by Mary Salinas | Oct 14, 2015
Cogongrass dominating the landscape. Photo credit: Charles T. Bryson, USDA Agricultural Research Service, Bugwood.org.
A U.S. Forest Service grant is again available to assist non-industrial private landowners with the cost of controlling cogongrass. Applications will be accepted starting October 15, 2015. The program reimburses landowners for 50% of the cost for two consecutive years with a maximum reimbursement of $10,000 for each year.
Cogongrass is one of the worst invasive plant species in Northwest Florida as it marches through natural areas and literally chokes out our desirable native vegetation as it goes. The underground rhizomes continually expand patches of the grass in every direction and its prolific seed production carries infestations to new areas.
Note the off center midrib along the leaf blade. Photo credit: Chris Evans, Illinois Wildlife Action Plan, Bugwood.org.
There are several ways to accurately identify cogongrass. The leaf blades are flat with serrated edges and tend to be yellowish-green in color. The midrib which runs lengthwise up each leaf blade is white and is distinctly off-center. The seed head which arises in the spring is a fluffy white plume. Since it spreads through rhizomes, cogongrass is often seen in expanding circular patches.
The fluffy white plume of the seedhead. Photo credit: Chris Evans, Illinois Wildlife Action Plan, Bugwood.org.
If you need assistance with the identification of cogongrass, please consult your local Extension office.
For more information:
Cogongrass Treatment Cost-Share Program
Cogongrass (Imperata cylindrica) Biology, Ecology, and Management in Florida Grazing Lands
by Matt Lollar | Sep 23, 2015
Armyworms come in a wide range of colors and sizes. A few of the prominent species living in Florida are beet, southern, and fall armyworms. And the term “living” is not an exaggeration, because Florida is one of the lucky states where it is warm enough for armyworms to overwinter. They are the snowbirds that never leave!
Armyworm damage on a lawn. Credit: Purdue University
Armyworms are notorious for unanticipated invasions. They feed on most turfgrass species and most vegetable crops, but they prefer grassy vegetable crops such as corn. Armyworms feed in large groups and their feeding has been described as “ground moving” in lawns. They feed during cooler times of the day (morning and evening) and they roll up and rest under the vegetative canopy (in the thatch layer in turf and in the base of leaves in vegetables) during the heat of the day.
Armyworms are difficult to control because of their spontaneity. However, in the lawn they hide in the thatch during the heat of the day. Over watering and fertilization can increase the amount of thatch. It is important to follow UF/IFAS guidelines for home lawn management. A good weed control program can also help to deter armyworms, because weeds serve as an alternate food source.
Numerous chemical control options are available, but softer chemicals such as horticultural oils and insecticides containing the bacteria Bacillus thuringiensis are recommended as a first line of defense. Insecticides should be applied in the morning or evening during feeding time. For additional control strategies and basic information please visit the UF/IFAS Armyworm Publication Page.
Armyworm feeding on a young corn plant. Credit: University of Illinois
by Sheila Dunning | Sep 16, 2015
“We have replaced this grass several times over the past few years; and it’s dying again.” I have heard this complaint too many times this summer. Last summer’s heavy rain, the stress of January’s icy weather, and this year’s extended summer have contributed to widespread outbreaks of Take-All Root Rot, a soil-inhabiting fungus Gaeumannomyces graminis var. graminis.
Symptoms of Take-All-Root-Rot. Photo credit: Sheila Dunning, UF/IFAS.
This disease causes yellow grass patches ranging in diameter from a few inches to more than 15 feet. The symptoms first appear in the spring, but the 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.
Since 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; the disease has been there potentially for years. If the turfgrass is not stressed, leaf symptoms may never be observed.
This disease is very difficult to control once the aboveground symptoms are observed. Measures that prevent or alleviate stress are the best methods for controlling the disease. Any stress (environmental or manmade) 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
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.
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.
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.
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 their 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 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-Root-Rot 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. However, 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.
With all the stresses that our lawns have experienced, it is very important to continue monitoring the turf and be cautious about the cultural practices being used. Take-All Root Rot is likely to flourish. Do not encourage its development. A pathology test with the University of Florida Laboratory can confirm the presence of the disease causing organism. Before resodding again, have the dying sod tested.
For information and the submission form go to:
Sample Submission Guide
For more information on the disease go to:
Take-All-Root-Rot
by Carrie Stevenson | Jul 27, 2015
Late summer brings hot, humid temperatures, and many Floridians are retreating from the heat into their air-conditioned homes. Unfortunately, those comforts of home also come with a price tag. When people think about energy efficiency, practices like turning off lights, purchasing energy-efficient appliances, good insulation and windows, and managing A/C temperature settings are the first things that come to mind. These are very important steps to take, not only to save money but also to conserve energy. The US Department of Energy has an excellent publication that can take you step-by-step through a home evaluation, and many energy companies offer a similar walk-through energy audit for free.
