it can quickly spread to lawns from closeby farms.
How to get rid of nutsedge
- Never try to pull out nutsedge in the early phases of its growing cycle. If you do, the tubers will break, spreading the roots or causing them to grow back stronger
- By growing a luscious, thick lawn from the beginning, you will be able to prevent any chances of nutsedge weeds being able to spread. The dense grass will crowd out the invasive species and leave no room for germination.
- Another way to get rid of nutsedge is by using a selective herbicide.
Quackgrass
Quackgrass (Elymus repens) is a very common type of invasive grass that can be found throughout North America. It’s a perennial grass that spreads through both its seeds and rhizomes (creeping roots). This makes it very difficult to get rid of once it’s established in an area.
The plant gets its name from its distinctive seed heads, which resemble the tail feathers of a duck. The leaves of the plant are also quite unique, being much wider than most other types of grass.
How to get rid of quackgrass
- Grow a thick lawn like mentioned above, this will cause crowding and slowly starve the invasive grass
- Apply a selective herbicide
Smooth Bromegrass
Smooth bromegrass (Bromus inermis) is a perennial grass that’s native to Europe and Asia but has been introduced to North America. It’s often used as a forage crop or turfgrass but can become an invasive problem in some areas.
Smooth bromegrass is a perennial grass that thrives in difficult environments (including cold climates). It also spreads via rhizomes in the ground and has a strong root system. This introduced grass will quickly overtake a thin lawn.
Smooth bromegrass is also harmful since it encourages excessive growth and destroys surrounding vegetation. Smooth bromegrass has a fast growth rate and a robust root system, making it perfect for ground cover. It can also be used as hay.
How to get rid of smooth bromegrass
- Grow a thick lawn from the start to prevent it from growing in the first place
- Apply a selective herbicide
Slender Rush
Slender rush (Juncus tenuis) is a type of invasive grass that’s native to Europe but has been introduced to North America. It’s often found in wet areas such as marshes, swamps, and ditches.
Slender rush is a fast-growing plant that can quickly spread and take over an area. It propagates via seeds which are dispersed by the wind and ground tubers. The plant also forms dense mats which can crowd out other vegetation.
How to get rid of slender rush
- When slender rush appears, remove it with herbicides and uproot it by hand. However, do it from the roots to avoid regrowth.
- Alternatively, you can cut your grass on a regular basis to prevent the plant from developing beyond the seedling stage.
Tall Fescue
Tall fescue (Festuca arundinacea) is a type of grass that’s native to Europe and Asia but is now in North America. It’s often used as a forage crop, turfgrass, or erosion control.
Tall fescue is a pesky weed that flourishes in dense clumps and extends through rhizomes underground. It’s resistant to severe weather conditions, making it difficult to kill. In fact, its leaves resemble succulent stems. Therefore, when this weed infests a lawn, the grass cannot compete and eventually dies.
How to get rid of tall fescue
- The greatest approach to combat tall fescue is to solarize it, which is when you cover parts of your lawn with fabric such as nylon paper for extended periods of time.
Conclusion
Invasive grasses can be a big problem for both homeowners and gardeners. They can quickly take over an area and crowd out other plants. There are several ways to get rid of invasive grasses, but the best approach is to prevent them from growing in the first place. Let’s summarise:
- The most common invasive grass types are Annual Bluegrass, Alexandergrass, Crabgrass, Green Foxtail, Nutsedge, Quackgrass, Smooth Bromegrass, Slender Rush and Tall Fescue
- Invasive grass are weeds that compete with your lawn turf and plants for nutrients
- They can cause damage to lawns if appropriate preventative actions are not carried out
- You can get prevent most invasive grass by growing thicker lawns, using baking soda and certain herbicides
