Polk County FL Horticulture

Mosquito Borne Viruses Pose Potential Threat to Florida/Polk County

2014-07-11T12:26:00.000-04:00

Aedes albopictus - Asian tiger mosquito
(photo by James Gathany)

Aedes aegypti adult (photo by James Gathany)

Both dengue and chikungunya are viral diseases whose vector is the yellow fever mosquito - Aedes aegypti. Chikungunya has as an additional vector, the Asian tiger mosquito (Ae. albopictus). Both Ae. aegypti and Asian tiger mosquito occur in Polk County but Ae. aegypti is much more common in the urban areas of south Florida.

Both species are container-inhabiting mosquitoes; often breeding in unused flowerpots, spare tires, untreated swimming pools, and drainage ditches. They thrive in urbanized areas, in close contact with people making them exceptionally successful vectors. Ae. aegypti bite during the day both indoors and outdoors while the Asian tiger mosquito bite mostly at dawn and at dusk.

The Florida Department of Health, recently reported that dengue fever had been confirmed in 24 people in Florida and chikungunya confirmed in 18 people. All of the infected people in Florida had traveled to the Caribbean or South America and could have become infected there, according to Walter Tabachnick, director of the Florida Medical Entomological Laboratory in Vero Beach.

The Florida Department of Health fear that individuals who become infected while traveling could pass the disease on to localized populations of either vector when they return to Florida which could result in a state epidemic.

Localized epidemics of dengue occurred in 2013 in a small neighborhood in Jensen Beach where 24 people were infected, and in 2009 and 2010 in Key West where 28 people were infected, according to state and federal reports.

The Caribbean Public Health Agency said this week that authorities in 18 Caribbean countries or territories had reported more than 100,000 confirmed or suspected cases of chikungunya.

A key feature shared by both dengue and chikungunya is that the fever comes on sharply about a week after exposure and lasts about a week. Dengue fever classically is accompanied by a headache, eye pain, prominent muscle aches, and swollen lymph nodes. Similarly, chikungunya features prominent headache and swollen lymph nodes, but instead of the muscle pain that is so characteristic of dengue, chikungunya entails marked joint pain and arthritis. A flat red rash that is covered with small confluent bumps is common beginning on about day 3 in patients with chikungunya, especially so in children.

At the present time there is no vaccine for either of these two virus diseases. Unfortunately some infected individuals may experience symptoms for months even years after infection. There are no specific medicines for these diseases. Using medicines other than aspirin may help to lower joint pain and fever.

There are several steps individuals can take to reduce localized mosquito numbers. Because these mosquitoes are container-inhabiting mosquitoes, one of the most successful and cost-effective methods to reducing populations is by preventing containers around the home from collecting water. By turning over empty flowerpots, properly maintaining swimming pools, and removing unused tires, you can greatly reduce the number of places mosquitoes have to lay eggs. Aerate birdbaths and make sure gutters are free of blockages. Clean pet bowls every day and always empty overflow dishes for potted plants.

For personal protection from bites, apply an insect repellant (DEET, picaridin, IR3535 and oil of lemon eucalyptus), and wear long pants and long sleeves when outside. Wear permethrin-treated clothing to repel and kill mosquitoes. Make sure door and window screens are intact. For more information on mosquito management, please visit the Florida Medical Entomology Laboratory mosquito management website at: http://mosquito.ifas.ufl.edu/Mosquito_Management.htm.

For information regarding mosquito management devices for the home, see http://edis.ifas.ufl.edu/in171

Flatid Planthopper on Cabbage Palm - A Vector for Texas Phoenix Palm Decline?

2014-07-09T16:34:00.000-04:00

Flatid planthopper (photo by D. Hazelbaker)

This flatid planthopper, Ormenaria rufifascia, is a common insect on some species of palms in Florida. The natural hosts of this planthopper in Florida are probably cabbage palmetto, Sabal palmetto, and saw palmetto, Serenoa repens, both native to this state, but this insect is sometimes seen on other palms.

Although it is usually not a serious pest, it sometimes indirectly causes aesthetic damage when dense populations produce honeydew that supports extensive coatings of sooty mold on the host plants. Both the adults and nymphs are conspicuous insects that often arouse people's curiosity.

It has been reported throughout the Florida peninsula and in Georgia. It may occur throughout the range of cabbage palmetto and possibly of saw palmetto - Florida and the Gulf Coast west to Louisiana and the Atlantic Coast north through the Carolinas.

The adults are rather large for planthoppers i.e., about 1/2 in length. They are highly conspicuous when seen on their usual feeding site, the lower surface of fan-leaf palms. They appear as tiny colorful sailboats. Their color is light blue-green, with various orange to reddish markings. There are no other species of similar appearance known to occur on palms in Florida, and very few species of Flatidae occur on palms anywhere in the world.

