by Larry Williams | May 11, 2017
Adult Ladybug. Photo Credit: James Castner University of Florida
A number of summers ago, I noticed whiteflies on a confederate rose plant in my landscape. I considered using an insecticide to control the whiteflies but decided against doing so after taking a closer look. What I found was a population of ladybugs – eggs, larvae, pupae and adults.
Ladybug adults and larvae eat whiteflies, as well as other soft-bodied insects such as aphids. So, I waited to see what would happen.
At first I was seeing mostly adult whiteflies, which look like tiny white moths. Adult whiteflies mate and then lay eggs on the underside of leaves. The eggs hatch into flat translucent scale-like nymphs that suck the “juice” from the underside of the leaves.
Eventually, some of the leaves developed a black coating called sooty mold. As certain insects (primarily aphids, some scales and whiteflies) feed, they excrete plant sap that coats the leaves. Sooty mold then grows on this sugary sap. It’s not a pathogen. It just makes the leaves look ugly.
Knowing that the whiteflies would not kill the confederate rose, I was willing to tolerate the sooty mold and allow the ladybug population to build.
Allowing whiteflies to live on your plants may not always be the best option. But in order to have beneficial insects in your landscape, there must be some “bad” insects for them to eat.
Insects such as ladybugs, lacewings and praying mantises eat many pest insects. Encouraging these beneficial insects can allow you to reduce the amount of pesticides applied.
It’s important to learn to recognize the adult and immature stages of these beneficial insects. Ladybugs have larvae that look nothing like
Ladybug larva. Photo credit: Aristizabal University of Florida
the adults. Some ladybug larvae look like small orange and black alligators. Others may resemble mealybugs. Many gardeners that would never kill adult ladybugs mistake their larvae as pests and kill them with insecticides.
The following UF/IFAS Extension website will help you learn to recognize many of our beneficial insects. http://edis.ifas.ufl.edu/topic_beneficial_insects
Once you find beneficial insects in your landscape, reduce or eliminate the use of insecticides. When an insecticide is needed, use environmentally friendly options such as insecticidal soaps, horticultural oils and products that contain Bacillus thuringiensis (Bt).
Sometimes a heavy stream of water from a water hose is all that is needed to remove pest insects from plants and reduce their numbers to an acceptable population.
Remember, leaving a few pest insects is a great way to attract beneficial insects. Tolerating a minor infestation and a little plant damage will benefit the helpful insects, your pocketbook and the environment.
by Carrie Stevenson | May 1, 2017
The Southeastern blueberry bee uses buzz pollination on a blueberry plant. Photo credit: Tyler Jones, UF IFAS.
This time of year, blueberry bushes are flowering and small fruit are coming onto the wild and cultivated bushes in north Florida. Many of us, myself included, look forward to the late-spring harvest of blueberries, taking our children out to u-pick operations and digging out family recipes for blueberry-filled desserts.
What many do not know, however, is that there’s a specialized bee that literally lives for this season. During the last few weeks, this little insect has been furiously pollinating blueberry bushes during its short, single-purpose lifetime.
The Southeastern blueberry bee, Habropoda labriosa is active only in mid-March to April when blueberry plants are in flower. They are smaller than bumblebees, and the yellow patches on their heads can differentiate males. Blueberry pollen is heavy and sticky, so it is not blown by the wind, and the flower anatomy is such that pollen from the male anther will not just fall onto the female stigma. Blueberry bees must instead attach themselves to the flower and rapidly vibrate their flight muscles, shaking the pollen out. Moving to the next flower, the bee’s vibrations will drop pollen from the first flower onto the next one. This phenomenon is called “sonicating” or ‘buzz pollination” and is the most effective method of creating a prolific blueberry crop.
Blueberry bees do not form hives, but create solitary nests in open, sunny, high ground. Females will dig a tunnel with a brood chamber large enough for one larva, filling it with nectar and pollen. After laying an egg, the female seals the chamber and the next generation is ready. The species produces only one generation of adults per year.
