Fescue lawns, known for their durability and resilience, are a popular choice for many homeowners. However, even the toughest fescue stands can fall prey to other, more aggressive grass types. Understanding which grasses pose the biggest threat and how to combat them is crucial for maintaining a healthy, fescue-dominant lawn. This article will delve into the grasses that can effectively “choke out” fescue, exploring their characteristics, competitive advantages, and the best strategies for keeping them at bay.
Understanding the Fescue Family and Its Vulnerabilities
Fescue isn’t a single grass, but rather a genus encompassing several species commonly used in lawns. Tall fescue, with its coarse texture and deep roots, is particularly widespread, especially in transition zones. Fine fescues, including creeping red fescue, chewings fescue, and hard fescue, offer finer textures and better shade tolerance. Despite their strengths, fescues have vulnerabilities.
Fescue’s Weaknesses: Sunlight, Moisture, and Competition
While tall fescue is known for its drought tolerance, it still requires adequate moisture, especially during establishment. Fine fescues, while shade-tolerant, can struggle in full sun and poorly drained soils. Crucially, all fescues can be outcompeted by more aggressive grasses, especially when stressed by improper mowing, fertilization, or watering practices. Consistent, proper lawn care is the first line of defense against invasive grasses.
The Usual Suspects: Grasses That Challenge Fescue Dominance
Several grass species are notorious for their ability to invade and ultimately dominate fescue lawns. These invaders often exploit weaknesses in the fescue stand, spreading rapidly and creating unsightly patches.
Bermudagrass: The Southern Aggressor
Bermudagrass, a warm-season grass prized for its heat and drought tolerance, is a formidable opponent. Its aggressive growth habit, enabled by both rhizomes (underground stems) and stolons (aboveground stems), allows it to quickly spread and choke out fescue, particularly in warmer climates or during hot summers. Bermudagrass thrives in conditions where fescue struggles.
Bermudagrass’s superior heat tolerance gives it a significant advantage during the summer months. It actively grows while fescue often slows down, allowing it to spread rapidly. Furthermore, Bermudagrass tolerates close mowing, which can further weaken fescue and give Bermudagrass a competitive edge.
Zoysiagrass: The Slow-Motion Invader
Like Bermudagrass, Zoysiagrass is a warm-season grass that can outcompete fescue, though its spread is generally slower. Zoysiagrass is incredibly dense, forming a thick mat that can suppress fescue growth by blocking sunlight and nutrients.
While Zoysiagrass establishes more slowly than Bermudagrass, its dense growth habit eventually makes it highly competitive. Its excellent wear tolerance also makes it suitable for high-traffic areas, where fescue may be more susceptible to damage.
Kentucky Bluegrass: The Cool-Season Competitor
Kentucky Bluegrass (KBG) is a cool-season grass that can compete with fescue, especially in northern regions or during cooler periods of the year. While not as aggressive as Bermudagrass or Zoysiagrass, KBG can spread through rhizomes, gradually encroaching on fescue stands.
Kentucky Bluegrass’s finer texture and ability to spread contribute to its competitive advantage. It often thrives in well-maintained lawns, where it can gradually displace fescue, creating a mixed stand or, in some cases, eventually dominating the lawn.
Annual Bluegrass (Poa annua): The Opportunistic Weed
Annual Bluegrass (Poa annua) is a common weed grass that can quickly infest fescue lawns, especially in areas with compacted soil or poor drainage. It’s an annual grass, meaning it completes its life cycle in one year, but it produces abundant seeds, ensuring its persistence.
While Annual Bluegrass typically dies off during hot summers, its rapid growth and prolific seed production can create dense patches that weaken fescue. Its shallow roots also compete for water and nutrients, further stressing the fescue stand.
Rough Bluegrass (Poa trivialis): The Shade Lover
Rough Bluegrass (Poa trivialis) is another weed grass that can invade fescue lawns, particularly in shady or damp areas. It has a lighter green color and a coarser texture than desirable fescue varieties.
Rough Bluegrass thrives in moist, shady conditions, where fescue may struggle. Its aggressive growth habit allows it to quickly spread and form dense patches, often displacing fescue in these problem areas.
Creeping Bentgrass: The Putting Green Invader
Creeping Bentgrass is a fine-textured grass often used on golf course putting greens. However, it can also invade home lawns, particularly those with poor drainage or excessive thatch.
Creeping Bentgrass spreads aggressively through stolons, forming dense mats that can smother fescue. Its fine texture and low growth habit contrast sharply with the coarser texture of fescue, making it visually unappealing in a home lawn setting.
Strategies for Preventing and Controlling Invasive Grasses
Preventing invasive grasses from choking out fescue requires a multifaceted approach that focuses on maintaining a healthy fescue stand and implementing targeted control measures.
Promote Healthy Fescue Growth
A dense, healthy fescue lawn is the best defense against invasive grasses. This involves proper mowing, fertilization, watering, and aeration practices.
