by Matt Lollar | Mar 24, 2022
Written by: Donna Arnold, University of Florida/IFAS Extension – Gadsden County
Have you ever noticed mounds of dirt popping up on your lawn, in your cattle pastures, and other places? You just might be experiencing an ant invasion. The Red Imported Fire Ant, (referred to hereafter as RIFA) came from South America in the early 1900s through the port of Mobile, Alabama. Today, they have spread across the US and have become a serious pest causing significant social, environmental, and economic impacts. RIFA mounds can be seen in well-manicured landscapes, but also can nest around tree roots and stumps, as well as under pavement, buildings, and indoor areas. Although RIFA do prey on flea larvae, chinch bugs, cockroach eggs, ticks and other pests, however the problems they create usually outweigh their benefits.
Lifecycle/description.
Red Imported Fire Ant. Photo Credit: University of Florida/IFAS
Size determines the lifespan of RIFA workers. Minor workers may live 30 to 60 days, media workers 60 to 90 days, major workers 90 to 180 days, and queens may live two to six years. Complete lifecycle from egg to adult takes between 22 and 38 days. RIFA are 1/8” to 1/4” long and reddish-brown or black in color.
RIFA usually respond rapidly and aggressively when disturbed. They clamp onto their victims with powerful jaws and sting repeatedly while injecting painful venom. The stings cause a burning sensation and itching blisters that can become infected. Although very uncommon, in severe cases, the stings can produce shock or cause death.
Where one can find RIFA
Winged alates preparing for nuptial flight. Photo Credit: Donna Arnold, University of Florida/IFAS Extension – Gadsden County
RIFA frequently invade home lawns, school yards, athletic fields, golf courses, parks, and other recreational areas. Additionally, electrical equipment and utility housing, home gardens, compost piles, mulched flowerbeds, pavement cracks, and the perimeter of bodies of water must all be considered when choosing a method of control.
Management
Two approaches can be taken to effectively manage RIFA.
- Single mound treatments
- Area-wide broadcast applications
Six methods of single mound treatment are available.
Mound Drenches. Large volumes of liquid toxic to ants are poured over a mound. Liquids can range from using several gallons of hot water to insecticides mixed with several gallons of water. This method may not reach the queen, therefore, not preventing colony elimination.
Surface Dusts. Similar to mound drenches, a dust or granular insecticide is applied over the top of the mound and then watered into the soil.
Mound Injections. The use of insecticides that may be pressurized and injected into a mound. Often this method is more expensive, but more effective, than mound drenches; however, more time may be required for this method.
Baits. Baits can be used for both individual mound and broadcast applications. A small amount of the bait is sprinkled around the mound and the ants then forage and bring the bait back to the colony to feed on. This method is slower acting, but more effective than drenching, dusting, or fumigating a mound because the workers will feed the bait to the queen and brood, thus gaining effective control of the colony.
Mechanical Control. Certain mechanical and electrical devices are on the market for controlling fire ants, but the efficacy has not been documented.
Home Remedies. Many homeowners will choose to pour boiling water or ignite flammable liquids over a mound. While these methods may bring about control, they are not recommended because they are both very dangerous, not only to humans, but also to the environment. Several other myths often circulate by the media or by way of word of mouth, often times these methods are anecdotal.
Area-wide broadcast applications
Currently, there are only a few products available for broadcast treatment of large areas. These products are either granular insecticides or baits composed of soybean oil and toxicant on a corn grit carrier. These granules are broadcast over a large area and are carried to the colony and fed to nestmates and the queen. This is a very effective application but does present problems because (1) ants may not find it, (2) do not feed upon the bait, and (3) some baits are light sensitive (as with hydramethylnon) and may inactivate before discovery by the ants. Reinfestation of any treated area, whether by broadcast treatment or individual mound treatment may occur.
As a result, other methods such as Biological Control is widely used to mitigate control of the RIFA.
Supporting information for this article can be found in the UF/IFAS EDIS publications (Managing Imported Fire Ants in Urban Areas) visit https://edis.ifas.ufl.edu/publication/lh059 and Red Imported Fire Ant, Solenopsis Invicta Buren (Insecta: Hymenoptera: Formicidae: Myrmicinae) https://edis.ifas.ufl.edu/publication/IN352.
by Joshua Criss | Mar 18, 2022
A Problem of Anticipation
The feeling is palpable, everyone is ready for spring. Can you hear them? The seeds beckoning in their packets, begging you to bury them in the soil. Every gardener struggles with this dilemma in early spring, but this year will surely be different. Maybe just maybe I can get my garden planted and watch with bated breath as life peeks its tiny shoots through the soil. Inevitably, harsh reality will set in with the realization that there will be a freeze dowsing your dreams before they take root.
