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Caterpillars with a Sting

Caterpillars with a Sting

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Saddleback Caterpiller, Image Credit Matthew Orwat UF/IFAS

The four major stinging caterpillars occurring in Florida are the Puss Caterpillar, Saddleback Caterpillar, IO Moth Caterpillar and Hag Caterpillar.  Some less common ones also occur in the state.  These caterpillars do not possess stingers, but have spines (nettling hairs) that are connected to poison glands.  Some people experience severe reaction to the poison released by the spines and require medical attention.  Others experience only an itching or burning sensation.

Stinging caterpillar’s feed on many pants, but they seldom are present in large enough numbers to cause serious damage.  Their stings, rather than feeding, pose the primary threat.  That’s why it’s important to learn to recognize and avoid these cantankerous crawlers.  My information on stinging caterpillars was provided by Extension Entomologist Dr. Don Short and Dr. D. E. Short of the University of Florida’s Institute of Food and Agricultural Sciences

The puss caterpillar is stout bodied, almost an inch long, and completely covered with gray to brown hairs.  Under the soft hairs are stiff, poisonous spines.  When touched, the spines break off in the skin, causing serve pain. The saddleback caterpillar has a more striking appearance.  It’s brown, with a wide green band around the middle of the body.  There’s a large brown spot in the middle of the green band, giving the appearance of a brown saddle on a green blanket.  The saddleback may exceed and inch in length, and is stout bodied.  The main poison spines are born on pairs of projections near the front and rear of the body.  There’s a row of smaller stinging organs along each side.

I O Moth Caterpillar, Image Credit UF Entomology

I O Moth Caterpillar, Image Credit UF Entomology

The IO moth caterpillar is pale green, with yellow and reddish to maroon stripes along the sides.  It often exceeds two inches in length, and is fairly stout bodied.  The poisonous spines, which form rows of bands across the body, are usually yellow with black tips.

The light brown hag moth caterpillar has nine pairs of variable length protrusions along its body, from which poisonous spines extend.  The protrusions are curved and twisted, giving the appearance of disheveled hair of a hag.

Most contact with stinging caterpillars occurs in the spring and summer.   As might be expected, children, campers, and gardeners are most frequent victims.  When playing or working outdoors in infested areas, it pays to wear a long-sleeved shirt, long pants, and gloves.

Reactions to caterpillars poison vary with an individual’s sensitivity.  Itching, burning, swelling, and nausea may be experienced.  In severe cases, fever, shock, and convulsions may occur.  If a person has a history of hay fever, asthma, or allergy or if allergic symptoms develop a physician should be contacted immediate.  In cases of milder reactions, a strip of adhesive tape should be placed on and pulled off the affected area repeatedly to remove the spines.  Then, apply ice packs, followed by a paste of baking soda and water.

Since so few stinging caterpillars are normally found on plants around the home mechanical methods usually offer the easiest means of control.  Just carefully remove and crush the caterpillars, or knock them into a pan of kerosene.  If a pesticide is needed, Bacillus thuringiensis (Bt), Seven or Malathion may be used in accordance with label directions for caterpillar control.

For more information on Caterpillars contact your UF/IFAS County Extension Service or visit www.http://edis.ifas.ufl.edu and see Publication 107 – Stinging and Venomous Caterpillars.

Puss Caterpillar, Image Credit University of Florida

Puss Caterpillar, Image Credit University of Florida

Tips on Controlling Ants

Tips on Controlling Ants

The proverbial picnic scene aside, ants are pests all of us have to deal with from time to time.  Both inside and outside our homes, they feed on and contaminate our food, they build ugly mounds on our lawns, and some ants can inflict painful bites or stings.

Several species of ants are found in Florida.  The most common can be grouped into three categories:  House-infesting ants, yard infesting ants, and carpenter ants.  In this article we’ll talk about ant biology and behavior and how to control them.

Florida Carpenter Ants. Photo credit: UF/IFAS.

Florida Carpenter Ants. Photo credit: UF/IFAS.

Ants have a life cycle similar to many other insects.  They go from egg, to larva, to pupa, to adult.  Eggs are almost microscopic in size and hatch into soft legless larvae.  The pupa resembles the adult ant, except it is soft, uncolored and immobile.  It can take from six weeks to two months from egg to adult.

Ants are social insects.  They live in colonies much like bees do.  Most colonies have a queen ant, male ants, and worker or female ants.  Colonies are started by queens, whose primary function is reproduction.  The queen may live for many years and is usually replaced by a daughter queen.  Males are produced in very old or large colonies, and their sole function is to mate with the unfertilized female, after which, they die.  Worker ants construct, repair and defend the nest, provide food for the colony, and take care of the young ants.