Both the nymphs and adults tend to occur on older rather than younger leaves, a behavioral trait that is characteristic of many insects that feed on palm leaves. The fact that the older fronds of palms are more or less horizontal and thus offer protection from sun and wind may be a factor in their being preferred by many kinds of insects.

Like the vast majority of species of the insect order this planthopper feeds by sucking plant juices, and thus draws energy from the plant. The populations of this insect usually do not consist of more than several individuals per frond, but dense populations may occur from time to time. As evidence, highly infested fronds are sticky with honeydew which supports thick crusts of sooty mold.

Populations of this insect are generally sparse and control measures would seldom be needed. The species has not been considered economically important enough to justify research on chemical or other methods of controlling it. In cases in which a few specimen palms become highly infested with this insect, it may be possible to eliminate them by simple physical means, such as a strong water spray.

This planthopper has recently has been suspected as a vector of Texas Phoenix Palm Decline of cabbage palms, but certainly not proven. If this insect is a vector for TPPD, it would be very bad news for cabbage palms as their range extends up through Florida into Georgia, the Carolinas and west to Louisiana as does this insect. So in effect every cabbage palm in the above areas could eventually be in danger of infection.

Flying Stinging Ants

2014-07-08T11:37:00.000-04:00

Winged Swarmer With Stinger

A few years ago, 2007 I believe, many Polk County residents were pestered by a stinging flying ant. I don’t think this insect has officially been given a common name, but the scientific name is probably Hypoponera punctatissima or a related species. This species is pretty common in many counties in Florida, but is seldom noticed or posed a problem for humans. The Extension Service was first alerted by residents in the City of Auburndale about being attacked by flying stinging ants. Little League baseball games in northern Polk County had to be cancelled and the Juvenile Assessment Center in Bartow had to have outside activities cancelled just to name a few occurrences. Since 2007 no other complaints about this insect have been reported to the Polk County Extension Service. However, this last weekend I received an e-mail from a resident of Punta Gorda who had been stung by flying ants - probably the same species. So, we may see them again this year in Polk County.

This is one of the very few swarming ants in Florida which have stingers and can inflict a painful sting. They are very aggressive during mating flights and can work their way under human clothing and sting at will. The sting can lead to a painful welt. They are not specificaly attracted to people as are mosquitoes, yellow flies, etc., they are just looking for a new nesting site and people happen to get in the way. They normally nest in soil or under objects resting on the ground, like potted plants, bags of soil, and toys. They also will nest in trash piles, rotten wood, and grass tussocks. They often are found in wet areas. The workers do not sing or bite as fire ants do. They hunt live insects for food.

There really aren't any control recommendations for this ant in the winged stage, unless you can find the colony where they are coming from. Since they are just dispersing from their nest and are not attracted to people, repellents are not going to be very effective. Their flight season is during warm, humid weather – the duration of the dispersal flight is not known. During 2007 in Polk County, the problem subsided after a week or two - maybe less.

Don’t confuse this ant with the elongate twig ant which is long and skinny and spends much of its time in trees. They commonly drop out of trees and land on people and can make their way under clothing. They have a ferocious bite something similar to fire ant bites. These are worker ants foraging for food – they do not have wings. The elongate twig ant winged swarmer’s do not sting.

Azalea Caterpillar

2014-07-07T12:42:00.001-04:00

Adult azalea caterpillar moth
(photo by James Baker)

The azalea caterpillar, Datana major G & R, is found in Florida from July through October on azaleas. Often, the caterpillars completely defoliate much of the plant before they are detected. So, take a good close-up look at your azaleas right now! While the caterpillar appears hairy, it is harmless to humans and can be picked off the bushes by hand.

The caterpillar is found in Florida as far south as Polk and Hillsborough Counties and azaleas are the only known hosts in Florida.

Eggs are deposited by the female moth in late spring in masses of 80 to 100 on the underside of the leaf.

azalea caterpillar (UF photo)

The first instar caterpillars feed in a cluster side by side unless disturbed. The first instar caterpillars are approximately 3/8 inch long after feeding for eight to ten hours. They remain gregarious and soon devour the entire leaf.

The first instar caterpillar is yellow with seven red longitudinal stripes and a black head. As the larva matures it becomes highly colored. The mature caterpillar is about two inches long, and predominately black, with a red last segment and eight broken yellow (occasionally white) lengthwise stripes. The head and legs are mahogany-red.

The adult moth is light brown with a wing expanse of 1 3/4 inches.