Trying as that may be there is a respite. A small group of plants has heard your concerns. They provide the early spring color we so desperately seek in our landscapes. The trees and shrubs have answered your cries reaching out in the most beautiful way they know how. The saucer magnolias (Magnolia x soulangeana) have given us their teacup flowers all purple and perfect. The azaleas (Rhododendron spp.) are in full swing with all their magnificence shining bright. There is one tree that stands above them all in Florida landscapes. This month you’ll begin to see a tree that is the ultimate harbinger of springtime. A tree so native in the Panhandle that it bears the state’s name within its own. The tree I am speaking of is the Flowering Dogwood (Cornus florida).
Dogwood flower and bracts in bloom. Photo Credit Jim Stasz, USDA
A Tree Described
Florida in this instance derives from the Spanish florido meaning “full of flowers”. This tree will not disappoint on this front. A very common home landscape feature, it performs well in zones 5-9A. Growing between 20-30 feet in height with the spread to match, they may be pruned to a single trunk or allowed to grow in multiples to fit the landscape. This tree is known for early spring color, and thrives in sun of shade. Sometime between March and May, a splash of white or pink (sometimes red, cultivar dependent) lasting several weeks will rear up amid your winter scenery.
The showiness of this plant is not a flower, but a protective leaf structure known as a bract. The true flowers are small yellow to green clusters in the center of these bracts. Depending on the site conditions, the foliage turns maroon and the flowers to red berries in the autumn. The spring flowers, and later berries are a useful food source for pollinators and local birds respectively.
Dogwood trees in the wild. Photo Credit Smithsonian Institution
More Information
Flowering Dogwoods is a valuable addition to any gardener’s plot and fits right into a Florida Friendly Landscape. For more information on these trees, see this Ask IFAS document, or contact your local extension agent for additional information on this and any topic regarding your gardens and more.
by Molly Jameson | Mar 18, 2022
Variegated shell ginger is a good choice for adding color to shaded areas of the landscape. Photo by David W. Marshall.
What to Do in the Garden in March and April
Written by David W. Marshall, UF/IFAS Leon County Extension Agent Emeritus
Except for a couple of freezes, it has been a relatively mild winter. But those freezes were cold enough and long enough to kill many tropical plants almost to the ground. Will we have more freezes? It’s possible, though after we reach mid-March, the probability drops significantly.
Some plants, such as this firebush, had stems killed back to the ground by the cold and will re-sprout from the root system. Photo by David W. Marshall.
So, when can you start cleaning up all the cold damaged plants? You probably have the urge to do it as soon as possible, as the brown foliage and stems are a little depressing. Many of us have lots of cold-damaged plants and we want to get the cleanup finished. First, though, examine the plants to determine the extent of the cold damage. Scrape the bark with your fingernail or use a pocketknife to see if the tissue beneath is still green or if it has turned brown due to cold damage. In many cases, you will find that the stems have been killed back to within a foot of the ground. On other plants, you may find that some of the stems still appear green higher up and you may not have to cut them back quite as far. If that’s the case, you may wish to wait until mid-March to cut these plants back. In case we have another hard freeze, the damaged growth may offer a little insulation to the undamaged parts of the plant. With most plants there’s no real need to cut them back until the new growth starts popping out, probably in late March.
The stems of butterfly gingers can be completely removed now. Many of these will just pop off when pulled lightly. Others may have to be cut, but it won’t hurt them. Variegated shell gingers, in many cases, will still have some undamaged growth mixed in below the brown leaves. You won’t kill a well-established shell ginger by cutting it back now, but because of the insulating effect of the brown leaves, it’s probably best to wait until mid-March to cut them back.
Azaleas and camellias, typical of a North Florida spring, were blooming by late February this year. If you don’t have some of these in your yard, now is a good time to plant. Photo by David W. Marshall.
