by Beth Bolles | Feb 27, 2020
Landscape activities have already begun in our Panhandle counties with cleanup, mulching, raking, and pruning. Our mild temperatures and days with sunshine spur us to jump into our landscape preparations for the spring growing season.
This year before you send all your debris to the compost pile or patch up thinning turf areas, consider that some landscape imperfections may actually be good for local wildlife.
We all know how important it is to plant nectar attracting plants for bees but there are other easy practices that can help promote more native bees in local landscapes. There are some solitary native bee pollinators that will raise young in hollow stems of plants. Instead of cutting all your old perennial or small fruit stems back to the ground, let some stay as a home to a native pollinating bee. This does not have to detract from the look of the landscape but can be on plants in the background of a border garden or even hidden within the regrowth of a multi stemmed plants. Plants that are especially attractive to native bees have a pithy or hollow stems such as blackberry, elderberry, and winged sumac.
The hollow stems of upright blackberries can be home to solitary bees. Photo by Beth Bolles, UF IFAS Extension Escambia County
Another favorite site for solitary bees is in the ground. These ground nesting solitary bees should not be compared to yellow jacket wasps. Solitary bees are not aggressive. Mining or digger bees need some bare soil surfaces in order to excavate small tunnels for raising a few young. Maybe you have an area that does not need a complete cover of turf but is fine with a mixture of turf and ‘wildflowers’. A few open spaces, especially in late winter and early spring will be very attractive to solitary bees.
Beneficial solitary bee mounds in the ground of a winter centipedegrass lawn area. Photo by Beth Bolles, UF IFAS Extension Escambia County
One of our fastest disappearing homes for wildlife are natural cavities. In residential sites, we often prune or remove limbs or trees that are declining or have died. If the plant or tree is not a hazard, why not leave it to be a home for cavity nesting birds and mammals. If the dying tree is large, have a professional remove hazard pieces but leave a trunk about 10-15 feet tall for the animals to make a home. You may then get to enjoy the sites and/or sounds of woodpeckers, bluebirds, owls, flying squirrels, and chickadees.
by Carrie Stevenson | Feb 18, 2020
Several Extension offices in the Panhandle are collecting air potato bulbils for National Invasive Species Week. Photo credit: Esther Mudge, Escambia County
The non-native invasive air potato vine (Discorea bulbifera) has wound its way throughout Florida, from pine forests and creek floodplains to backyards. Their heart-shaped leaves are most noticeable in the spring and fall, where they can take over large areas, not unlike their fellow invasive vine, kudzu. In the fall, the plant produces a potato-like tuber called a bulbil, which grows above ground on the vine. The bulbils drop in the winter and then produce new vines the following spring.
The vine’s growth has been uncontrolled or kept back by herbicide for years, until researchers discovered a biological control insect known as the air potato leaf beetle (Liloceris cheni). In the vine’s native Nepal and China, the beetle controls growth by surviving on the leaves of the air potato, its sole food source. After extensive study, the USDA approved the use of these beetles in Florida to control the air potato vine population here. UF IFAS Extension offices statewide have participated in these beetle release programs, providing thousands of beetles to homeowners and property owners seeking to manage the invasive vine using a chemical-free technique. Left alone, air potato vines can smother full-sized trees, blocking the sunlight and causing them to collapse under the weight of the intertwined vines.
From 2012-2015, beetles were able to reduce air potato vine coverage and bulbil density by 25-70% (depending on location and density of beetle population). The active beetle-production phase of a UF IFAS grant has ended, but researchers are committed to the goal of reducing this nuisance species statewide.
To assist with this process, several Extension offices in the Panhandle are sponsoring a bulbil collection during National Invasive Species Week (NISAW, February 23-29). This effort will serve two important roles: to remove bulbils from the natural environment and to provide a seed source for university researchers seeking to grow air potato vine in a controlled environment, sustaining a continued population of air potato beetles for distribution.
