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.
Centipedegrass is a low maintenance turfgrass for North Florida landscapes. Scientists from Georgia also found an added benefit when the grass is in flower. Learn about the specific insects found visiting the flowers of centipedegrass.
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
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.
Turfgrass lawns are popular. Homes and businesses alike often have at least some portion of their landscape dedicated to turf, and while it is often maligned, turfgrass does have some benefits when used and managed responsibly.
Well-managed turfgrass, like this centipedegrass lawn, can be a sustainable and attractive option for landscapes. Photo credit: Dr. J. Bryan Unruh, UF/IFAS
Detractors of lawns may argue that lawn maintenance uses water, gasoline (for mowers), and pesticides, all while contributing little to the environment. The varieties of grass we use in the Florida panhandle are not native to the area, with the possible exception of St. Augustinegrass. Planting anything – and especially non-native plants – in a monoculture limits biodiversity and does not support native wildlife. These complaints may be valid in cases, but this does not mean there is no room for turfgrass in the landscape. Instead, it is important to design landscapes appropriately and maintain lawns sustainably. The ideal of a lush, completely weed and insect free, beautifully green all year long, neatly trimmed magazine-cover style swath of grass is unrealistic.
That being said, what are lawns useful for? What are the benefits of turfgrass?
When managed properly, turfgrass can be used for numerous beneficial reasons. Grass is a plant, which means that it has roots to stabilize soil, slow runoff, and filter water. It keeps down dust, mitigates heat, and can outcompete unwanted weeds. It is useful as a surface for recreation, and can add aesthetic value to a landscape. Turf does, in fact, support wildlife to a certain degree as well, as the insects that live in and feed on it can serve as food for birds and other animals.
Improper irrigation can cause big problems with turf and lead to wasted water, but turf can help to slow down runoff and absorb excess nutrients.
Artificial turf is sometimes considered as an alternative to grass, but the differences can serve as an example of the benefits of turf. Artificial turf can heat up in the hot Florida sun. Where it is used on athletic fields, it may need to be irrigated to both cool it and keep dust down. The water used for this has much more opportunity to run off the site, as the artificial turf has no roots to slow it down. Turfgrass is also much softer than its man-made replacements; sports fields with artificial turf have a higher incidence of injury than those planted with grass.
Lawns must be managed well, however, as has been stated before. Proper species selection (whether bahia, centipede, Bermuda, St. Augustine, or Zoysia), establishment, irrigation, fertilization, and mowing practices all contribute to making turfgrass a sustainable option. You can find information on all of these in our EDIS publications, which are linked to above, or contact your local Extension office for help. If turfgrass still seems like an unpalatable option, you can also find information on turfgrass alternatives and more on Florida Friendly Landscaping. Keep your expectations reasonable and your landscapes sustainable!
Weeds are basically unwanted plants or plants growing out of place. Proper identification and some understanding of how and why weeds are present in a lawn are important when selecting the best management tactics. All turf weeds can be grouped into one of three life cycles: annual, biennial, or perennial.
Annual: Produces seeds during one season only
Biennial: Produces seeds during two back-to-back seasons
Perennial: Produces seeds over many seasons
Knowing the types of weed previously present in an area also can help one to be better prepared and what control measures to employ in the future.
Weeds may appear in multiple categories, either broadleaf, grass, or Sedges/rushes.
Winter annual weeds in lawn in early spring. Photo credit: Larry Williams
Broadleaves, or dicotyledonous plants, have two cotyledons (seed leaves) when the weed seed germinates.
Appearance: Broad, flat leaves with net-like veins and usually have showy flowers.
Common types: Clover, ground ivy, dandelions, chickweed, plantain, henbit, beggarweed.
Grasses are monocotyledonous plants that have only one cotyledon, or seed leaf, present when seedlings emerge from the soil.
Appearance: Narrow leaves with parallel veins in their true leaves. Hollow rounded stems.
Common types: crabgrass, goosegrass, crowfoot grass, bull grass, annual bluegrass, alexander grass, cogon grass, torpedo grass, and smut grass.
Sedges/rushes. Both favor a moist habitat. Appearance: triangular-shaped, solid stems, while rush stems are round and solid.
Common types: yellow and purple nutsedge and, to some degree, globe, Texas, annual, and water sedge.
One of the first steps in managing weeds is to have a healthy dense lawn/ turf to provide shade that prevents seed germination. Having a healthy lawn depends on turf species selected – making sure you put the right plant and right place. Other factors that influence a heathy turf and a reduced amount of weeds include proper cultural control, fertilizing regularly, mowing at the appropriate height, watering deeply, reducing traffic, pest control, and sanitation. If you only have a few bothersome weeds in your lawn, you may be able to dig them up by hand—but if your lawn is overrun with weeds, you may need to start from scratch. If you decide to start from the beginning, you have a choice ahead of you. Do you want to lay down seed or sod? There are pros and cons to each.
Seed
Pros: Less expensive, more variety
Cons: Takes longer to germinate, can only lay at certain times of year depending on grass type
Sod
Pros: Instant grass, can lay any time of year, requires little maintenance
Cons: More costly, less variety in grass can mean less healthy lawn overall
To prepare the soil after either method, make sure you till it down to roughly 6 to 8 inches.
Supporting information for this article can be found in the UF/IFAS EDIS publications (Weed management for Florida lawns) https://edis.ifas.ufl.edu/publication/EP141 or contact your local Extension Office!