The semi-skeletonized leaves dry up, turn brown, and remain on the plant for several days. If disturbed some of the caterpillars drop one or two inches below the infested leaf and hang by a silken thread. When it is disturbed, the caterpillar raises its front and rear ends into the air. Young larvae skeletonize the leaves and the larger ones eat the entire leaf. In some parts of the South there may be a partial second generation, but one generation is usually the rule. It is thought to overwinter in the pupa stage.

Severe damage by azalea caterpillar
(photo by D Shibles)

Healthy azalea (photo by D. Shibles)

Most of the damage in the southeast United States occurs in August and September, but in Florida it continues through October. This caterpillar is pretty easy to control with commonly available pesticides such as Bug-Be-Gone Max (bifenthrin), Sevin (carbaryl), Orthene Insect Killer (acephate), Permetrol (peremethrin) and several others. More environmentally friendly products include Thuricide and Dipel (B.t. containing products) and Conserve (spinosad).

This time of year carefully inspect your azaleas for this pest. The caterpillars often go unnoticed until the damage is quite severe. Do not prune off branches with no leaves as the leaves will grow back in a few weeks. Any pruning at this time of the year will result in a loss of flower buds which are already forming on the leaf-eaten branches.

Caterpillars That Sting

2014-07-03T16:19:00.000-04:00

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 reactions to the poison released by the spines and require medical attention. Others experience only an itching or burning sensation.

Saddleback Caterpillar

Saddleback Caterpillar (UF photo)

This is a very unusual and striking insect. It is brown with a green back and flanks, on which there is a brown, oval, central area that usually is bordered with white. The brown spot looks like a saddle, and the green area looks like a saddle blanket; hence, the common name. It may exceed an inch in length and is stout-bodied. The primary nettling hairs are borne on the back of paired fleshy protuberances toward the front and hind ends of the body. There is also a row of smaller stinging organs on each side. This caterpillar feeds on many plants, including hibiscus and palms.

Puss Caterpillar

Puss Caterpillar (UF Photo)

The larva is convex and stout-bodied, almost 1 inch long when mature, and completely covered with gray to brown hairs. Under the soft hairs are stiff spines that are attached to poison glands. When touched, these poisonous spines break off in the skin and cause severe pain. Puss caterpillars feed on a variety of broadleaf trees and shrubs, and are most often found on oaks and citrus. In Florida there are two generations a year, one in spring and the other in fall. Natural enemies keep these caterpillars at low numbers during most years, but they periodically become numerous.

IO Moth Caterpillar (UF photo)

Io Moth Caterpillar

This is a pale green caterpillar with yellow and red stripes. It often exceeds 2 inches in length and is fairly stout-bodied. The nettling organs are borne on fleshy tubercles, and the spines are usually yellow with black tips. They feed on a wide range of plants, but ixora and rose are their favorite hosts.

Hag Caterpillar

Hag Caterpillar (UF photo)

This caterpillar is light to dark brown. It has nine pairs (sometimes fewer) of variable-length, lateral spines, which bear the stinging hairs. These spines are curved, twisted and likened by some to the disheveled hair of a hag, for which it is named. It is found on various forest trees and ornamental shrubs, but is not as common as the other stinging caterpillar species.

Less Well Known Venomous Caterpillars

Flannel Moth Caterpillar

Buck Moth Caterpillar

Spiny Oak-slug caterpillar (UF photo)

First Aid

Place clear tape over the affected area and strip off repeatedly to remove spines. Apply ice packs to reduce the stinging sensation, and follow with a paste of baking soda and water. If the victim has a history of hay fever, asthma or allergy, or if allergic reactions develop, contact a physician immediately.

Take-all Root Rot on Southern Turfgrasses

2014-06-26T16:46:00.000-04:00

This disease affects all species and varieties of southern turfgrasses including St. Augustinegrass, Bahiagrass, Cenetpedegrass, Zoysiagrass and Bermudagrass. The pathogen is naturally present on warm-season turfgrass roots. High rainfall and stressed turfgrass trigger the disease, and it is therefore observed during the summer and early fall months when Florida receives the majority of its rainfall. Any stress placed on the turfgrass can encourage or worsen the disease.

St, Augustine Roots Damaged by
TARR Fungus

This is a root rot disease. Because the roots are affected, they are not able to efficiently obtain water or nutrients from the soil, nor are they able to store the products of photosynthesis. Symptoms observed on the leaves are the result of pathogen activity on the root system. The fungus does not attack leaves.

Initial symptoms aboveground are irregular, yellow (chlorotic) or light green patches ranging in diameter from a few inches to a few feet. Roots are initially thin and off-white in color with isolated black lesions. Eventually, roots become very short, black, and rotted. Stolons and rhizomes may have black lesions and, under severe disease conditions, begin to rot. Entire plants may die, resulting in irregular patches of thinning grass, and if the rot is not controlled, bare patches may develop.