For more information on Air Potato Vines and Leaf Beetles, visit https://bcrcl.ifas.ufl.edu/airpotatobiologicalcontrol.shtml or contact your local County Extension office.
by Matt Lollar | Jan 13, 2020
Scale insects on a cabbage palm (Sabal palmetto). Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
This week I was on a couple site visits to look on some cabbage palms (Sabal palmetto) and some banana shrubs (Michelia figo). The palms had a white, waxy substance on their frond petioles and the banana shrubs had white specs on the tops of their leaves. Upon further investigation, I realized the waxy substance and specs were both different species of scales. Scale insects are serious pests of a number of ornamental plants. Here in Florida there are 13 different families of scales with the most common being armored scales, soft scales, and mealybugs. Scales have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants. Heavy infestations cause extensive leaf yellowing, premature leaf drop, branch dieback, and eventually plant death.
Scale Biology
The life cycle of a scale begins with eggs being laid beneath wax coverings or beneath the adult female. Eggs typically hatch in 1 to 3 weeks. The newly hatched nymphs, called crawlers, move around a plant until they find a spot to feed. Once a feeding site is located, their piercing sucking mouthparts are inserted into the plant and the crawlers begin to feed and grow. The males of many scale species develop wings as adults and fly to other plants to reproduce.
Magnolia white scales on a banana shrub (Michelia figo). Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
Armored Scales
Armored scales get their armor by secreting a waxy covering over their bodies that is not attached. The scale lives under this covering and uses it as a protection to feed under. Armored scales can be almost any color or shape and range anywhere from 1/16 to 1/8 inch in diameter. For females, these shapes range from circular to oval to long and slender. The males typically have coverings that are more elongate and smaller than the females. As adults, the males are tiny, winged, gnat-like insects and are rarely seen.
Gloomy scale (Melanaspis tenebricosa) with armored covering removed. Photo Credit: A. G. Dale, University of Florida/IFAS
Soft Scales
Similar to armored scales, soft scales secrete a waxy covering, but it is attached to their bodies. Soft scales can be a number of colors, shapes, and sizes and range anywhere from 1/8 to 1/2 inch in diameter. Their shapes vary from spherical to nearly flat.
Population of adult and immature tuttle mealybugs (Brevennia rehi) on a blade of zoysiagrass. Photo Credit: Lyle J. Buss, University of Florida/IFAS
Mealybugs
Mealybugs are soft-bodied insects that possess a covering of flocculent, white, waxy filaments. They are about 1/8 inch in length and usually pinkish or yellowish in color. Mealybugs have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants. Mealybug damage produces discolored, wilted, and deformed leaves.
Scale and Mealybug Management
- Cultural Control – Plant inspection prior to purchase or installation is the first line of defense against a scale or mealybug population. Make sure to inspect the undersides of leaves and plant stems. Infested sections of plants can be pruned and plant material should be cleaned from the planting area and discarded. Also, you can increase air flow and decrease humidity by proper installation and pruning. Over-fertilizing can also increase pest populations.
Larva of a brown lacewing. Credits: Lyle Buss, University of Florida.
- Biological Control – Predators, such as ladybugs and green lacewings, are usually present in large enough numbers to suppress scales and mealybugs to a desirable threshold. However, broad-spectrum insecticides and bad weather can reduce predator numbers. Look for signs of predation by inspecting dead scales for jagged holes in their waxy coatings. If predation signs are present, use more selective chemical controls and oils as opposed to broad-spectrum products.
