by Mark Tancig | Dec 16, 2020
Many folks are giddily decorating their homes for the holiday season. For some outdoor enthusiasts and/or environmental educators, now is the time to collect and preserve a natural decoration, with care. Hornet nests offer a large natural ornament that can be used as a conversation piece or to teach people about an interesting native wasp that is often feared.
The face of a baldfaced hornet! Credit: Piccolo Namek, Wikimedia Commons.
The bald-faced hornet (Dolichovespula maculata) is a type of wasp closely related to yellowjackets, of which there are two species that are known from Florida, the eastern yellow-jacket (Vespula maculifrons) and southern yellowjacket (Vespula squamosa). The bald-faced hornet is different than its yellowjacket relatives in that it creates a large aerial nest rather than a subterranean nest. If you have seen a hornet’s nest in person, you know how impressive they can be. Surprisingly, they can be safely preserved for indoor display!
Hornet colonies begin each spring and are “founded” by a lone adult queen that made it through the winter, hiding under the bark of logs and such. The lone queen begins creating the papery brood cells and laying eggs. Once those eggs begin to hatch, the newly hatched all-female crew of hornets begin assisting in nest building and foraging while the queen shifts to only laying eggs. Towards the end of fall, some of the eggs receive more food (they become queens) and the queen also begins to lay male eggs. Once these emerge, they mate, and the cycle starts all over again, with the colony dying back, leaving an abandoned and impressive aerial nest behind.
The aerial nest of the baldfaced hornet. Credit: Preston Robertson, Florida Wildlife Federation.
To collect that impressive nest safely, wait until a couple of freezes have passed. At this point, most, if not all, of the hornets will have perished and that lone queen will be sheltering through the winter. Don’t wait too long since these nests are utilized by other wildlife and may be destroyed or get beaten up by the weather. Simply cut the nest off its support (realize it may be heavy). To be extra sure you don’t bring live hornets inside, you can leave the nest in a protected outdoor location, such as a garden shed or the garage, where it will be exposed to further cold temperatures. This also allows any “off” smells from rotting larvae to air out. Don’t worry about harming these larvae as they would starve either way since they must be fed by adult hornets! There is no need to use varnishes or polyurethanes for preservation as the nest will keep indefinitely as long as kept in a dry environment free from a lot of handling or vibrations.
Bingo, you now have a natural ornament that can last through many seasons and provide for learning opportunities and lots of conversation!
For more information on wasps, including hornets and yellowjackets, please see the Yellowjackets and Hornets EDIS document from UF/IFAS. Information from Iowa State University’s website Preserving and Displaying a Hornet’s Nest was also used to help write this article.
by Molly Jameson | Oct 28, 2020
The Carolina wolf spider (Hogna Corolinensis) is the largest wolf spider, measuring up to 22-35 mm. It is the state spider of South Carolina, the only state that recognizes a spider as a state symbol. Photo by Eugene E. Nelson, Bugwood.org.
Halloween coincides with a full moon this year, so you may want to be on the lookout for hungry werewolves. In your garden, you may also be on the lookout for a much smaller, yet just as frightful, type of wolf. Well – wolf spider, that is!
But have no fear, just as the little werewolves of the neighborhood will be sated by a handful of sweets, a wolf spider will be satisfied once it finds its meal of choice. Wolf spiders are predators, feeding primarily on insects and other spiders. Much like a werewolf, wolf spiders prefer to stalk their prey at night. This is good news for gardeners – as it means you’ll have an insect hunter working for you while you sleep.
Wolf spiders are in the family Lycosidae, and there are over 2,000 species within this family. Lycos means “wolf” in Greek, inspired by the way wolves stalk their prey. Although, unlike wolves who hunt in packs, wolf spiders are very much solitary. These spiders do not spin webs; instead, they keep to the ground, where they can blend in with leaf litter on the soil floor. Some wolf spiders even dig tunnels, or use tunnels dug by other animals, to hide and hunt.
Although most spiders have poor eyesight, wolf spiders have excellent vision, which they use to spot prey. Photo by James O. Howell, University of Georgia, Bugwood.org.
Wolf spiders have eight eyes that are arranged in three rows. This includes four small eyes in the lowest row, two very large eyes in the middle, and two medium-sized eyes off to either side on top. Some of their eyes even have reflective lenses that seem to sparkle in the moonlight. Using their excellent eyesight and sensitivity to vibrations, they stealthily stalk prey such as ants, grasshoppers, crickets, and other spider species. Female wolf spiders, which are bigger than males, may even take down the occasional lizard or frog.
No matter the meal, many wolf spiders pounce on their prey, hold it between their eight legs, and roll with it onto their backs, creating a trap. They then sink their powerful fangs, which are normally retracted inside the jaw, into the victim. The fangs have a small hole and hollow duct, which allows venom from a specialized gland to pass through during the bite. This venom quickly kills the prey, allowing the wolf spider to eat in peace.