St. Augustinegrass Damaged by TARR Fungus

To minimize damage to the turf, stress factors need to be minimized by following Green Industries Best Management Practices recommendations (GIBMP). The turfgrass must be mowed at the correct height during the summer. Turfgrass should be mowed as frequently as necessary so that only one third of the leaf tissue is removed during any one mowing event. Scalping the grass damages the growing point.

Empire Zoysiagrass Damaged by TARR Fungus

Balance nitrogen applications with equal amounts of potassium. Use slow release fertilizer with equal amounts of slow release nitrogen and potassium - 16-0-16 for instance. Avoid nitrate-nitrogen products and quick-release urea products (e.g., uncoated urea). Extra potassium may be useful in late summer and early fall. When the disease is active, frequent foliar (leaf) feeding of all nutrients (N, P, K, and micronutrients) in small amounts is necessary if the root system is severely damaged; the roots do not function properly and are unable to obtain nutrients efficiently from the soil. As the fungus does well at high pH, do not apply lime to infected turf.

Azoxystrobin (Hertiage), myclobutanil (Immunox), propiconazole (Banner Max), pyraclostrobin (Insignia), thiophanate methyl (Clearys 3336), and triadimefon (Bayleton) can be used as preventative treatments. There are a few combination products available including Armarda (trifloxystrobin and tridimefon) and Pillar G (pyraclostrobin and triticonizole) which are more effective than single products. Keep in mind that these fungicides are not as effective as the use of cultural controls once the disease symptoms are observed. These fungicides are best used preventively, meaning they must be applied prior to symptom development. Start applying the fungicides at least one month prior to the time when aboveground symptoms are normally observed. Continue applying once a month until the weather is no longer conducive to disease development. These fungicides should be lightly watered into the root zone immediately after application.

Controlling Chinch Bugs in Your St. Augustine Turf

2014-06-20T14:00:00.000-04:00

Adult (with wings) and Pre-adult (without wings) Chinch Bugs

Many times a homeowner may treat his lawn for chinch bugs or have his yard professionally sprayed and assume the chinch bugs will be controlled. However, for various reasons such as resistance or poor application technique, damaging numbers are left behind. This leads many to the assumption that the problem is a fungus. To be sure the problem is chinch bugs, homeowners need to learn how to recognize these pests. There are many pictures of chinch bugs on my web site. You can use the soap flush method to find them. Make a soapy solution (1.5 ounces of dish soap per two gallons of water) and pour on a 2x2 foot suspicious spot. The soapy water will bring the chinch bugs to the surface in about five minutes or less.

Early Instar Nymphs Which are Pink With aWhite Strip

However, I think the best method to find chinch bugs is to get down on hands and knees in a suspicious spot, pull the stolons apart all the way down to the soil, and look for these little bugs. They are fast and small. Look in areas which are affected (not all green, not dead) and look in many locations. The adults are about 1/8 inch long, black with white wings lying flat on their back. The pre-adults are entirely back with no wings. Early instar instar nymphs are red with a white stripe across their back. If you belong to a homeowner’s association, perhaps two or three members could become the chinch bug experts. I am happy to help train these volunteers.

Chinch bugs are becoming more difficult to control as resistance has been reported to the widely used class of insecticides called synthetic pyrethroid products like bifenthrin (Talstar), permethrin, cypermethrin, deltamethrin, etc. I have heard frequent media advertisements lately for the product called Triazicide (gamma cyhalothrin) which is just another synthetic pyrethroid. When insect resistance develops to one product in a class of insecticides like the pyrethroids, then the resistance spills over to all products in the same class. A common homeowner product with bifenthrin is called OrthoMax Bug-Be-Gone and is commercially called (Talstar).

Chinch Bug Damage in Heavy Fertilized St, Augustinegrass
(right side of plot) versus normal fertilization (left
side of plot).

If you, as a homeowner, are buying your own product and applying it yourself and have had problems controlling chinch bugs for several years, then I suggest you buy a product with clothianidin (Arena). I would treat the whole section of the lawn which has had or currently has a chinch bug infestation. This product is available at some of the box stores as Green Light Arena and at John Deere Landscape Supply as just Arena. However, John Deere only has Arena in 40 pound bags – Green Light Arena at retail stores is in 12 pound bags and covers 4,000 square feet.

