by Les Harrison | Aug 10, 2018
Looks, as the old saying goes, can be deceiving. It is a cautionary pronouncement from experience, usually painful and expensive, to serve as a warning to those who follow and hopefully avoid similar complications if they listen.
In most situations a threat in nature can be easily identified and avoided with a little effort. Except for those situations where the careless or clueless individual blunders into problems, a little observation and logic dictates the potential outcome from a close encounter.
Yellow jackets have stingers, so they must stink something. Alligators would not have all those large and pointed teeth unless they needed to bite something.
Those assumptions are easily deduced by anyone who uses even the slightest quantity of judgement and forethought. Unfortunately, there are occasions where the potential agony is disguised by bright colors and a benevolent appearance.
Such is the case with the caterpillar of the Io moth. Automeris io, this insects entomological name, is a large native moth.
This insects’ range extends from south central and maritime Canada to the eastern half of the U.S. It is found in every Florida County, even into the Keys.
The wingspan of this moth can reach an impressive three and a half inches. Males of this species tend to have a slightly brighter appearance than the females.
Both sexes have large eye spot on each hindwing as a defense device. When revealed, the spots appear as the eyes of predatory creature meant to bluff other aggressors into retreating.
Adults of this species live only a week or two, so reproduction is a priority activity. Luckily, at least for the parents, there are plenty of host plants in north Florida.
Oaks, sweetgums, redbuds, and ash are among the choice meal sites for the developing caterpillars. The eggs are commonly laid in clusters of 20 or more and the caterpillars go through five development stages before reaching adulthood.
Unlike the parents which are active almost exclusively at night, the larvae spend their days hidden in the tree leaves they are consuming. These caterpillars are quite animated and active, frequently seen moving inline from one feeding site to another.
Initially orange, they change to a lime green as they mature. They also develop clusters of spine strategically place across their plump bodies.
Photo Caption: The colorful Io moth caterpillar is covered by fragile spines. Each contains a painful venom for anyone who physically contact this insect larvae.
Distinct from their parents’ eyespot bluff, the spines are a serious defense designed to assure the caterpillars reach maturity unmolested by birds or other predators which would otherwise find them a suitable snack option.
Unlike a pit viper which injects venom via a syringe-like fang or a stingray which retains its barb in a venom saturated sheath, this caterpillar’s spines work differently. Each spine contains a sac filled with the defensive solution.
When contact is made with the hollow spines, deliberately or accidentally, the fragile structure breaks and releases the toxin. The pain is almost instantaneous, intense, and can be a serious health treat for those who have an allergic reaction.
Not usually seen on the ground this caterpillar can be encountered on lower limbs, to the detriment of the unlucky individual. The colorful, toy-like appearance hides a very different reality.
To learn more about north Florida’s stinging caterpillars, contact the local UF/IFAS County Extension Office. Click here for contact information.
by Julie McConnell | Sep 29, 2015
Giant Swallowtail on citrus leaf. JMcConnell, UF/IFAS
Adult butterflies are pretty easy to attract to your landscape if you provide flowering plants, but getting them to lay eggs in your garden is a little trickier.
Butterflies go through complete metamorphosis which means that they have four main life stages. The first is the egg, second they hatch into caterpillars (larvae) which feed and molt many times, the third stage is the pupa or chrysalis, and finally they emerge as colorful adults. Complete metamorphosis is considered a more advanced life cycle than incomplete and one of the reasons is because most insects that go through this process do not compete for food at different life cycles. For example, the gulf fritillary butterfly larvae needs passionflower (Passiflora spp.) to feed on – no other plant type will do. The adults visit many flowering landscape plants such as zinnias, butterfly bush, pentas, etc. The adults are feeding on nectar while the caterpillars are eating foliage.
Because the larvae are very host specific, you must offer the correct plant to attract particular butterflies. Luckily, we have many options in the Florida panhandle! Just remember if you would like to attract butterfly breeding to your yard, you must sacrifice some foliage to support the caterpillars.