Although wolf spiders could bite a person if threatened, they prefer to run away, and their venom is not very toxic to humans. If you do get bitten, you may have some swelling and redness, but no life-threatening symptoms have been reported. Werewolves on the other hand? For these, you’re on your own!
by Pat Williams | Oct 21, 2020
Normally, you will have one of four answers: “yes”, “no”, “I don’t know” or “what are super bugs?” The answer to the last one is an insect or other pest that has become resistant to chemical treatments through either natural selection (genetics) or an adaptive behavioral trait.
The next question is do you treat insect or pest problems at home with a purchased EPA registered chemical (one purchased from the nursery or other retailer)? If you answered yes, then the next question is how many times in a row do you apply the same chemical? If you only use one chemical until the product is used up, then you might be creating super bugs. Do you ever alternate chemicals and if you answer yes, do you understand chemical Modes of Action (how the pesticide kills the pest)? If you do not, then chances are the rotating chemicals might act in the same way. Thus, you are creating super bugs because in essence you are applying the same chemical with different labels.
Click on image for a larger view. Taken from https://edis.ifas.ufl.edu/in714.
One of the first ways to reduce creating super bugs is to practice Integrated Pest Management (IPM). The very last step of an IPM philosophy is chemical control. You should choose the least toxic (chemical strength is categorized by signal words on the label: caution, warning, and danger) and most selective product. A chemical label advertising it kills many pests is an example of a non-selective chemical. You want to choose a chemical that kills your pest or only a few others. In Extension education, you will always hear the phrase “The label is the law.” To correctly purchase a chemical, you must first correctly identify the pest and secondly the plant you want to treat. If you need help from Extension for either of these, please contact us. Before purchasing the chemical, always read the whole label. You can find the label information online in larger print versus reading the small print on the container.
IRAC phone app.
You now have the correct chemical to treat your pest. Wear the recommended personal protective equipment (PPE) and apply according to directions. If your situation is normal, the problem is not completely solved after one treatment. You might apply a second or third time and yet you still have a pest problem. The diagram explains why you still have pests or more accurately super bugs.
Now the last question is how do we really solve the problem given that chemicals are still the only treatment option? A bit more work will greatly help the situation. You need to download the Insecticide Resistance Action Committee (IRAC) guide and find the active ingredient on your chemical label (http://edis.ifas.ufl.edu/pi121 or https://irac-online.org/modes-of-action/ and select the pdf). If you are like me, you can just download the IRAC MoA smartphone app and type in the active ingredient; otherwise, Appendix 5 in the pdf has a quick reference guide. Either way, you will know the Group and/or Subgroup. A lot of commonly purchased residential chemicals fall within 1A, 1B or 3. The successful treatment option is to select chemicals from different group numbers and use them in rotation. If you start practicing this simple strategy, your treatment should be more successful. Then when someone asks if you are creating super bugs, your answer will be no.
If you have any questions about rotating your chemical Modes of Action, please contact me or your local county Extension agent. For more resources on this topic, please read Managing Insecticide and Miticide Resistance in Florida Landscapes by Dr. Nicole Benda and Dr. Adam Dale (https://edis.ifas.ufl.edu/in714).
by Daniel J. Leonard | Oct 14, 2020
Article by Jessica Griesheimer & Dr. Xavier Martini, UF/IFAS North Florida Research and Education Center, Quincy
Dioscorea bulbifera, commonly known as the air potato is an invasive species plaguing the southeastern United States. The air potato is a vine plant that grows upward by clinging to other native plants and trees. It propagates with underground tubers and aerial bulbils which fall to the ground and grow a new plant. The aerial bulbils can be spread by moving the plant, causing the bulbils to drop to the ground and tubers can be spread by moving soil where an air potato plant grew prior. The air potato is commonly confused with and mistaken as being Dioscorea alata, the winged yam which is also highly invasive. The plants look very similar at first glance but have subtle differences. Both plants exhibit a “heart”-shaped leaf connected to vines. The vines of the winged yam have easily felt ridges, while the air potato vines are smooth. They also differ in their aerial bulbil shapes, the winged yam has a long, cylinder-shaped bulbil while the air potato aerial bulbil has a rounded, “potato” shape (Fig. 1).
In its native range of Asia and Africa, the air potato has a local biocontrol agent, Lilioceris cheni commonly known as the Chinese air potato beetle (Fig. 2). As an adult, this beetle feeds on older leaves and deposits eggs on younger leaves for the larvae to later feed on. Once the larvae have grown and fed, they drop the ground where they pupate to later emerge as adults, continuing the cycle. The Chinese air potato beetle will not feed on the winged yam, as it is not its host plant.Current methods of air potato plant, bulbil, and tuber removal can be expensive and hard to maintain. The plant is typically sprayed with herbicide or is pulled from the ground, the aerial bulbils are picked from the plant before they drop, and the underground tubers are dug up. The herbicides can disrupt native vegetation, allowing for the air potato to spread further should it survive. If the underground tuber or aerial bulbils are not completely removed, the plant will grow back.
