by Beth Bolles | May 5, 2016
Believe it or not, there is a beneficial ant that is found in many landscapes. If you see an interesting mound shaped like a small volcano, you likely have the pyramid ants. These ants form small nests in sandy soils and the mound will have a small opening in the very center.
Pyramid ant mound, about 5 inches across. Photo by Beth Bolles
Pyramid ants are not aggressive and do not sting. They are fast moving over the ground building the mound and searching for food. Ants will collect honeydew from other insects and the beneficial part is that ants hunt live insects including winged fire ants. By allowing the pyramid ants to remain in parts of your landscape, you may reduce the numbers of fire ants that can establish in that area.
When you see the distinctive pyramid ant mounds, remember the beneficial role they play in keeping pest species in check. Keep any baits away from these areas to protect the pyramid ants.
A group of small mounds. Photo by Beth Bolles
by Sheila Dunning | Apr 21, 2016
Mountain laurel. Photo credit: Sheila Dunning, UF/IFAS Extension.
If you are lucky enough to live on the southern Alabama edge of northwest Florida, you may want to see if you can find mountain laurel blooming now near the wooded creeks. Its native range stretches from southern Maine south to northern Florida, just dipping into our area. The plant is naturally found on rocky slopes and mountainous forest areas. Both are nearly impossible to find in Florida. However, it thrives in acidic soil, preferring a soil pH of 4.5 to 5.5 and oak-healthy forests. That is something we do have. The challenge is to find a cool slope near spring-fed water.
Mountain laurel blooms. Photo credit: Sheila Dunning, UF/IFAS Extension.
Mountain laurel (Kalmia latifolia) was first recorded in America in 1624, but it was named after Pehr Kalm, who had collected and submitted samples to Linnaeus in the 18th century. The wood of mountain laurel was popular for small household items. It is heavy and strong with a close, straight grain. However, as it grow larger it becomes brittle. Native Americans used the leaves as an analgesic. But, all parts of the plant are toxic to horses, goats, cattle, deer, monkeys and humans. In fact, food products made from it, including honey, can produce neurotoxic and gastrointestinal symptoms in people consuming more than a modest amount. Luckily, the honey is usually so bitter that most will avoid eating it.
Mountain laurel in its native habitat. Photo credit: Sheila Dunning, UF/IFAS Extension.
One of the most unusual characteristics of mountain laurel is its unique method of dispersing pollen. As the flower grows, the filaments of its stamens are bent, creating tension. When an insect lands on the flower, the tension is released, catapulting the pollen forcefully onto the insect. Scientific experiments on the flower have demonstrated it ability to fling the pollen over 1/2 inch. I guess if you don’t taste that good, you have to find a way to force the bees to take pollen with them.
The mountain laurel in these pictures is from Poverty Creek, a small creek near our office in Crestview. This is their best bloom in 10 years. Maybe you can find some too.
Native range of mountain laurel.
by Matt Lollar | Apr 14, 2016
Scales on a Chinese Elm.
Scales on a Chinese Elm.
Last week as I was basking in the shade of the Chinese Elms (Ulmus parvifolia) in my yard, I noticed some strange lumps on the twigs. Upon further investigation, I realized the “lumps” were 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.
The magnolia white scale. Credits: University of Florida
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.
Hemispherical scale on coontie. Credits: Lyle Buss, University of Florida
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.
Mealybugs. Credits: James Castner, University of Florida
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. 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 Matthew Orwat | Apr 7, 2016
This spring, most garden plants are putting on lots of tender new growth. The lush foliage is like a free lunch to aphids, whiteflies, mealybugs and thrips. Before broad spectrum insecticides are used to control these pests, consider the impact on beneficial insects. Insecticides that don’t measurably harm predatory beneficial insects include insecticidal soaps and all season horticultural oils, which kill soft-bodied insect pests at application. Here are several common beneficial predatory and parasitic insects that help keep the pests at bay.
Assassin Bug Zelus longipes
Assassin bugs are predators of several leaf feeding and sap sucking insects including the fall army worm and the Asian citrus psyllid. They trap their prey by holding onto it with their forelegs and secreting enzymes into the prey to dissolve the interior tissue. Then they ingest the dissolved tissue.
Lady Bug or Lady Beetle
These insects most commonly feed on aphids, most insect eggs, whiteflies, small caterpillars, scale and mealybugs. They provide a measurable benefit to gardens since they are such generalized feeders. The Lady Beetle larva look substantially different from the adult stage.
Third instar larvae of Hippodamia convergens. Photograph by Luis F. Aristizábal, University of Florida
Newly emerged adult Hippodamia convergens showing typical body markings. Photograph by Luis F. Aristizábal, University of Florida.
Soldier Bug
A different but closely related species of the stink bug, this predator uses its piercing / sucking mouthparts to feed on larval beetles and caterpillars.
Dorsal view of an adult spined soldier bug, Podisus maculiventris (Say), feeding on a mating pair of sumac flea beetles, Blepharida rhois (Forster) (Coleoptera: Chrysomelidae). Photograph by Lyle J. Buss, University of Florida.
Lacewings
The green and brown lacewing is often found around aphid infestations. The larva is the major predator, they make the biggest dent on aphid populations. In addition to aphids, lacewings also feed on scale, mealybugs and several species of insect eggs.
Adult brown lacewing (Neuroptera: Hemerobiidae). Photograph by University of Florida.
Larva of a brown lacewing (Neuroptera: Hemerobiidae) preparing to attack and feed on an aphid. The black-colored aphid to the right was probably parasitized by a wasp. Photograph by Lyle J. Buss, University of Florida.
Predatory Gall Midges
This aphid predator is easily overlooked because it is so small, and resembles the flower fly. They also feed on scale, thrips and mites.