• Gulf Fritillary – Passionflower
• Monarch – Native milkweed
• Giant Swallowtail – citrus
• Eastern Black Swallowtail – plants in the carrot family including dill, celery, fennel, and parsley
• Tiger Swallowtail – sweet bay magnolia, tulip poplar, black cherry
• Zebra Swallowtail – pawpaw
• Luna Moth – walnut, hickory, sweetgum, persimmon, winged sumac
If you would like to know more about individual butterfly species please visit UF/IFAS Entomology & Nematology’s Featured Creatures website.
by Roy Carter | Jun 10, 2015
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
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
by Taylor Vandiver | Sep 9, 2014
What’s eating my lawn? Does your grass look ragged in areas, as if someone randomly used a weed-eater here and there? Are you noticing brown patches that have a closely clipped appearance compared to other areas of your lawn? Your turf may be playing host to Tropical Sod Webworm.
Sod webworm damage in a home lawn. Photo courtesy UF/IFAS.
Sod webworm damage is subtle at first. You have to look closely to notice larval feeding damage. However, an easy indication of their presence is the light tan/brown colored moths, which are the adult stage of the pest. You may see them fly up as you walk through your lawn or if you disturb a nearby bush. The moths do not cause any damage to the turf, but they are depositing eggs, which will result in their offspring, the caterpillars, who do all the chewing damage.
The larvae are gray-green and have spots on each segment. The mature larvae can be up to 1 inch in length. Larvae will curl up in the soil during the day and feed at night. So if you happen to notice caterpillars feeding during the day, it’s probably not sod webworm. You will notice chewed notches along the leaf blade, holes in the leaf and even leaf blade skeletonizing. The older the larvae are, the more they will eat. Damage may start out as a ragged appearance in your turf, which can be hard to diagnose. However, if left unchecked, sod webworm can cause considerable injury to your lawn.
Sod webworm larvae. Photo courtesy UF/IFAS.
If you are uncertain of their presence you can always use a soap drench to flush out larvae. Mix 2 tablespoons of dish soap with 2 gallons of water and pour it over a damaged area (about 3 square ft.). The soap mixture will irritate the pest and bring them to the surface so you can easily identify them. If nothing appears in the area tested move to another damaged site and try again. Here is a link to a video that will give more information on identifying Tropical Sod Webworm.
Tropical Sod Webworm is considered a pest of all warm-season turfgrasses. However, St. Augustinegrass is most commonly affected. The best way to prevent a pest infestation is to use proper cultural maintenance practices for your lawn type. However, if the pest does appear, chemical control should be targeting the larvae stage of the pest. There are multiple products marketed to control lawn caterpillars. However, you may want to consider using B.t. (Bacillus thurengiensis), which is a bacterium that will only harm caterpillars and not bother beneficial insects that may be in your lawn. For more information you can contact your local extension office.
by Julie McConnell | Jul 1, 2014
Panhandle residents have seen caterpillars in abundance this June. One common visitor to pecan trees is the Walnut Caterpillar Datana integerrima. The walnut caterpillar has a very narrow host range and feeds only on trees in the Juglandaceae family which includes walnut, pecan, and hickory trees. They are sometimes seen on other plant material, but feeding on non-host plants is unlikely.
Walnut caterpillar feed on the leaves of host trees through several growth stages and molts until they have reached the final larval instar and are ready to pupate into an adult moth. Their color changes from light green when newly hatched to reddish-brown to almost black with long white hairs as they mature. The caterpillars group together in large masses and may hang from each other and dangle from the tree branches when molting. Instead of creating a cocoon in the tree, the walnut caterpillar moves to the ground beneath the tree and burrows into the soil or leaf litter to pupate and emerges later as a moth.
What can you do if your pecan tree is hosting walnut caterpillars?
Although the numbers seen on trees may be alarming, a healthy tree can tolerate some feeding damage. Stripped branches may increases the chance of a lower yield of fruit because the removal of leaves does reduce the amount of energy the tree can produce, but overall health of the tree should not be significantly affected. However, many homeowners find falling caterpillars and their excrement unappealing and may decide to take steps to manage the population.
There are several natural enemies that feed on caterpillars, so avoid using a broad spectrum insecticide that might harm predatory insects and other animals. Consider using a biological control product such as Bt (Bacillus thuringiensis) that is only lethal to caterpillars. Other methods are “pick and squish” or drowning in a bucket of soapy water. Next year, in the spring, watch for masses of tiny green eggs on the underside of leaves and remove and destroy them before hatching.
For more information visit USDA Forest Service Forest Insect & Disease Leaflet 41 “Walnut Caterpillar”