You may have other shrubs that you wish to prune now also. Wait to prune spring bloomers like loropetalum and azalea until after they finish flowering. Some overgrown shrubs may need to be cut back hard to rejuvenate them, and if you do it now, they will have longer to recover. Before crepe myrtles start putting out new leaves, work on the shape of the tree. Remove poorly placed rubbing and crossover branches by cutting all the way back to the trunk or branch from where they grow. Don’t, however, top the tree unless you are purposely trying to pollard the tree and completely understand how to do it correctly. Otherwise, you will likely end up with a mess.
In mid-March, be prepared to plant warm-season vegetables such as tomatoes, snap beans, pole beans, lima beans, sweet corn, southern peas, squash, and watermelons. So, make sure you have the garden tilled before then. If you wait until April or May to plant, your harvest will be later and the insect and diseases will get much of the crop. Warm-season herbs can be added after mid-March.
Don’t be overly anxious to fertilize your lawn, especially if you have centipede grass. Wait until at least mid-March. Make sure the lawn has been fully green for three weeks before fertilizing. If this pushes you into April, fine. It’s better to fertilize too late than too early. Centipede lawns that are fertilized too early often have spring yellowing problems. St. Augustine grass is more forgiving, but don’t fertilize it either until at least mid-March. Use 6.7 pounds of 15-0-15 fertilizer per 1,000 square feet of lawn area. If the fertilizer doesn’t contain at least a third of its nitrogen in a slow-release form, though, cut the application rate in half.
Most of the weeds in the lawn now are winter annuals that will die out as the weather gets hotter. Just keep your lawn mowed regularly until they do. If you usually still have problems with weeds in the summer, though, you could use a pre-emergent herbicide to reduce the emergence of the summer weeds.
To keep fire ants out of your yard, broadcast a bait formulated product over the entire yard, according to the label directions. Plan to treat again in fall. You can quickly apply the bait using a small hand spreader available from your garden center.
Now, before it gets hotter, add some colorful camellias to your landscape. Photo by David W. Marshall.
Now, before it gets hotter, add some colorful azaleas, camellias, roses, and loropetalum shrubs to your landscape. Also consider fragrant plants such as tea olives, banana shrubs, and sweet viburnum. The sooner you plant these in the spring, the quicker they will get established and grow.
Lavender trumpet vine (Clytostoma callistegioides), crossvine (Bignonia capreolata), coral honeysuckle, and Confederate jasmine are vines that flower during this period of the year. Now is a good time to plant them also.
Don’t forget groundcovers such as liriope, Lomandra, Mondo grass, Dianella (New Zealand flax), African iris, or any of a variety of ferns. Groundcovers planted now will have a full growing season to get established. Groundcovers are often a good choice for plantings in front of the house where you don’t want tall shrubs.
Add some long-blooming seasonal color to your yard this spring. Once we reach mid-March the nurseries will be loaded with many possibilities. Petunias will give you a lot of color in sunny areas for about three months. After the summer rains start in June they normally decline. Pentas will hold up on through the summer and into fall. They prefer full sun but will take a little filtered sunlight too. Sunpatiens® will work in sun or shade and should hold up through the summer. Melampodium will give continuous yellow blooms in sunny areas through summer and into fall. Torenias, especially the trailing or vining types, are excellent for providing low-growing color in areas that receive morning sun but not so much harsh afternoon sun. But there are many other options, too, so visit a full-service nursery with knowledgeable employees that can guide you.
Pentas can be planted in mid to late March and will give color until late fall. Plant in full sun to light shade. Photo by David W. Marshall.
Also, later in the month, start planting perennials such as firebush, angel’s trumpet, cigar flower, and Turk’s cap so you will have color later in the season that will last into fall. These perennials will return each year, even if the tops get frozen back.
There’s no need to fertilize mature trees and shrubs that are growing well. But young plants which you’re trying to encourage to grow will benefit from an application of fertilizer now. The same 15-0-15 that you used for the lawn can be used on trees and shrubs, provided it’s not a weed-and-feed product with an herbicide. The exception would be with palms, especially if you’ve noticed that your palms haven’t been looking that healthy. Use an 8-2-12 or similar palm fertilizer that has four percent magnesium and micronutrients also. If you have a lot of palms in the lawn, just use this palm fertilizer on your whole lawn.
If you didn’t get around to fertilizing fruit plants in February, do it now. After mid-March is also a good time to plant new citrus trees such as satsuma, orange, or grapefruit. You have a full growing season ahead!