Be forewarned that over nitrogen fertilization will make your St. Augustinegrass much more attractive to chinch bug infestations. The above photo displays chinch bug damage on the right side of the plot which has been over fertilized with nitrogen. While the left side of the photo displays chinch bug damage to St. Augustine turf which has received recommended nitrogen rates. The chinch bugs obviously prefer heavy fertilized lush turfgrass. Not to say that they will not eventually move to the left side of the plot for greener pastures.

Kill Vegetable Garden Soil Pests With Summer Sun

2014-06-11T15:24:00.002-04:00

Introduction - Soil solarization is a practice used to manage weeds, nematodes, diseases, and insects in soil. The soil surface is covered with clear plastic, which allows sunlight to pass through and heat up the soil to temperatures that are lethal to many of these pests. If effective, solarization can reduce population levels of these pests for 3-4 months, sometimes longer.

Installation - The area to be solarized must first be cleared of existing weeds and debris. Tilling the site is helpful to increase penetration of heat into the top 6 inches of soil. Sticks, old roots, and other debris should be removed so they do not poke holes in the plastic.

Water helps to conduct heat, so best results occur if soil is moist but not waterlogged or muddy. If the soil is very dry and dusty, the solarization will not work as well. On sandy soils in Florida, the best conditions are when the soil received rain or irrigation the day before plastic is applied. If rain or irrigation occur just a short time before applying plastic, the soil can be heavy, muddy, or otherwise difficult to work with, and the clear plastic can get dirty.

At present, there are no recommendations about type or brand of clear plastic to use. Do not use black plastic or opaque plastic, which are readily available at the box hardware stores, because the soil will not reach as high a temperature as under clear plastic. Some people think thinner plastic is better, but maybe the main consideration is that the plastic should be strong enough to last for 6 weeks in the summer sun in Florida without breaking up.

The plastic should be stretched tight and the edges sealed completely by burying in soil. If edges are not completely sealed, heat will leak out and problems may result in these cooler areas. Some people recommend using two layers of clear plastic separated by spacers such as PVC pipe. This will create a buffer zone between the outer air and soil which keep soil temperatures higher, longer than a single sheet.

If the edges of the plastic come out of the ground, heat will leak out. It is important to re-bury or re-seal any exposed edges as soon as possible. Removal of a soil seal or damage to plastic will not ruin the solarization if it is caught quickly and repaired soon after it happens, preferably on the same day that the damage occurs.

The plastic should be left in place with all edges buried for at least 6 weeks. After that, the plastic can be removed, and if the procedure was successful, weeds and soil pests should be reduced for 3-4 months. Do not plant anything until the plastic is removed because the heat under clear plastic will kill seeds and plants! Disposal of used plastic can be a problem, especially if the plastic is not strong and breaks apart before or during removal.

Other considerations - A few small holes may not have much impact on solarization. However, duct tape can be used to seal small holes (< 1″ diameter). A small patch of duct tape will not affect heat conduction. Animals walking on plastic or birds pecking at the plastic can cause small holes that also can be sealed with duct tape. If the damage is extensive, the plastic may need to be replaced.

Suppose you want to cover a 10-ft-wide area and have strips of plastic only 5-6 ft wide. One possibility might be to lay the two strips side by side, overlapping in the center. However, overlap of plastic not sealed into the ground would allow a weak spot where heat could leak out. It is unknown if the two plastic strips could be sealed together successfully with tape, especially over a 6-week time period. A more reliable approach may be to seal both strips into the soil in order to have two solarized strips (each 4-5 ft wide) next to each other. But this would leave an untreated strip of soil between the two solarized strips where the edges of the plastic are buried

Raised beds are more work to prepare, but can be solarized. If water pools in low spots on the plastic, it should not be a problem as long as the water is clear, since light will pass through. But if there is dirt in the puddle it will block light, so dirt or soil in the puddle should be washed away or removed, especially if the area is large.

The edges of the bed may not receive direct sunlight if beds are positioned in an east-west direction. If the bed is positioned in a north-south direction, the east edge of the bed will receive direct sunlight in the morning and the west side will receive direct intense sunlight in the afternoon. On a bed that is positioned east-west, the top of the bed will receive direct sunlight through much of the day, but the edges may not receive much direct sunlight. As a result, the edges of the beds are cooler, and weeds may grow on the edges, particularly on the north side of the bed.

Solarization can greatly increase temperatures in the upper 4-6″ of soil. Deeper soil usually does not heat up enough to kill pests that are located there. So pests such as nematodes that are living deep in the soil will survive and eventually can move up into the solarized area. This re-invasion of the solarized soil usually takes about 3-4 months, so after that time the effects of solarization diminish. Solarization is best used for short-season crops. Pests may be reduced in a vegetable or ornamental crop planted right after solarization, but if another crop is planted immediately after that (double-cropping), the recolonizing pests and weeds may damage the second crop.