By the time we are picking fresh blueberries next month, you probably won’t see any blueberry bees around. However, we should all consider these insects’ short-lived but vitally important role in Florida’s $82 million/year blueberry industry!
For more information, check out the beautifully illustrated USDA Forest Service publication, “Bee Basics—An Introduction to our Native Bees,” or North Carolina State University’s entomology website.
by Sheila Dunning | Mar 20, 2017
Now is the time to prevent your azaleas from being attacked by lace bugs. The azalea lace bug, Stephanitis pyrioides, overwinters as eggs on the underside of infested leaves. Eggs hatch in late March and early April. The insect then passes through five nymphal instars before becoming an adult. It takes approximately one month for the insect to complete development from egg to adult and there are at least four generations per year. Valuable plants that are susceptible to lace bug damage should be inspected in the early spring for the presence of overwintering lace bug adults, eggs and newly hatched nymphs. Inspect these plants every two weeks during the growing season for developing lace bug infestations.
Both adults and nymphs have piercing-sucking mouthparts and remove sap as they feed from the underside of the leaf. Lace bug damage to the foliage detracts greatly from the plants’ beauty, reduces the plants’ ability to produce food, decreases plant vigor and causes the plant to be more susceptible to damage by other insects, diseases or unfavorable weather conditions. The azalea can become almost silver or bleached in appearance from the feeding lace bug damage.
However, lace bugs often go undetected until the infested plants show severe damage sometime into the summer. By then several generations of lace bugs have been weakening the plant. Inspecting early in the spring and simply washing them off the underside of the leaves can help to avoid damage later and the need for pesticides.
Adult lace bugs are flattened and rectangular in shape measuring 1/8 to 1/4 inch long. The area behind the head and the wing covers form a broadened, lace-like body covering. The wings are light amber to transparent in color. Lace bugs leave behind spiny black spots of frass (excrement).
Lace bug nymphs are flat and oval in shape with spines projecting from their bodies in all directions. A lace bug nymph goes through five growth stages (instars) before becoming an adult. At each stage the nymph sheds its skin (molts) and these old skins often remain attached to the lower surface of infested leaves.
Azalea lace bug eggs are football-shaped and are transparent to cream-colored. Lace bug eggs are found on the lower leaf surface, usually alongside or inserted into a leaf vein. Adult females secrete a varnish-like substance over the eggs that hardens into a scab-like protective covering.
For more information go to: http://entomology.ifas.ufl.edu/creatures/orn/shrubs/azalea_lace_bug.htm
by Les Harrison | Mar 11, 2017
It is an often made wish of summer that the cold weather of winter will kill all the mosquitoes, gnats and no-see-ums. This climactic fete would spare people, pets and livestock the irritation of encountering these low flying pest and their predatory behavior.
Unfortunately, the thermometer would have to drop to levels approaching the surface temperature of the planet Neptune to eliminate these winged annoyances.
There are individual steps which will help minimize the potential for exposure to exotic diseases.
Check surroundings for standing water, especially in secluded spots or small quantities. The home landscape and patio garden can produce hundreds, if not thousands, of hungry mosquitos during the summer if standing water is left for long.
Trays and dishes under flower pots commonly collect water which is usually left to evaporate or be absorbed by the plant over time. To mama mosquito this shallow and protected source is an ideal location to deposit eggs for the next generation of voracious airborne insects.
Plants with natural depressions or “cups” can accumulate enough irrigation and rain water to establish an effective mosquito nursery. Even though it may evaporate, these tiny pools will last long enough to hatch many mosquito larvae into potential disease vectors.
Back porch bromeliads can easily deliver this undesirable outcome. So too can mature live oak trees which commonly have hollow spaces between large branches.
Even a wheelbarrow left to the elements can serve as a portable pond to maternity minded mosquitos. Dumping the water on a frequent basis is the easiest method, but there are also larvae-cides which are effective in difficult to dump reservoirs.
Protective clothing when outdoors is useful to reduce exposed skin which mosquitos view as an excellent dining site. Heavier fabrics and loose-fitting designs provide the best protection while maintaining maximum comfort for the wearer.
