A mole cricket has a face only a mother could love. They are so strange looking, in fact, that in the past week I’ve had two people ask me what they were. They have large, round, helmet-like heads, undersized eyes, and massive front claws used for digging. Unlike your garden-variety crickets, which really don’t cause any major damage to home landscapes, the mole cricket is quite the turfgrass menace. Instead of hopping about aboveground, they tunnel beneath the lawn and feast on the roots and leaves of grass, often destroying entire yards. They are also vegetable pests, going after tomatoes, cabbage, and peppers.
A young mole cricket. Its round head and large front claws distinguish it from other cricket species. Photo credit: Lucy Adams StevensonA) Horizontal and B) vertical view of a generalized tawny mole cricket burrow showing 1) horn, 2) 1st constriction, 3) bulb, 4) 2nd constriction, 5) turn-around, 6) surface tunnel, and 7) deep tunnel. Figure 1 from Nickerson et al. 1979. Ann. Entomol. Soc. Am. 72(3):438-440.
Mole crickets spend most of their time below ground and form burrows for hiding, laying eggs, and traversing through their territory. In mating season, males create a monotone song that averages 88 decibels—as loud as a motorcycle! The call comes from their burrows, which have funnel-like openings that expand at the surface, creating amplification comparable to a horn.
Beneficial larra wasp parasitizing a tawny mole cricket. Photo credit: UF IFAS
The tawny mole cricket (Neoscapteriscus vicinus) is the most common to our area and is an invasive species from South America. UF IFAS has had a specific research program related to mole cricket management since the late 1970’s. One successful outcome of this program has been the introduction of a biological control species, the larra wasp (Larra bicolor). The wasp manages mole cricket populations by stinging and temporarily paralyzing crickets. A female will then deposit an egg into the mole cricket’s body. The cricket recovers and goes about its daily routine until the egg hatches, at which point the larval wasp feeds on and eventually kills the mole cricket. Along with the wasp and release of flies and a nematode that also manage mole crickets, the biocontrol methods introduced between the 1980’s and 2004 have resulted in a 95% reduction in mole cricket populations in north Florida.
If you are seeing mole crickets, you can attract larra wasps to your property by planting shrubby false buttonweed or partridge pea plants, which the wasps feed on. If you have serious damage from mole crickets, check out this thorough Mole Cricket Integrated Pest Management Guide, or contact the horticulture agent at your local county extension office to get a site-specific recommendation for management.
It amazes me that even under flood conditions, people still water their lawns.
I’m sure you’ve seen it too – we get enough rain to cause some areas to flood and yet you see irrigation systems going full blast.
Lawn irrigation should be applied on an as needed basis. Credit: Larry Williams
We should water our lawns, landscapes and gardens on an as-needed basis. The way that some people water their lawns is as logical as saying that a pet dog needs a drink of water at 4 p.m. everyday. This is not true. When watering, we are simply replacing water that is lost. This is true when we drink water ourselves, when we provide water for a pet dog, or when we provide water for our lawns, landscapes and gardens.
An irrigation system is a great tool when used to supplement rainfall. Irrigating too much not only wastes water but it also is the cause for many lawn problems such as shallow, weak root systems, leaching of fertilizer and numerous lawn diseases. Cutting the irrigation timer to off and operating the system manually will solve many lawn problems.
Also, there are tools to prevent an irrigation system from coming on during rain or when adequate rainfall has occurred. As a matter of fact, it has been state law in Florida for every automatic irrigation system to have a rain shutoff device installed since 1991.
Florida Statutes, Chapter 373.62 – Water conservation; automatic sprinkler systems states, “Any person who purchases and installs an automatic lawn sprinkler system after May 1, 1991, shall install a rain sensor device or switch which will override the irrigation cycle of the sprinkler system when adequate rainfall has occurred,”
Rain sensors are available, inexpensive and are not difficult to install. Rain shutoff devices really do work when installed properly. If you do not feel qualified to install such a devise on an existing system, check with a reputable irrigation company.