Do not bury drip irrigation tape or other irrigation plastic near the soil surface in a site to be solarized. The soil temperatures in excess of 120°F near the surface may melt some kinds of drip tape. Temperatures cool as we move deeper into the soil, so lines buried 6″ deep probably won’t be affected.

The temperatures that are lethal to pest organisms will kill beneficial organisms as well. Fortunately, beneficial bacteria and fungi seem to recolonize solarized soil quickly, so they can still break down organic materials and recycle nutrients if organic fertilizers are used.

Living With Sandhill Cranes

2014-05-19T15:41:00.001-04:00

Sandhill Crane (photo by Grant Sizemore)

Sandhill cranes are cherished members of the Florida ecosystem. They stand almost 4 feet tall, and their bugling or rattling calls are haunting and beautiful. Sandhill cranes occur in pastures, open prairies and freshwater wetlands in peninsular Florida from the Everglades to the Okefenokee Swamp.

Florida sandhill cranes are present in many urban areas and some unlikely places such as golf courses, airports and suburban subdivisions. This is probably due in part to the rapid development of their native habitat by humans. Cranes are probably attracted by the open setting (mowed grass) and availability of some foods (acorns, earthworms, mole crickets, turf grubs).

People inadvertently put them in harm's way when they attract these birds to their yards with feed. Some "feeding" is accidental such as when bird seed is spilled from feeders by other animals onto the ground below making a nice feeding station for cranes. But, some people deliberately feed sandhill cranes. In 2002, the Florida Fish and Wildlife Conservation Commission made it illegal to feed sandhill cranes (Florida Fish and Wildlife Code 68A-4.00(3)).

Why is feeding cranes prohibited?
Cranes fed by humans can become aggressive toward people. In several instances, children have been attacked by cranes. Cranes fed by humans also have been known to damage window screens and do other property damage. This behavior is probably a response of the birds to seeing their reflection, bringing out a territorial defense behavior (scratching at windows or shiny automobiles). Cranes also are more likely to tangle in human garbage in areas populated by people. Cranes are more likely to crash into power lines in urban areas where such aerial hazards are concentrated. Cranes attracted to people's yards for feed are put at risk as they walk across roads. Many sandhill cranes are killed each year on Florida roads (see photo). Attracting cranes to urban areas increases the threat of predation (especially to young cranes) by dogs or cats. Further, the cranes' diets, which normally are quite diverse, are disrupted when they eat one food item (such as corn), consistently. Heavy pesticide use in urban lawns also is of concern. Young sandhill cranes have died from pesticide poisoning.

Conclusion
It's never a good idea to feed wildlife. People inadvertently put cranes in harm's way when they attract these birds to their yards with feed. Florida sandhill cranes have an abundance of natural foods (insects and small animals) and they do not need handouts from humans. There are many reasons why cranes should not be intentionally fed by humans. For the good of the cranes, please do not feed them.

Three things you can do to better coexist in "Crane Country"

Never feed cranes and encourage your neighbors not to feed cranes. Cranes are less likely to inhabit urban areas if easy meals are not provided.
Cover or move automobiles so that cranes cannot see their reflections in the shiny surfaces. Windows or glass doors that the cranes attack can be temporarily covered with material so that the birds do not see their reflections.
Temporarily cover windows or screens. A string mounted on stakes about 2.5 feet off the ground will provide an exclusion "fence" around the parts of homes (window or pool screens) that are being damaged by cranes.

Accept some digging for food. Cranes sometimes damage lawns and gardens as they dig for food such as mole crickets and beetle grubs. The birds, in this case, provide natural "biological control" of these common pests of turf.

The above is a publication prepared by the Florida Fish and Wildlife Conservation Commission.

Love Bugs

2014-04-30T11:29:00.000-04:00

Adult Love Bugs

We seem to be currently having our semi-annual infestation of love bugs. These little pests are actually flies in the family Bibionidae. They were reported in Louisiana in the 1920’s and by the 1940’s had invaded Florida. It was erroneously reported that love bugs were introduced into Florida by the UF and USDA entomologists. However, love bugs were well established in Florida before any research was conducted. There is clear documentation on the movement of this pest around the Gulf Coast and into Florida. This fly was first collected in Escambia County, the western most county in Florida, in 1949. It has now spread all over the state.

Love Bug Larvae

Two flights occur each year. The spring flight occurs in late April and May and the second flight occurs in August and September. Flights extend over periods of 4-5 weeks. Mating takes place almost immediately after the emergence of females. Adult females live only 2-3 days and feed on nectar of various plants. Love bugs are attracted to irradiated exhaust fumes (gas and diesel fumes exposed to sunlight) at temperatures above 83 degrees F. (usually between 10:00 a.m. and 4:00 p.m.). Also, hot engines and the vibration of vehicles apparently contribute to the attraction of love bugs to highways.