Minimizing exposure at dusk and dawn, when native mosquitos are most active, will reduce the probability of serving as an unsuspecting blood meal for a swarm or lone hunter. Unfortunately, some of the exotic mosquitos are prowling 24 hours a day and are pleased to attack at any opportunity.
As the weather warms, be ready for mosquito season. This past winter only whetted their appetite.
by Sheila Dunning | Dec 7, 2016
Christmas is coming. So much to do. Picking out the perfect, fresh-cut tree is one of the important 
tasks. Every family member has their specific requirement. “It has to be a certain species.” It has to be a specific height and shape.” And, of course, “It has to smell great.” So, a decision is made. The perfect tree is toted home, put up and beautifully decorated. A week later, mom shrieks, “There’s ticks all over the living room!” Don’t panic. Upon inspection, you will discover that the bugs coming from your “perfect” Christmas tree are Cinara aphids.
Cinara are a group of several species of large brown or black aphids that feed on conifers including
all pines, spruces and firs. When the Christmas trees are cut at the farm and bundled for shipment, the aphids get trapped. With warmer temperatures indoors, the aphids become active. Infestations may also arise from overwintering eggs that hatch. As the tree dries out, the aphids crawl from the tree into the rest of the house.
No worries. Cinara aphids only feed on conifers, so they pose no threat to other plants. They are not a danger to people or pets either. But don’t get rid of them by smashing them. You may be left with a nasty purple stain to have to clean up. Instead, pull out the vacuum and suck them up.
So, if you are one of those people still shopping for the “perfect” tree, add a preemptive strike to your decorating procedure. Unbundle and shake, shake, shake that tree outside before bringing it in. Then the only shrieking going on will be when mom opens the fabulous present you gave her.
by Larry Williams | Oct 26, 2016
Saddleback Caterpillar – Image Credit Matthew Orwat
The reality of what happens deep down in the darkness of a fire ant mound hidden to human eyes or in the tunnels of a mole cricket where only creepy crawly things dare to enter may be too scary to believe.
University of Florida Institute of Food and Agricultural Sciences along with USDA introduced a tiny South American fly to the U.S. to help control the pesky imported fire ant. Literally, these introduced phorid flies cause the imported fire ants’ heads to fall off. They then use the decapitated heads to reproduce. The flies hover above the ants, dive in, latch on to the ant’s body and inject their eggs. The egg hatches, and a maggot wiggles its way into the ant’s head, where it grows for two to three weeks before secreting a chemical that dissolves the membranes holding the ant’s body together. In a few hours the ant’s head falls off. The maggot eats everything in it and then uses it as a pupae case. Gruesome, isn’t it?
Assassin bugs are frequently seen slowly crawling on shrubs in our landscapes. Most are brown to black but many are brightly colored. A common species is reddish-orange in the nymph stage. Assassin bugs feed on many harmful insects. Caterpillars are their favorite food.
They digest their prey before eating it. They do this by piercing their victim with their sharp beak, injecting digestive enzymes. This causes chaos on the unfortunate insect’s nervous system and liquefies the internal organs. The liquefied contents are then consumed, leaving only the shell of its kill. How tragic.
The larra wasp, an introduced predatory insect by University of Florida entomologists, enters a mole cricket tunnel. The female wasp will pounce on the mole cricket, wrestle with it and sting it on its soft underside. This immobilizes the mole cricket long enough to allow the wasp to deposit a single egg on its underside. The mole cricket recovers and burrows back into the ground. The wasp larva eventually hatches and slowly eats the mole cricket alive. Poor mole cricket.
We mere mortals should be aware of these horrifying happenings occurring in our own backyards. And we should be frightened by those people who attempt to kill every six-legged critter in sight because they have wrongly identified them as bad. In reality, less than one percent of all insects that exist are damaging to our plants. Most are of no consequence to our lawns, landscapes or gardens. And many are beneficial.
These beneficial insects are helping us gardeners battle the bad bugs during Halloween and year round.