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Mowing: Mow fescue at the correct height for the specific variety. Tall fescue typically prefers a mowing height of 2-3 inches, while fine fescues can be mowed slightly shorter. Avoid scalping the lawn, as this can weaken the fescue and create opportunities for invasive grasses to establish. Never remove more than 1/3 of the grass blade at a time.
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Fertilization: Fertilize fescue according to soil test recommendations. A balanced fertilizer that provides adequate nitrogen, phosphorus, and potassium is essential for healthy growth. Avoid over-fertilizing, as this can promote excessive top growth and weaken the root system.
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Watering: Water fescue deeply and infrequently, allowing the soil to dry out slightly between waterings. This encourages deep root growth, making the fescue more drought-tolerant and competitive. Avoid frequent, shallow watering, which can promote shallow root growth and create favorable conditions for some invasive grasses.
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Aeration: Aerate the lawn annually to alleviate soil compaction and improve drainage. Core aeration, which involves removing small plugs of soil, is particularly effective. Aeration allows air, water, and nutrients to penetrate the soil more easily, promoting healthy root growth and reducing the risk of invasive grass infestations.
Targeted Weed Control Measures
In addition to promoting healthy fescue growth, targeted weed control measures may be necessary to manage invasive grasses.
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Hand-Pulling: For small infestations of annual bluegrass or other weeds, hand-pulling can be an effective control method. Be sure to remove the entire plant, including the roots, to prevent regrowth.
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Herbicides: Herbicides can be used to control invasive grasses, but it’s important to select a product that is safe for use on fescue and effective against the target grass. Pre-emergent herbicides can prevent weed seeds from germinating, while post-emergent herbicides can kill existing weeds. Always read and follow the label instructions carefully when using herbicides.
- Selective Herbicides: These are designed to target specific weed grasses without harming the desirable fescue. Research and choose the appropriate selective herbicide for the specific invasive grass you’re trying to control.
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Non-Selective Herbicides: These herbicides kill all vegetation they contact. They can be useful for spot-treating small patches of invasive grass, but they should be used with caution to avoid damaging the surrounding fescue.
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Solarization: In cases of severe infestation, solarization can be used to kill all vegetation in a specific area. This involves covering the area with clear plastic during the hottest part of the summer. The heat trapped under the plastic will kill the grass and weed seeds.
Specific Strategies for Common Invasive Grasses
Controlling specific invasive grasses often requires tailored strategies.
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Bermudagrass and Zoysiagrass: These warm-season grasses are notoriously difficult to control in cool-season lawns. Repeated applications of selective herbicides may be necessary. In severe cases, non-selective herbicides may be required, followed by reseeding with fescue.
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Kentucky Bluegrass: Managing Kentucky Bluegrass in a fescue lawn can be challenging. Over-seeding with a shade-tolerant fescue blend, particularly in areas where KBG is prevalent, can help increase fescue density.
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Annual Bluegrass and Rough Bluegrass: Improving drainage and alleviating soil compaction can help reduce infestations of these weed grasses. Pre-emergent herbicides can prevent annual bluegrass from germinating, while post-emergent herbicides can control existing plants.
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Creeping Bentgrass: Improving drainage and reducing thatch can help control creeping bentgrass. Selective herbicides are available, but they may require multiple applications.
Overseeding to Thicken Fescue Stands
Overseeding with fescue in the fall is an effective way to thicken the lawn and increase its competitiveness against invasive grasses. Choose a high-quality fescue seed blend that is adapted to your local climate and soil conditions. Proper soil preparation is crucial for successful overseeding.
Core aeration before overseeding can improve seed-to-soil contact. After seeding, keep the soil moist until the new grass seedlings have established. Avoid heavy traffic on the lawn until the new grass is well-established.
The Importance of Professional Lawn Care
While many lawn care tasks can be performed by homeowners, professional lawn care services can provide valuable expertise and resources for managing invasive grasses. Lawn care professionals have access to specialized equipment and herbicides that are not available to the general public. They can also develop a customized lawn care plan that is tailored to your specific needs and lawn conditions.
A professional lawn care service can help you identify invasive grasses, assess the severity of the infestation, and develop a comprehensive control strategy. They can also provide regular lawn maintenance services, such as mowing, fertilization, and aeration, to help keep your lawn healthy and resistant to invasive grasses.
Conclusion: Maintaining a Fescue Fortress
Maintaining a fescue lawn free from invasive grasses requires vigilance, knowledge, and consistent effort. By understanding the vulnerabilities of fescue, recognizing the common invaders, and implementing effective prevention and control strategies, you can create a healthy, thriving fescue lawn that withstands the challenges of unwanted grass species. Remember that a dense, well-maintained fescue stand is the best defense against invasion. When faced with persistent problems, seeking professional assistance can provide the expertise and resources needed to regain control of your lawn and enjoy its beauty for years to come. Proactive measures and consistent care are key to conquering the “choking” threat and ensuring your fescue lawn remains a lush, green haven.