Adult of the predatory gall-midge, Feltiella acarisuga (Vallot). Photograph by David R. Gillespie, Agassiz.
Larva of the predatory gall-midge, Feltiella acarisuga (Vallot). Photograph by Lance S. Osborne, University of Florida.
Flower Flies (Hover Flies)
Flower Flies actually resemble honeybees or bumblebees. People often run from them! The adult is an important pollinator for many crop species and feeds on nectar and aphid honeydew. This time it’s the larva which is predatory and is a voracious feeder of aphids. Large concentrations of larvae substantially reduce aphid populations in aphid infested gardens and fields.
Larva of Allograpta obliqua (Say), a hover fly. Photograph by James F. Price, University of Florida.
An adult male hover fly, Allograpta obliqua (Say). Graphic by Division of Plant Industry.
Parasitic Flies
There are many types of parasitic flies which parasitize a variety of insect pest species. They may inject their eggs into the host, or lay the egg on the surface of their host. Usually they are very small and not noticeable.
Parasitic Wasps
Most parasitic wasp species are tiny, fast and hard to notice. The average gardener is not aware of their rather plentiful existence. They are a common killer of grubs, caterpillars, whiteflies and aphids. They either insert their eggs into the organism or lay eggs on the surface of their host.
A group of adult Cotesia congregata (Say) wasps feeding on honey solution placed on the underside of a tomato leaf. Photograph by Justin Bredlau, Virginia Commonwealth University.
Big Eyed Bugs and Minute Pirate Bugs
While big eyed bugs and minute pirate bugs are not related, they perform similar functions in gardens and agricultural systems by feeding on chinch bug nymphs, psocids, leafhoppers, aphids, thrips, and mites. They are found in variety of ecosystems and do their job anonymously.
Adult bigeyed bug, Geocoris sp., feeding on a whitefly nymph. Photograph by Jack Dykinga, USDA
The minute pirate bugs are black with white markings. They prey on many small insects and eggs, including thrips. About 70 species exist in North America. Photograph by James Castner, University of Florida
References:
by Carrie Stevenson | Mar 29, 2016
Among the most fascinating natural phenomena in our area are the presence of dozens of species of carnivorous, or meat-eating, plants. Found in bogs, meadows, and seepage slopes with mucky, acidic soils and low levels of nutrients, these plants have adapted to their difficult conditions by developing ways to digest insects.These carnivores are best known by their common names; sundew, butterwort, bladderwort, and pitcher plants.
Sundew plants ready to feast
A meadow of white-topped pitcher plants in full spring bloom.
While there are six species of pitcher plants found in the panhandle and throughout the Gulf Coastal Plain, the “world’s largest concentration” can be found at Escambia County’s Tarkiln Bayou Preserve State Park. The “pitcher” part of the plant is actually a modified leaf, which is rounded into a hollow tube open at the top and partially covered by a hood. This hood is colorfully patterned, attracting insects also drawn to nectar inside the tubes. As insects crawl in, downward-facing hairs prevent them from escaping. They drown in the collected water within the tubes, then decompose via acids and enyzymes secreted by the plant into a “liquid fertilizer.” A handful of commensal animals, including flies, spiders, and small frogs, take advantage of the pitcher plants’ insect-trapping expertise and manage to avoid capture.
A guide to identifying all six of these pitcher plant species–white-top, parrot, trumpet-leaf, hooded, sweet, and yellow–can be found at the Florida Department of Environmental Protection’s wetland plant site. Now is the perfect time to see pitcher plants beginning to blossom.
While many people are familiar with pitcher plants, fewer notice the low-growing sundew. These plants may be smaller than a dime in circumference, and grow flat along very mucky soil in full sun. If shaded out even by relatively short grasses, sundew disappear. Their characteristic pinwheel-like appearance and deep red coloring help draw the eye if you look very closely. Sundews also excrete a sticky nectar, on which small insects get stuck and digested to provide nutrients to the plants.The leaves of butterwort plants work very similarly to sundews; they are typically bright green and succulent with sticky hairs that attract nutrients.
Bladderworts, also found in similar environments, use a different mechanism to trap insects. They actually have a bladder-like formation within their root system that opens and closes, siphoning water and unlucky insects in and out.
Regardless of their location, appearance, or method of trapping, carnivorous plants remain one of the most unusual, and interesting groups within the plant kingdom. Be sure to take the opportunity this spring to seek out a park or natural area populated with carnivorous plants–such as Tarkiln, Blackwater River State Park, or the public areas of Eglin Air Force Base and see them for yourself!
by Beth Bolles | Mar 28, 2016
The mining bees or adrenids are often seen in areas of landscapes that have little ground vegetation and loose soil. After mating, the female bee will excavate a very small tunnel in the ground that has several small cells attached to it.
Beneficial solitary bee mounds in the ground. Photo by Beth Bolles
The bee collects pollen and nectar to add to the cell and then lays a single egg in each cell. The emerging larvae feed on the nectar and pollen until it changes to an adult bee in the fall. There is only one generation a year. Although these solitary bees individually produce small nests, sometimes many will nest in close proximity to each other.
Solitary bee entering ground. Photo by Beth Bolles
Solitary bees are not aggressive and stings are quite mild. Most solitary bees can be closely observed and will elicit no defensive behaviors. Perhaps the most common stings that occur are when the sweat bee, which is attracted to moisture, stings when swatted. Males of some solitary bees, which can not sting, will sometimes make aggressive-looking bluffing flights when defending a territory.
Like the most famous honey bee, solitary bees play a beneficial role in the pollination of plants. Their activity in the spring is short-lived and no management is necessary.