- Chemical Control – Timing is everything when it comes to managing scale and mealybug insects. Crawler activity is more pronounced with the flush of new plant growth in the spring. Before application, prune infested plant parts off first to promote greater penetration of insecticides into the foliage. Dormant Oils are often used in the winter to smother scale insects. These are good choices to implement because they don’t harm non-target or beneficial insects. Care must be taken to read the label and use them at the correct temperature, since use in hot weather may burn foliage. Contact products (acephate, bifenthrin, carbaryl, etc.) must be applied to inhibit the crawler stages of these insects and systemic products (acetamiprid, imidacloprid, thiamethoxam, etc.) can be used on the sessile growth stage. Plants should be sprayed thoroughly to the point of drip or “run off” from leaves, twigs, and stems. Repeated applications may still be necessary even if the timing is right, as crawler populations are often large and crawlers like to hide under old waxy scales. Systemic drenches are also a viable option. With good spray coverage, horticultural oils can kill scales at all stages of growth. Refer to the product label for phytotoxicity and temperature guidelines. Even after successful treatment, the outer coatings of the scales may remain on the plant material for weeks, which can be unsightly. The best way to determine if scales are dead is to squeeze them. They will be dry when squeezed if they are dead and they will ooze liquids if they are living (they were at least alive to the point of being squashed).
For insect identification and additional information on scale control, please see:
A Guide to Scale Insect Identification
UF/IFAS Featured Creatures
Your County Extension Office
by Molly Jameson | Dec 10, 2019
This velvet ant (Dasymutilla occidentalis) is a female, and therefore has no wings, but it does have a long ovipositor that could inflict a painful sting if provoked. Photo by Johnny N. Dell, Bugwood.org.
The Docile Nature of a Cow Killer
Has a large, flashy, bright red-orange, fuzzy ant-like creature ever captured your attention? It may have been the infamous velvet ant, otherwise fittingly known as “cow killer” for the very painful sting it can inflict. A solitary species that builds no nest of their own, you’d likely only see one at a time, perhaps crawling over bare soil or along a tree root.
This velvet ant (Dasymutilla occidentalis) is a male, and therefore has wings, but no stinger. Photo by Johnny N. Dell, Bugwood.org.
Velvet ants are actually not ants at all, but wasps. They are wasps that – although capable of stinging humans and other large animals – are not aggressive and have venom with relatively low toxicity (less than that of a honeybee). That said, an accidental sting by the female’s long ovipositor inflicts serious pain that one would not soon forget.
Velvet ants are in the Mutillidae family, which contain about 8,000 species throughout the world. But only fifty Mutillidae species can be found in Florida, as most prefer arid regions, such as the southwest United States.
If you see a velvet ant with wings, rest assured, it is a male. Although capable of flight, males are incapable of stinging, as they lack stingers. Females, who lack wings, need a suitable host to be able to lay their eggs, and they spend most of their time looking for one. They rely mainly on mature larvae (such as pupae and cocoons) of other solitary species in the Hymenoptera order (other wasps, bees, and ants) to parasitize. That is, a female adult velvet ant will forcibly enter a nest to deposit an egg beside its larval victim. When the velvet ant larva emerges, it will consume this host within about a week before it matures and emerges from the host nest to seek a mate.
Adult velvet ants feed on flower nectar. Photo by Whitney Cranshaw, Colorado State University, Bugwood.org.
The “velvet” part of velvet ant refers to the dense heap of hairs covering top portions of its body, which is usually a bright shade of red or orange, although some species are gold, silver, black, or white. Velvet ants use their aposematic coloration to their advantage. They tell potential predators “don’t mess with me” through their visually striking, often red and black “stripes,” that act as a visual defense mechanism.
Beyond coloration, a female velvet ant will also produce a warning sound when provoked, further evidence that she wishes to remain docile, rather than fight. Despite their gory parasitism on which they rely to reproduce, adults simply feed on nectar.
So, the next time the mesmerizing bright red streak of a velvet ant catches your gaze, keep your distance, but have no fear, for this cow killer comes in peace.
by Carrie Stevenson | Nov 7, 2019
A female striped lynx spider protects her egg sac. Photo credit: Carrie Stevenson, UF IFAS Extension
With Halloween just behind us, some of us may still have fake spiders in our yards and cotton webbing all over the shrubbery. Spiders (along with bats) are among those creatures feared and demonized in folklore this time of year. It is important to remember, however, that both organisms are important predators and managers of our insect population.