Anything that you plant now will need regular watering. That’s what they were receiving in the nursery. Remember that for several months, at least, all the roots will still be in the root ball that was in the pot, even after you put the plant in the ground. So, soak this root ball at least every other day. Don’t rely on a sprinkler system that only comes on once or twice a week. That’s not enough water for the limited root systems of new plants.
Written by David W. Marshall, an Extension Agent Emeritus with UF/IFAS Extension Leon County.
by Beth Bolles | Mar 10, 2022
Several years ago the Escambia County Master Gardener Volunteers added a Leopard plant, Farfugium japonicum to the office demonstration gardens. This was a new plant for me and I was immediately impressed with look and performance of this plant in a filtered shade garden.
Leopard plant’s attractive leaves and flowers make it an accent in the shade garden. Photo by Beth Bolles, UF IFAS Extension Escambia County.
Although not native to the United States, Leopard plant make an interesting addition to the Florida garden. The large green leaves can provide a tropical look throughout the entire year since it is hardy in growing zones 7-10. An added bonus of the Leopard plant are spikes of bright yellow flowers in the fall and winter months. When you use Leopard plant as a mass planting, it certainly becomes the focus in our cooler months.
Leopard plant on display in Downtown Pensacola. Photo by Beth Bolles, UF IFAS Extension Escambia County.
There are many cultivars of Leopard plant and the selections with white (‘Argenteum’) or yellow (‘Aureomaculatum’) patterns on the leaves give the plant it’s common name. There are also cultivars with curled or crinkled leaves. All plants will thrive in partial shade with some additional water when rainfall is lacking. The clumps will continue to enlarge so you can often share a piece with a friend after a few years.
by Carrie Stevenson | Mar 10, 2022
Twigs dangle from a branch, held in place by horsehair fungus rhizospheres. Photo credit: Carrie Stevenson, UF IFAS Extension
Imagine walking through the woods, enjoying the fresh air and birdsong, when you notice a twig just dangling midair. On first glance, you might presume it is stuck in a vine or a large spider web. However, this material is thinner than a vine and there are no spiders or webs to be found. On closer inspection, you see the twig is entangled in a dark knot of string, slightly thicker than a human hair. Following the source of the black string leads to a lacy network of the same material, flat against and around the branch from which the twig hangs. Fifteen feet down the trail, you come across the same thing—more twigs hanging from “string” in the trees, dangling from a knot of thin black material. What is going on here?
After some research, my conclusion is that we have come across horsehair fungus (Mirasmius spp). Mushrooms and other fungi have long, thin, rootlike structures called rhizomorphs. Rhizomorphs are composed of large numbers of microscopic hyphae, which are tubular and exchange nutrients and water among other parts of the fungus. The hyphae are typically located underground, but in this instance, they are visible in the open.
The ropy network of rhizospheres is visible on the branch, then turns into thin fibers that can trap plant debris. Sample provided by Suzy Marshall.
Aerial rhizomorphs are an excellent example of an evolutionary strategy known as resource partitioning. By forming a netted trap to intercept falling leaf material on a tree, the fungus gets a jumpstart on the decomposition process, taking nutrients from dying plant material before it falls to the ground. The tree-dwelling fungus is thus not competing directly with fungi on the ground, and both types of fungi can thrive. In human terms, this is loosely analogous to co-workers labeling their own food in a shared refrigerator. Everyone eats, but no one has to compete with another for nutrition.
A bird’s nest in Argentina is composed primarily of strong horsehair fungus fibers. Photo credit: Danny Newman
The common name, “horsehair fungi” applies to many species around the world. They are most common in nutrient-poor subtropical and tropical forests, where any available nutrients in the soil are used up quickly by the lush tree growth. They can be found here along the Gulf Coast, up to the Appalachian Mountains, and as far away as equatorial rainforests. In a Malaysian study, researchers found that the aerial fungi trapped up to 225 pounds of fallen plant material per acre! This network of material also supported a significant population of arthropods, which were crucial parts of the overall ecosystem by providing pollination, herbivory, and serving as detritivores. One study of spruce-fir forests in the northeastern United States showed that birds are known to use the material as a nest lining, as it is lightweight but very sturdy. In this particular research, 85% of the nests (particularly of warblers and thrushes) examined utilized the material.