Females may lay as many as 350 eggs which are usually deposited on decaying plant material. Larvae feed on the decaying plant material and live on the soil surface just beneath the decaying organic matter. The larvae are often found in pastures under cow manure. They perform a beneficial function, because they convert plant material into organic components which can be used by growing plants.

There isn’t any practical way to control love bugs with insecticides in large areas. However, smaller areas around a home could be sprayed with a registered insecticide. Love bug numbers have been somewhat reduced in recent years by predators such as birds and armadillos, and invertebrate organisms such as earwigs, beetle larvae and centipedes. There are a number of fungi which also can appreciably reduce larvae numbers. In spite of all of the natural controls, they still are a real nuisance.

There are several options available to lessen the problems facing motorists. By traveling at night motorists can avoid love bugs as they do not become active until mid-morning. Screens can be placed in front of the radiator to block incoming adults. Also, deflector shields placed at the front of the hood help reduce the number of adults impacting on the windshield and upper front finish.

Splattered bugs should be washed off the car as soon as possible. Love bugs are more easily removed, and the chance of damaging the finish on the car is lessened, if the car has been waxed recently. When the remains are left on the car for several days, the finish will often be permanently damaged. This is because the bodily contents of love bugs is somewhat acid and the acidity will increase through bacterial action over a period of a few days. Auto paint has been improved over recent years which has lessened this problem. Soaking the area for several minutes will ease removal. When love bugs are numerous, some motorists spread a thin layer of baby oil over the front of the hood, above the windshield and on the grill and bumper. This practice will make removal a simpler task.

Sawflies - What Are They?

2014-04-08T15:06:00.001-04:00

Recently, a homeowner reported what appeared to be an insect infestation on a tree at her home in southwest Lakeland. She indicated that this infestation had occurred for the last 7-8 years in March and the tree was usually defoliated. I thought oak tree caterpillars, but the homeowner said definitely not an oak. She further indicated that the larvae were everywhere - on the tree, falling out of the tree to the ground and in her hair, crawling up the house, on trash cans, and on her other landscape plants. This all seemed very unusual and required investigation!

Blackheaded Ash Sawfly Larvae

I visited the homeowner and saw the tree and the infestation – the tree was pretty much white with these caterpillar-like creatures. I thought this insect was a sawfly, but didn’t know which one and could not identify the tree. With the help of the Forest Service and the UF Department of Entomology, the tree was identified as a white ash (not common in Polk County) and the bug as a blackheaded ash sawfly. I had not seen the bug or the tree in Polk County before. This huge infestation had been occurring on this single homeowner tree for the past seven years. Apparently this white ash was able to withstand the repeated injury.

Infested White Ash Tree

So, what are sawflies? They are not flies at all, but are a primitive group of insects in the wasp, ant and bee order – Hymenoptera. The adult sawfly looks nothing like adult moths and butterflies as they are wasp-like, often brightly colored, and are usually found on flowers searching for host plants, mates or prey - some adults are predators. The sawfly larvae are quite different from the typical bee or wasp larvae which are grub-like. Sawfly larvae look like moth or butterfly caterpillars at the first glance as they all have leg-like structures on the abdomen called prolegs for locomotion. However, moth and butterfly caterpillars have not more than five pair of abdominal prolegs with crochets (hooks) for grasping while sawflies have six or more pair of prolegs which do not have crochets. So, sawflies are pretty easy to distinguish from moth and butterfly larvae.

Control of this infestation for the homeowner probably will be quite difficult. The tree could be sprayed with a conventional insecticide in March to control the larvae, but this treatment would be quite expensive – probably not an option for the homeowner. A possible treatment in this case is a fall application of a systemic insecticide like Bayer Advanced Tree and Shrub Insect Killer. Making the application in the fall would give the chemical time to translocate into the upper branches and foliage of the tree by spring-time. The larvae hopefully will then die after feeding on the foliage. No guarantee that this systemic treatment will work. Keeping the area under the tree clean may also help reduce adult numbers in the spring and reduce the infestation.

Blackheaded Sawfly Larvae Clustered on Trunk

Blackedheaded Sawfly Larvae on Understory Plant

Citrus Greening - What's a Homeowner To Do?