The Chinese air potato beetle is currently being evaluated as a potential integrated pest management (IPM) organism to help mitigate the invasive air potato. The beetle feeds and reproduces solely on the air potato plant, making it a great IPM organism choice. During 2019, we studied the Chinese air potato beetle and its ability to find the air potato plant. It was found the beetles may be using olfactory cues to find the host plant. Further research is conducted at the NFREC to increase natural aggregation of the beetles on air potato to improve biological control of the weed.
Chinese Air Potato Leaf Beetle.
If you have the air potato plant, or suspect you have the air potato plant, contact your local UF/IFAS Extension Agents for help!
by Evan Anderson | Oct 14, 2020
A newly hatched armyworm –photo by Lyle Buss
With a population that never seems to quite disappear in North Florida, the armyworm is a caterpillar pest of many plants. There are four types found in our area: fall, southern, yellow-striped, and beet armyworms. The caterpillars pupate into moths, which breed roughly from April to December, but warmer weather may lead to them being sighted even in the middle of winter. Adult moths, which are relatively nondescript and gray-brown in appearance, lay masses of 100-200 eggs on plants. Young armyworms are tiny and very difficult to detect, often hiding during the brightest parts of the day.
A fall armyworm. –photo by J L Castner
The armyworm grows to a length of about 1 ¼ inches, taking about two weeks to reach its full size. The caterpillar builds a cocoon in the soil and pupates into a moth, living another one to three weeks. With its ability to eat a broad range of plants, this can lead to large populations of these insects in a relatively short time.
Armyworms seem to prefer eating grasses (especially Bermudagrass in lawns), but will chew on almost anything in their path. They have been observed eating citrus trees, tobacco, cotton, strawberries, and even weeds like pigweed and nutsedge. A hungry armyworm might even turn on its fellow caterpillars, eating them as well if they are too close. When large numbers of these pests are present, the damage they do to surrounding foliage can be stark. Young caterpillars may skeletonize leaves, while older larvae will make holes in leaves or defoliate plants fully.
Years with an abundance of wet or humid weather seem to help armyworms reproduce. Armyworms seem to be attracted to newly established turf, and heavy fertilization of turfgrass in late summer can also cause populations to build. Scout for them
A beet armyworm. –photo by Serena Robison
during cooler hours of the day, or when it is overcast or rainy. Mixing a tablespoon of dishwashing soap in a gallon of water and pouring it over a four-square foot area will cause insects to crawl to the surface – do this if damage is present and armyworms are suspected. For lawns, treatment at the first sight of damage may help, though a lawn may very well survive an attack by armyworms. If chemical control is necessary, there are numerous options. Products containing the active ingredients Bacillus thuringiensis, acephate, bifenthrin, carbaryl, permethrin, spinosad, and others have all been labeled for use on armyworms.
For more information, see our EDIS publication on fall armyworm at https://edis.ifas.ufl.edu/in255 or contact your local Extension office.
by Larry Williams | Oct 1, 2020
Adult cicada on tree branch, Photo credit: Lyle Buss, UF Entomologist
“What is that noise,” asked the visitors to Middle Georgia when I was a teenager. They were visiting during the summer from El Paso, Texas. I asked, “What noise?” The reply, “That loud noise in the trees.” I responded, “Oh, those are cicadas.’ There are sounds that are so common that sometimes you quit hearing them.
Before the visitors left for El Paso, I made sure to show them the brown, dry shells (exoskeletons) of cicadas that are not difficult to find attached to the trunk of a Georgia pine tree during summer. Cicadas leave their nymph exoskeletons on the trunks of trees and sometimes shrubs when they shed them to become mature flying adults.
You may not have ever seen a cicada but you’ve undoubtedly heard one if you live in Florida. These insects make a loud buzzing noise during the day in the spring and summer. Male cicadas produce their distinctive calls with drum-like structures called timbals, located on the sides of their abdomens. The sound is mainly a calling song to attract females for mating.
Cicadas spend most of their life underground as nymphs (immature insects) feeding on the sap of roots, including trees, grasses as well as other woody plants. They can live 10 or more years underground as nymphs. In some parts of the United States, there will be news reports of when periodical cicadas are expected to emerge from the ground. Periodical cicada species mature into adults in the same year, usually on 13- or 17-year life cycles. Their numbers can be enormous as they emerge, gaining much local attention. However, cicada species in Florida emerge every year from late spring through fall and in much smaller numbers as compared to the periodical cicadas.
Cicada emerging from exoskeleton, Photo credit: Lyle Buss, UF Entomologist
There are at least nineteen species of cicadas in Florida, ranging from less than a ¼ inch to over 2 inches in length. Some people might be frightened by their size and sounds but thankfully cicadas don’t sting or bite. They are a food source for wildlife, including some bird species and mammals.
Very rarely, I’ll have someone ask about small twigs from trees found on the ground as a result of the female cicada’s egg-laying process. But because this is usually such a minor issue with practically no permanent damage to any tree, cicadas really aren’t considered to be a pest of any significance in Florida.
For more information on cicadas, contact the University of Florida Extension Office in your County. Or visit the following UF/IFAS web page. https://edis.ifas.ufl.edu/in602