Water only when lawn indicates that water is needed. When the grass needs water, leaf blades fold along the midrib – like a book closing, footprints remain in the lawn long after being made and the lawn turns grayish in spots, indicating it needs water.
When 30 to 40 percent of the lawn shows these signs of water need, turn the irrigation system on and let it run long enough to apply one-half to three-quarters inch of water. Don’t water again until the lawn begins to show these signs of water need. Watering this way will develop a deep-rooted lawn and landscape. Here’s a UF/IFAS Extension link with more information on lawn and landscape irrigation. https://gardeningsolutions.ifas.ufl.edu/care/irrigation
Now that we are moving into warmer soil temperatures, weak areas in lawns will have a better chance of making some recovery. However, this is highly dependent on whether or not correct lawn maintenance practices are followed. These practices include fertilizing, mowing and watering correctly.
Warmer soil and correct care help improve weak lawns
Many North Florida lawns came out of winter weak and thinning this spring. In areas of the lawn where there is at least sixty percent cover of the desirable type of lawn grass, recovery is possible. But where there is less than sixty percent desirable cover, reestablishment should be considered.
Applying the correct type and amount of fertilizer will promote lawn recovery. To maintain a healthy Florida lawn, it’s critical to use a fertilizer with adequate potassium. In most cases, use a lawn fertilizer with equal amounts of nitrogen (first number) and potassium (third number) such as 8-0-8, 10-0-10, 15-2-15 or similar analysis. Phosphorus (second number) should be low or zero unless you have the results of a reliable soil test indicating that more phosphorus is needed. Err on the side of being light handed when applying fertilizer to the lawn. In North Florida, most lawns will do just fine with an application in spring no earlier than mid-April and a second application in summer no later than mid-September.
Follow these mowing practices for a healthy lawn.
Never remove more than 1/3 of the leaf blade height at any one time.
Here’s the recommended mowing height in inches for each lawn grass: bahia – 3 to 4; centipede – 1.5 to 2; standard St. Augustine cultivars – 3 to 4; dwarf St. Augustine cultivars (Captiva and Seville) – 2 to 3; zoysia cultivars suitable for home lawns- 2 to 2.5; bermuda – .5 to 1.5.
Keep mower blades sharp.
Follow these irrigation practices for a deeper rooted and drought tolerant lawn.
Turn your automatic sprinkler system off and learn to operate it manually on an as-needed basis. Your lawn needs water when leaf blades start to fold in half lengthwise or when footprints remain visible in the lawn long after being made. Irrigate when at least 30% of the lawn shows these signs of water need.
Apply ½ – ¾ inch of water when you do irrigate. Place empty, straight-sided cans in the area being irrigated to see how long it takes to reach this amount.
Irrigate during early morning for more efficient water use and to minimize lawn diseases.
Here is a link to a UF/IFAS Extension publication on Best Management Practices for a Florida lawn. http://edis.ifas.ufl.edu/ep236
Written by: Khadejah Scott, Horticulture, Agriculture, & Natural Resources Extension Agent, UF/IFAS Extension – Wakulla County
A well-manicured lawn not only enhances the beauty of your property but also provides a welcoming outdoor space. In North Florida, where warm weather and abundant rainfall create ideal conditions for lush green lawns, proper mowing practices play a crucial role in maintaining a healthy and vibrant landscape. With the right techniques and considerations tailored to the unique characteristics of this region, you can achieve a pristine lawn that becomes the envy of the neighborhood. In this article, we will explore essential tips and insights for mowing your North Florida lawn, helping you unleash the full potential of your outdoor haven while ensuring its long-term health and sustainability.
Mowing a lawn. Photo Credit: University of Florida/IFAS
Mowing Heights
The turfgrass species’ growth pattern and leaf width influence the ideal mowing height. Grass species that grow horizontally and have narrow leaf blades are often cut lower than grasses that grow upright and have wider leaf blades. Because of its numerous tiny leaf blades, Bermudagrass is an example of a plant that is mowed at low heights. St. Augustinegrass, on the other hand, has wider leaf blades and is cut at a higher height. Rooting depth is also influenced by mowing, with deeper roots developing in response to higher mowing heights. Greater resistance to drought, insects, disease, nematodes, temperature stress, poor soil conditions, nutritional deficiencies, and traffic are benefits of the deeper root system. The main cause of turf damage is frequent mowing below the suggested heights for each species, which should be avoided.