However, there are many best management practices that can be done outdoors to offset expensive home power bills. Planting trees is one example. Department of Energy studies have shown that when compared to a home in full sun, a shaded home may experience up to a 25% decrease in energy for cooling.
This home uses passive cooling from a front porch and numerous shade trees. Photo credit: Carrie Stevenson
Trees planted to shade eastern and western facing walls of your home can be the most effective, as these areas receive direct sun in the morning and afternoon. By preventing heat from entering your home, you prevent straining an air conditioning system that would otherwise have to counteract that heat. It is also helpful to provide shade over an air conditioning unit. Deciduous trees are ideal, as they have leaves to provide shade in the summer but drop them by winter, when you might want sunlight to passively heat your home.
In addition to shade, transpiration—the process of plants emitting moisture as they release water from leaf pores—creates cool spaces around vegetation. Grasses and shrubs along the edges of a home, or vines on nearby trellises, can cool walls and windows in this manner.
Finally, consider sprinkler systems. A home irrigation system can use a significant amount of energy to pump water throughout your yard. Calibrating your system and even reducing run time or frequency can also conserve water and reduce water bills.
For more information on energy-efficient landscaping, please visit www.myfloridahomeenergy.com or contact your local Extension office.
by Beth Bolles | Jul 20, 2015
Native plants can more readily be found in local nurseries to enhance landscape plantings. Not all natives are suited to every habit so it is still important to match the plant’s requirements with a suitable area in the landscape.
One low maintenance native that is more suited to a specific area is the landscape is the Gamma or Fakahatchee grass (Tripsacum dactyloides and T. floridana). This clumping perennial grass grows best in moist or even boggy soils. It has attractive green foliage and upright flower stems that appear in mid summer. Although the flowers are not very significant, they do have a red color when viewed up close.
The Eastern gamma grass can grow five feet in height so many gardeners prefer the dwarf version that reaches about 2-3 feet in height. Plant in areas of full sun or partial shade as a specimen plant or use in a mass of three or five.
In areas that receive colder temperatures, gamma grass can add fall interest to the garden. Leaves will change to a shade of red with first frost and plants can die back to the ground during freezing winters. New growth returns in the spring. Basic maintenance includes pruning back in the spring.
by Sheila Dunning | Jul 7, 2015
There are more than 100 species of plants and animals living in Florida that are in danger of extinction. These trees, flowers, reptiles, amphibians, birds, fish, mammals and invertebrates are listed as either threatened, endangered or species of special concern. As stewards of the land we must question, “What could the loss of a torreya tree, a lupine, a salamander, a butterfly, a woodstork, a right whale, a manatee, a sea turtle or a black bear do to our environment and our quality of life?”
Biological diversity is the variety and variability of species present in an ecosystem including the complex interactions of the many species. Regardless of their size or apparent significance, each species has a role in the circle of life and the food web. Preservation of all species is important. No one knows which ones hold the answers to the future of human existence on this planet.
Many significant developments in medicine have come from obscure plant and animal species. Modern day research includes a vaccine against leprosy being developed because of the nine-banded armadillo and horseshoe crabs being used in developing laboratory tests and finding remedies for several bacterial diseases. In agriculture, genes from wild species may provide the resistance for plant diseases, insects or even weather extremes that could save us from crop failure or possible starvation. There is an interdependence among living things. The extinction of one species may have a domino-like effect on other species. Stability of an ecosystem depends on bio-diversity.
To protect our future and the future of wildlife, the Endangered Species Act became federal law in 1976. This act is intended to protect and promote recovery of plants and animals that are in danger of becoming extinct as a result of human activity. The Environmental Protection Agency is responsible for ensuring the endangered species are protected from pesticides.
Pesticides can kill endangered plants and animals directly or indirectly. Birds mistaking them for food may eat granules, baits or treated seeds. Water contaminated with pesticides ranging in concentrations of less than 0.1 to 1.0 parts per million (ppm) can kill fish. Animals that eat treated crops, drink or wade in contaminated water or feed on tainted prey can be killed indirectly. Some pesticides can build up to lethal levels as predators consume multiple poisoned prey species.
There are certain things you can do to lessen the harmful effects of pesticides on fish and wildlife. Read all pesticide labels carefully to find out whether the use of the product requires special steps to protect endangered species. Determine if the site is designated as the current habitat of an endangered species. Find out this information by visiting http://www.epa.gov/espp/ and http://myfwc.com. When you have a choice of pesticides to use, choose one that is less or non-toxic to fish and wildlife. Read and follow the “Environmental Hazards” section and use the special precautions and measures to minimize harmful effects. Treat only the areas that need to be treated. Leave a buffer zone (untreated area) between bodies of water and treated areas. It is your legal and moral responsibility to protect endangered species by careful use of pesticides in and around their key habitat areas.
Information for this article was derived from University of Florida publications “Pesticide Effects on Nontarget Organisms” by Frederick Fishel and “Applying Pesticides Correctly” by Thomas Dean and Norman Nesheim.