Most ants are omnivorous, which means they will eat anything, through some do have specialized food habits.  Ants locate food by random searching; when one ant finds food, she informs the other workers in the colony.  The exact method of communication is unknown, but in some cases, ants can leave scent trails that other ants can follow to the food source.

Because ants are attracted to any type of food or food particles, your best bet to controlling ants inside your home is to keep it very clean.  Store food in airtight containers.  Never substitute insecticides for inadequate housekeeping.

The key to eliminating ants is locating and destroying the colony.  Sometimes this can be a real problem, because ants are very adaptable. Outdoor nesting species can sometime nest indoors and vice versa, depending, on the food supply.

To find the ant colony, you have to watch the movement of the ants very closely.  Outdoors, many ants are easy to locate, because they deposit earth on the soil surface, and form ant hills.  But some outdoor ants build nests under house foundations, in decaying logs, and tree trunks.  These can be difficult to locate indoors.  Ants may nest in walls, behind baseboards, in cracks, and in decaying wood.

Spray, dusts, granules, and baits can be useful in controlling ants.  When using these products, treat baseboards, door and window frames, and cracks and crevices between walls and flooring.  Treat all areas where ants appear to have trails. If the nest is located, apply an insecticide to the nest according to the pesticide label.

For more information:

Ants

Fire Ants

Carpenter Ants

 

S.H.A.R.E. During National Pollinator Week – June 15-21, 2015

S.H.A.R.E. During National Pollinator Week – June 15-21, 2015

Green-headed Coneflower with American Copper and Bumble BeeEveryone with a landscape can make a difference for pollinators.  Simply Having Areas Reserved for the Environment enables homeowners, land managers, farmers, individuals, corporations, schools, roadside managers, and golf courses to increase the number of pollinators in the area by making conscious choices to include plants that provide essential habitat for bees, bats, birds, butterflies, moths, beetles, and hummingbirds.  What better time than during National Pollinator Week, June 15-21, 2015.

Initiated and managed by the North American Pollinator Protection Campaign, National Pollinator Week was unanimously approved and designated by the U.S. Senate in 2007.  Each year since, the U.S. Secretary of Agriculture has signed the proclamation in an effort to address the urgent issue of declining pollinator populations.

Worldwide there is evidence that pollinating animals have suffered from loss of habitat, pesticide misuse, competition from invasive species, disease, and parasites.  Many pollinators are federally “listed species”, meaning that there is documented information confirming the disappearance and/or significant population reduction in natural areas.  The United States has lost over 50% of its managed honeybee colonies over the past ten years.  The European Union has been so concerned that they invested over $20 million investigating the status of pollinators in Europe.redbudbee5

Pollinator health affects everyone.  Worldwide, roughly 1,000 plants grown for food, beverages, fibers, spices, and medicines need to be pollinated by animals in order to produce the goods on which we depend.  Food and beverages produced with the help of pollinators include: apples, blueberries, chocolate, coffee, melons, peaches, potatoes, pumpkins, vanilla, almonds, and tequila.  In the U.S., pollination by honey bees, native bees, and other insects produces $40 billion worth of products annually.

Passion-FlowerThe native plants that can be identified and preserved or introduced include trees, shrubs, vines and perennials.  Some of them include:  Eastern Redbud (Cercis canadensis), Highbush Blueberry (Vaccinium spp.), Passionflower (Passiflora spp.), Coreopsis (Coreopsis spp.), Goldenrod (Solidago spp.), Black-eyed Susan (Rudbeckia hirta), and Butterfly Milkweed (Asclepias tuberosa).  Simply identifying and avoiding damaging many of the existing native plants will allow anyone to provide important homes and food for many different pollinating animals.  During National Pollinator Week S.H.A.R.E. your space.

 

For additional information:

UF Native Buzz

Gardening for Pollinators

Minimizing Honey Bee Exposure to Pesticides

The Xerces Society

 

Tent Caterpillars: An Unwelcome Spring Guest

Tent Caterpillars: An Unwelcome Spring Guest

Uninvited guests can sometimes be fun and entertaining, bringing spontaneity to an otherwise predictable schedule. Sometimes the surprise guest is just an unpleasant distraction with no redeeming virtues.

The unanticipated knock on the door can bring both scenarios to mind. Almost everyone has an enjoyable cousin who regales listeners with amusing tales, and picks up the check for dinner.

Likewise, there are those potential callers with parasitic qualities, the appetite of a market hog, and initiative of a sloth. The Eastern Tent Caterpillar is one such visitor in north Florida.