What makes fescue so difficult to get rid of?
Fescue’s resilience stems from its deep root system and bunch-forming growth habit. These characteristics allow it to withstand drought conditions and compete effectively for nutrients. Furthermore, some varieties of fescue are bred for hardiness, making them even more challenging to eradicate naturally. Chemical control methods often require multiple applications due to this robust nature.
The dense clumps formed by fescue can also prevent other grasses from germinating and establishing. This competitiveness allows fescue to dominate a lawn over time, making it difficult for desired grasses to take hold. The extensive root system can draw resources away from newly seeded or struggling grasses, further hindering efforts to convert the lawn.
Can any grass type completely choke out fescue naturally?
No single grass type can definitively “choke out” established fescue naturally, without intervention or management strategies. While certain aggressive grass species like Bermuda or Zoysia are highly competitive, they typically spread through runners and rhizomes, gradually encroaching upon fescue. This is a slow process, often requiring several years and specific environmental conditions favorable to the invasive grass.
However, selecting a grass type adapted to your local climate and soil conditions can give it a competitive advantage. Consistent overseeding with the preferred grass, coupled with proper fertilization and watering, can gradually weaken the fescue over time, allowing the desired grass to eventually dominate the lawn. This approach requires patience and diligence, focusing on creating an environment that favors the desired grass species.
Will herbicides effectively eliminate fescue without harming other grasses?
Selective herbicides designed to target specific grass types can be used to control fescue without harming some other desirable grasses, but their effectiveness depends on careful application and the type of fescue being targeted. “Selective” in this context means that the herbicide is formulated to impact only certain plant species while sparing others. However, the degree of selectivity varies, and some level of damage to desirable grasses is possible.
Non-selective herbicides, like glyphosate, kill all vegetation they contact. Therefore, using non-selective herbicides to eliminate fescue requires extreme caution, often necessitating spot treatments or complete renovation of the affected area. Protect desirable grasses with barriers or carefully apply the herbicide directly to the fescue clumps to minimize unintended damage.
How does soil health impact the success of replacing fescue with other grasses?
Healthy soil is crucial for the successful establishment of any new grass type and the eventual replacement of fescue. Proper soil composition provides essential nutrients, allows for adequate drainage, and promotes strong root development. Soil testing helps determine nutrient deficiencies and pH imbalances that may hinder the growth of the desired grass.
Amending the soil based on the test results, such as adding compost or other organic matter, can significantly improve its fertility and structure. Good drainage prevents waterlogging, which can stress new grass seedlings and favor fescue. Healthy soil creates an environment where the new grass can thrive and outcompete the fescue, leading to a successful lawn conversion.
What cultural practices can help weaken fescue and encourage other grasses?
Several cultural practices can weaken fescue and promote the growth of other grasses. Regular mowing at the correct height for your desired grass species helps favor its growth habit over that of fescue. Overseeding with the desired grass type in the fall or spring provides new seedlings a chance to establish and compete with the existing fescue.
Proper fertilization provides the necessary nutrients for the desired grass to thrive. A balanced fertilizer promotes healthy growth and strengthens the grass’s ability to compete with fescue. Aeration helps improve soil drainage and allows roots to access nutrients and water more effectively, further promoting the health of the desired grass species.
Is it better to completely renovate the lawn or try to gradually replace the fescue?
The decision to completely renovate the lawn versus gradually replacing the fescue depends on several factors, including the severity of the fescue infestation, your budget, your timeline, and your tolerance for a less-than-perfect lawn during the transition. Complete renovation, involving killing all existing vegetation and re-seeding or sodding, provides the fastest and most effective solution for completely replacing fescue. However, it also requires more upfront investment and disruption.
Gradual replacement, through overseeding, cultural practices, and potentially spot herbicide treatments, is a more cost-effective and less disruptive approach. However, it takes significantly longer and may require consistent effort over several seasons to achieve the desired results. If you’re willing to be patient and manage expectations, gradual replacement can be a viable option.
Can a professional lawn care service help with fescue control and grass replacement?
Yes, a professional lawn care service can provide valuable expertise and assistance with fescue control and grass replacement. These services have the knowledge, experience, and specialized equipment to properly diagnose the problem, recommend the most effective solutions, and implement them efficiently. They can perform soil tests, identify the specific type of fescue, and recommend the appropriate grass species for your area and soil conditions.
Professionals can also apply herbicides safely and effectively, ensuring minimal damage to desirable grasses. They can perform aeration, overseeding, and fertilization services, and provide ongoing maintenance to ensure the successful establishment of the new grass. While hiring a lawn care service involves an expense, the expertise and results they provide can often justify the cost, especially for homeowners who lack the time, knowledge, or equipment to tackle the problem themselves.