Mowing Frequency
The frequency of lawn mowing is determined by the rate at which the grass grows, which is influenced by various factors such as the type of grass, time of year, weather conditions, and the level of maintenance. In North Florida, the need for mowing during winter months may vary depending on the climate and the type of grass present. Grasses like bahiagrass, which require less maintenance, may primarily be mowed to remove seedheads rather than cutting the leaf blades. To maintain a healthy lawn, it is recommended to mow frequently enough to remove no more than one-third of the blade height at a time. Preserving an ample amount of leaf surface is crucial to allow for photosynthesis, especially when the grass is exposed to environmental or site-related stresses.
A lawn up close. Photo Credit: University of Florida/IFAS
Using Grass Clippings
Leaving grass clippings on the lawn is generally beneficial as it aids in recycling nutrients and organic matter, while reducing waste in landfills. When lawns are regularly mowed, clippings pose minimal issues. Microbes in the soil readily decompose the clippings, returning valuable organic matter and nutrients to the soil without contributing to thatch buildup under normal conditions. However, infrequent mowing can lead to excess clippings, resulting in clumping and potential thatch formation. Excessive thatch can create various problems, including reduced water infiltration, increased risk of pests and diseases, and diminished turf quality. To mitigate environmental concerns, it is crucial to sweep up any grass clippings from hard surfaces like sidewalks or driveways. These clippings contain nutrients that, if washed into storm drains or water bodies, can contribute to water pollution. By sweeping them back onto the lawn, the grass can benefit from the nutrients while minimizing environmental impact.
Proper mowing practices are essential for maintaining a healthy and vibrant lawn in North Florida’s unique climate. Understanding the growth patterns of different grass species, adjusting mowing frequency accordingly, and leaving clippings on the lawn to recycle nutrients are key aspects of lawn maintenance. By following these guidelines, homeowners can achieve a well-manicured lawn that enhances the beauty of their property while promoting environmental sustainability. Additionally, regular mowing helps prevent thatch buildup, ensures optimal photosynthesis, and reduces the risk of pest and disease infestations. By implementing these best practices, residents of North Florida can enjoy a lush, resilient, and visually appealing lawn that serves as a welcoming outdoor space for years to come. Remember, mowing is not just a chore but an art that contributes to the overall health and aesthetics of your landscape. UF/IFAS provides a wealth of information online regarding maintaining a well-manicured lawn. For any questions or concerns, be sure to consult with your local UF/IFAS Extension Office.
Does your yard have patches of dead grass or areas that look thin and weak? The last two summers of heavy rain and the stress of December’s freezing weather have contributed to widespread outbreaks of Take-All Root Rot, a soil-inhabiting fungus Gaeumannomyces graminis var. graminis that causes yellow grass patches ranging in diameter from a few inches to more than 15 feet. The symptoms first appear in the spring, but disease can persist all summer and survive the winter. Over time the entire area dies as the root system rots away.
The pathogen is naturally present on warm-season turfgrass roots. High rainfall and stressed turfgrass trigger the disease. Because the roots are affected, they are not able to efficiently obtain water or nutrients from the soil, nor are they able to store the products of photosynthesis, which result in the loss of color in the leaves. By the time the leaf symptoms appear, the pathogen has been active on the roots for several weeks, probably longer; potentially years. If the turfgrass is not stressed, leaf symptoms may never be observed. To confirm the presence of TARR, submit a sample to the UF Pathology Lab.
This disease is very difficult to control once the above-ground symptoms are observed. Measures that prevent or alleviate stress are the best methods for controlling the disease. Any stress (environmental or man-made) placed on the turf weakens it, making it more susceptible to disease. Remember, that every maintenance practice, fertilizer application, and chemical (especially herbicide), application has an impact on turfgrass health.