These native caterpillars build large, thick nests on the branch forks and crotches of many kinds of trees, seeming to always choose the prized specimens highly valued by the homeowner. The silky tent shaped nests are easy to see and identity in host trees.

The caterpillars emerging in the spring of 2015 were laid in the spring of 2014. The adult moth lays her eggs in a single batch in May to July in the panhandle. There are 200 to 300 eggs laid in the group.

The mass of eggs are shiny, reddish-brown and look like dried foam. They are ordinarily about six inches back from the tip of a thin twig in host tree.

In approximately three weeks the eggs contain fully formed caterpillars, but the small caterpillars remain in the eggs until the following spring.

In late-February to mid-March they chew their way through their egg shells ready to eat their host tree that is entering the spring budding period with plentiful tender vegetation.

The voracious larvae immediately infest and, if in sufficient numbers, defoliate plum, cherry and many others. Normally the trees recover after a few weeks, but weakened or diseased trees may die.

When not eating, the newly hatched caterpillars construct their silk tent. The caterpillars use a pheromone trail to guild them back home when foraging is done.

A social insect, the eastern tent caterpillars congregate at their specific tent during the night and in rainy weather, expanding it to accommodate their growing size. These caterpillars do not feed within their nests.

The caterpillars disperse to colonize new areas when maturity is reached. They construct cocoons in protected places once they have sufficiently scattered.

Birds are not attracted to these hairy caterpillars. If they have a heavy concentration of black cherry leaves in their diet, the caterpillars will have a bitter acrid taste.

Parasitic wasps and weather are the two most common causes of caterpillar death. These caterpillars are especially susceptible to cold weather once they have emerged from their eggs.

About two weeks later, an adult moth emerges to begin the process again. Mating and egg laying commonly occur within 24 hours of the moths emerging from their cocoons

These brown moths are nocturnal and are seen flying only at night. They are an inch to two inches wingtip to wingtip at maturity and easy to overlook.

Tent Caterpillars are quick to hatch and eat their way through home landscapes.

Tent Caterpillars are quick to hatch and eat their way through home landscapes.

Unfortunately, once they arrive for a visit they always overstay their welcome.

Contact your local UF/IFAS County Extension Office to learn more about Eastern Tent Caterpillars in north Florida.

 

Insect Problems in the Heat of Summer

Insect Problems in the Heat of Summer

Florida soft scale

Florida soft scale. Photo credit: UF/IFAS.

Scale insects are one of the most serious problems homeowners face on ornamentals this time of year.  The most common are armored scale, soft scale, and mealybugs.   They cause damage by sucking plant fluids from the leaves, stems, and sometimes roots.  Some species feed on the underside of the leaves which can appear as yellowing spots or chlorotic lesions.  Heavy infestations can cause extensive leaf yellowing, premature leaf drop, branch dieback, and plant death.

The life cycle starts when the eggs are laid beneath a waxy covering or beneath the adult female.  After the eggs hatch two to three weeks later, the nymphs (crawlers) move around the plant until they find a suitable feeding site.  Crawlers then insert their straw-like mouthparts into the plant and begin to feed and grow.  The male often develops wings and flies to locate a mate.

Armored scale nymphs. Photo: UF/IFAS.

Armored scale nymphs. Photo: UF/IFAS.

Armored scale is distinct from other types of scales because they secrete a waxy covering over their body that is not attached to the body. The scale lives and feeds under this covering ranging 1/16 to 1/8 inch in size. They can be any color or shape, depending on the species. Armored scale does not produce honeydew.

Armored scale. Photo credit: UF/IFAS.

Armored scale. Photo credit: UF/IFAS.

Soft scale also secretes a waxy covering but it is attached to the bodies. Soft scales vary in color, size, and shape.  They are circular shaped and range from 1/8 to ½ inch in diameter. Because they consume so much plant sap, they excrete a lot of sugary liquid called honeydew. Honeydew is the sticky liquid found on the leaves.

Mealybugs. Photo credit: UF/IFAS.

Mealybugs. Photo credit: UF/IFAS.

Mealybugs are soft bodied insects that are often covered with cottony white filaments.  They are 1/8 inch in size and feed on all parts of plants.  Injured plants have discolored, wilted, and deformed foliage.

Sooty mold is caused when mealybugs and soft scales excrete large amounts of honeydew which provides an excellent medium for the growth of the black fungus.  Sooty mold is not only unattractive; it slows down the growth of the plant as it interferes with photosynthesis.  Over time, with the control of the insect population, the sooty mold will weather away. Ants can also play a big factor in controlling sooty mold as they will feed on the honeydew.

Sooty mold. Photo credit: UF/IFAS.

Sooty mold. Photo credit: UF/IFAS.