Last week during a walk on the Extension property, I came across a large brown spider hovering protectively near her egg sac. Perched in a newly planted pine tree, I saw no obvious web. Instead, the spider loosely wrapped the pine’s needles with silk, forming a support structure for the relatively large egg sac.
Newly hatched striped lynx spiderlings on silk scaffolding covering a plant. Photograph by Laurel Lietzenmayer, University of Florida.
On further research, I learned that this female striped lynx spider (Oxyopes salticus) would have mated just once, after responding to a male’s courtship display (involving drumming and elaborate leg touches). She would have produced the egg sac 1-4 weeks after mating, attaching it to the pine needles, and will tend to it until her young emerge 20 days later. Up to five days after hatching, lynx spiderlings disperse by “ballooning” from the plant—they release a silk thread into the air, allowing the wind to carry them off like a tiny skydiver. Those spiderlings will mature into adults by 9 months, living their entire lifespan in just one year.
During that year, though, lynx spiders are important predators of pest insects. Instead of catching bugs in a web, they stalk their prey like a big cat—hence the name, “lynx.” They prey on many fly species, but also on bollworms and green stinkbugs that are major pests of cotton and soybean crops. These spiders are beneficial and highly vulnerable to insecticides.
by Mark Tancig | Jul 11, 2019
An adult firefly showing off its characteristic beetle wings and bioluminescent abdomen. Credit: Art Farmer, Creative Commons.
Many of us have memories of warm summer nights watching fireflies. Some of us might have even chased and caught a few to put in mason jars for observation, fascinated by their glowing abdomens. Floridians have the best chance to see these unique insects, as we have more known species than any other state. Recently, I’ve had many folks say that they see less fireflies these days, which got me looking into how these creatures live and what researchers know about their numbers.
Fireflies are actually a type of beetle in the Lampyridae family. They go through complete metamorphosis, meaning their immature larvae look completely different than the adults. A very unique characteristic of the family is the ability to produce light, known as bioluminescence. They do this in a very efficient way, creating very little heat, through the reaction of luciferin and luciferase along with oxygen, some energy, and other compounds. These light-producing compounds serve a dual purpose, warding off predators and attracting mates. The larvae of all Lampyridae benefit from the offensive taste of the compounds while only some adult Lampyridae use bioluminescence to attract mates. Each species of firefly has specific patterns of flashes. Males have the showiest light displays while females use more conservative light shows to signal back to potential mates.
Firefly larvae taste bad to predators due to the compounds that produce light. Credit: Gerald J Lenhard, LSU, bugwood.org.
Larvae of fireflies live in the soil and feed on slugs, snails, earthworms, and other soft-bodied insects. The larvae develop in the soil during cooler months, preferring moist habitats, and emerge as adults in the late spring to early summer. Some species may emerge in the early spring. Adult fireflies feed on nectar and honeydew, though some females prey on smaller firefly species by fooling males close to them through light signaling. Adults with the ability to produce light are active at night, while non-bioluminescent adults are active during the day.
An adult firefly. Credit: Mirko Schoenitz, iNaturalist.org.
Entomologists specializing in fireflies have raised the concern that these classic summer-time insects are in decline. Reasons for the decline are associated with increased urbanization. Loss of suitable habitat and increased pesticide use, including broad-spectrum insecticides for home lawn insect control, negatively affect firefly larvae living in the soil. Researchers also point to urban light pollution as another cause. The ever-glowing night sky in populated areas, originating from house lights, ball fields, parking lots, and roadways, disturb firefly communication and reproduction.
UF/IFAS infographic about fireflies. Credit: UF/IFAS.
Homeowners can help fireflies by leaving small patches of unmanaged landscaped areas, such as along property lines, and only using insecticides when absolutely necessary. If pesticides are needed to control lawn and garden pests, the use of more selective, low-toxicity products is preferable. Turning off unnecessary outdoor lighting is another step homeowners can take to encourage firefly populations. Residents of homeowner associations can work together to minimize excess lighting community-wide, saving electricity and maybe even fireflies.
For more information on fireflies and best practices to control lawn and garden pests, contact your local county extension office.