Cultural practices that impact the level of stress experienced by a lawn include: proper turfgrass species selection; mowing at the correct height; irrigation timing, frequency and volume; fertilizer nitrogen and potassium sources and application quantities; thatch accumulation; and soil compaction issues. The selection of turfgrass species should be based on existing soil pH, sunlight exposure, use of the area and planned maintenance level.
Mower blades must be sharp to avoid tearing of the leaves. Additionally, turfgrasses that are cut below their optimum height become stressed and more susceptible to diseases, especially root rots. When any disease occurs, raise the cutting height. Scalping the grass damages the growing point. Raising the cutting height increases the green plant tissue available for photosynthesis, resulting in more energy for turfgrass growth and subsequent recovery from disease.
The amount of water and the timing of its application can prevent or contribute to disease development. Most fungal pathogens that cause leaf diseases require free water (rainfall, irrigation, dew) on the leaf to initiate the infection process. Irrigating every day for a few minutes is not beneficial for the turfgrass because it does not provide enough water to the root zone, but it is beneficial for turfgrass pathogens. It is always best to irrigate when dew is already present, usually between 2 and 8 a.m., and then only apply enough water to wet the root zone of the turfgrass. If an area of the lawn has an active fungus, washing or blowing off the mower following use will reduce the spread of the disease to unaffected areas.
Excessively high nitrogen fertility contributes to turfgrass diseases. The minimum amount required for the grass species should be applied. Potassium (K) is an important component in the prevention of diseases, because it prevents plant stress. Application of equal amounts of nitrogen and potassium is recommended for turfgrass health. When turfgrass roots are damaged from disease, it is beneficial to apply nutrients in a liquid solution. However, nitrate-nitrogen increases the severity of diseases, so its use should be avoided when possible. Ammonium-containing fertilizers are the preferred nitrogen sources. Heavy liming has also been linked to increases in Take-All Root Rot. Since most turfgrasses can tolerate a range of pH, maintaining soil at 5.5 to 6.0 can suppress the development of the pathogen. When the disease is active, frequent foliar applications of small amounts of nutrients is necessary to keep the turfgrass from declining.
Additional maintenance practices that need to be addressed are thatch removal and reduction of soil compaction. Excessive thatch often causes the mower tires to sink, which can result in scalping and reducing the amount of leaf tissue capable of photosynthesizing. Thatch and compacted soil prevent proper drainage, resulting in areas remaining excessively wet, depriving root systems of oxygen.
Since recovery of Take-All damaged turfgrass is often poor, complete renovation of the lawn may be necessary. Removal of all diseased tissue is advised. As a native, soil-inhabiting pathogen, Take-All-Root-Rot cannot be eliminated. But, suppression of the organism through physical removal followed by proper cultivation of the new sod is critical to the establishment of a new lawn. Turfgrass management practices, not chemicals, offer the best control of the disease.
It is acceptable to use fungicides on a preventative basis while rooting in the sod. Azoxystrobin, fenarimol, myclobutanil, propiconazole, pyraclostrobin, thiophate methyl, and triadimefon are all fungicides that can be utilized to prevent disease development while having to excessively irrigate newly laid sod. Ideally, the turf area should be mowed and irrigated prior to a fungicide application. Unless the product needs to be watered in, do not irrigate for at least 24 hours after a chemical treatment. Do not mow for at least 24 hours, to avoid removal of the product attached to the leaf blades.
Now that we have added another major stress with the recent heavy rain, it will be very important to continue monitoring the turf and being cautious about the cultural practices being used. Take-All Root Rot is likely to flourish. Do not encourage its development.
If the damaged areas are small, it may be possible to encourage turfgrass runners to grow back into the space. Application of 50/50 blends of sphagnum moss and course white sand can be used to top-dress the damage areas. Add no more than 1-inch of the mixture per application. After the stolons have crept into the voids and received a mowing, more top-dressing can be applied. Repeat until the grass stops growing in the fall. Fungicides applied in the spring and fall will help to keep the Gaeumannomyces graminis var. graminis suppressed.