To control scale and mealybugs, avoid over-fertilizing and monitor your plants often. If the infestation becomes over-bearing, spray a fine mist of Horticultural Oil on the foliage. Avoid spraying in the summer heat because of damaging foliage. Other chemicals that can be used if necessary are Sevin dust and Malathion.

 

Insectary Meadows Provide Food for Pollinators and Homes for Good Bugs

Insectary Meadows Provide Food for Pollinators and Homes for Good Bugs

Bees have been disappearing at an alarming rate and continue to vanish without a trace. Why should anyone care? Well, they matter a lot more than most people think. Bees are the overwhelmingly dominant pollinator for most food crops. Native bees in the United States are responsible for pollinating over $15 billion worth of agricultural commodities annually. However, native bee populations are in decline due to habitat loss. At the same time, managed colonies of European honey bees have suffered a 50% decline over the past few decades. Numerous other pollinating insects are facing the same fate.

European honey bee. Photo credit: UF/IFAS.

European honey bee. Photo credit: UF/IFAS.

As the spring planting season is upon us, it’s exciting to think about all the wonderful produce we will have this summer. But, without pollinators many of these crops would not be available. The majority of fruit and vegetable food sources we eat are dependent on insect pollinators. One of every three bites of food Americans consume comes from a plant visited by bees or other pollinators.

As declining numbers of farmers work to meets the need of increasing populations, they are forced to make choices on alternative to chemicals for pest control. “Good bug blends” of flowers can help attract pollinators as well as beneficial insects that suppress harmful pests. Establishment of these meadows can be done on a small or large scale and in any habitat. One approach to “bring back the pollinators” is to intercrop with blooming plants that attract insects. Selecting a diversity of plants with different flower sizes, shapes and colors, as well as various plant heights and growth habits, will encourage the greatest numbers of pollinators. It is important to provide a continuous source of pollen and nectar throughout the growing season. At minimum, strive for three species to be blooming at any one time; the greater the diversity the better.

To enhance the garden, choose flowering plants that also provide shelter for beneficial insects. Many companion plants are suitable habitat for predators and parasitoids. Research in Florida has demonstrated that predatory minute pirate bugs can build to high numbers in sunflowers. The favorite food of minute pirate bugs is Western flower thrips. So, planting sunflowers on the perimeter of vegetable crops, such as peppers, can greatly reduce the damage caused by the thrips. Similar results were found with the planting of sorghum to attract beneficial mites and intercropping with buckwheat to house syrphid flies and parasitoid wasps. The garden vegetables experienced fewer spider mite, whitefly and aphid problems. Crimson clover, Hairy vetch and cosmos are other annual seed crops that can aid in attracting pollinators and harboring beneficial insects.

Blue Mistflower. Photo Credit Mary Derrick, UF / IFAS Extension.

Blue Mistflower. Photo Credit Mary Derrick, UF / IFAS Extension.

Insectary meadows can be created in the landscape and along roadways, not just in the garden. For more permanently planted areas, native wildflowers, grasses and woody plants serve as larval host plants for butterflies, and also provide nesting and overwintering sites for bumble bees, predacious beetles and other beneficial insects. Native perennial wildflowers such as blanketflower, tickseed, black-eyed Susan, partridge pea, narrowleaf sunflower, milkweed, beebalm, goldenrod and silkgrass can be installed in the spring as potted plants or seeded in the fall. Seeds require exposure to cold temperatures and damp conditions before germination can occur. In Florida, the best time is November to February.

Though grasses do not offer nectar or high-quality pollen, it is often useful to include at least one native bunch grass or sedge. Short, clump-forming grasses are preferable to large, spreading grasses. Hedgerow planting of woody species is a way to provide winter-blooming plants vital for supporting pollinators. Woody plants and grasses provide more than forage for pollinators, as many native bee species nest in the stems of plants or in the undisturbed ground underneath plantings. Suitable grasses include: beaked panicgrass, purple lovegrass, Muhly grass, broomsedge,little bluestem, wiregrass and toothache grass. Favored woody species that make good “beetle banks” include: fetterbush, American beautyberry, saw palmetto, Chickasaw plum, red maple, sparkleberry, Dahoon holly, redbud, blackgum, magnolia, buttonwood and sourwood.

Regardless of whether the objective is to establish herbaceous or woody vegetation, the time and effort spent on eradicating undesirable plants prior to planting will result in higher success rates in establishing the targeted plant community. Choose level, open sites that receive full sunlight and have limited weed populations.  If perennial weeds are a problem, the use of herbicides that have no soil residual (e.g. glyphosate) may be necessary.

For more information on establishing planting for pollinators visit: www.xerces.org/pollinator.