2014-04-04T15:50:00.000-04:00

Citrus Greening is a disease transmitted to all varieties of citrus and some ornamentals (i.e. box orange and orange jasmine) in the Rutaceae family by a little insect called the Asian Citrus Psyllid (ACP). The insect was first found in Florida in 1998 and the disease, which is a bacterium, was discovered in residential trees in south Florida in 2005. The insect and the disease occur in citrus production areas all over the world and now occur in most if not all citrus production areas in the United States and Florida. The disease is present in most commercial groves and probably in most if not all homeowner citrus trees. Commercial growers in Florida are struggling to control this disease. Chemical control of the psyllid and removal of infected trees are the only methods currently available to growers to manage the spread of the disease.

How would a homeowner determine if his tree is infected? Symptoms can be found year round but are most common September through March (see below). The tree may remain symptomless for some time after it has acquired the disease. Symptoms include vein corking, fruit remain green at blossom end, leaves with yellow veins, reduced fruit size, yellow shoots, fruit and leaf drop. Blotchy mottle in leaves is a key early diagnostic symptom. The tree will gradually decline and the juice will become bitter and of no value. The tree will decline over a number of years and may eventually die.

Is there some treatment to help control this disease? There are no specific treatments for control of this disease in the home landscape or in commercial groves. If a homeowner does decide to plant a citrus tree, then it would be best to treat the soil around the tree with a systemic insecticide at planting like Bayer Advanced Citrus, Vegetable and Fruit Insecticide with imidacloprid. This treatment may control the psyllid and prevent greening infection while the tree is relatively small – 8 or 9 feet tall however, this treatment may not be effective for preventing greening infection in large mature trees.

It has been found that very healthy trees in commercial groves are able to live with the disease and be productive for a longer time than unhealthy trees. So we encourage homeowners to closely follow fertilization recommendations and make sure the tree has ample water during periods of low or no rainfall to minimize tree stress. As the greening bacterium blocks off the phloem preventing nutrient transfer to the leaves from the roots, we recommend making 2-3 foliar applications of micronutrients at full leaf expansion during leaf flushes in the spring, summer and late summer/fall. The application of horticultural oils, like Volck Oil, to control sucking insect infestations will also help minimize tree stress.

Are there any on-going non-invasive research projects for control of greening which might have homeowner application? The USDA at Ft. Pierce is currently conducting experiments using heat treatments to kill the greening bacteria in infected trees - this is intended for commercial use at this point? I don't, at the moment, see how this could be done on a commercial scale, but it might have homeowner application. A possible scenario would be to cut the tree back to a few feet off the ground then cover and apply heat to a specific temperature. However, there are many questions to be answered. What kind of tree cover to use and what type of heat source? What temperature is needed and for how long - the temperature would need to be high enough to kill the bacteria and not damage the tree? How often would some type of heat treatment be needed? A greening infected tree has the bacterium in the roots, so how fast would the upper growth be infected from the roots? And what is the potential for re-infection by wild psyllids. The USDA Lab in Ft. Pierce is offering a workshop on April 30th which I plan to attend.

Until reliable control options become available to homeowners we recommend planting some other type of fruit – there are many to choose from including pomegranate, fig, blueberry, peaches, plums, nectarines, blackberries, and many more.

Adult Asian Citrus Psyllid Feeding on Citrus Tree Leaf

Differential Fruit Size

Typical Blotchy Mottle

Color Break - Fruit Green at Blossom End

Yellow Veins

Yellow Shoots

Fertilize Your Lawn Now

2014-04-03T09:06:00.000-04:00

If you have not fertilized your turf then now is the time to make the first application of the year. Selecting a fertilizer is the first step. Most of the retail garden centers should have a product which will fit your needs. When you look at the fertilizer bag you will see three large numbers on the front of the bag. The first number stands for percent nitrogen (N), the second stands for the percent phosphorous (P) and the third stands for percent potassium (K). In other words if the product is a 16-2-16 then a 100 pound bag would have 16 pounds of nitrogen, 2 pounds of phosphorous and 16 pounds of potassium. The other 66 pounds consists of some sort of filler like sand. You have probably noticed that the middle number which represents phosphorous is quite low. The reason for this is that most soils in central and north Florida have an ample amount of phosphorous already in the soil. Adding addition phosphorous is usually not necessary and can easily runoff into our waterways encouraging exotic plant growth.

We recommend selecting a turf fertilizer which has nitrogen in a 1:1, 2:1 or a 3:1 ratio with potassium (third number) and 30-50% slow release nitrogen. Acceptable products include Scotts Turf Builder for Southern Lawns (32-0-10) which has 50% slow release nitrogen, and a 3 to 1 nitrogen/potassium ratio; and Lesco 24-2-11 fertilizer which contains at least 50% slow release and has 2:1 nitrogen/potassium ratio. It is important to have no less than a 3:1 nitrogen/potassium ratio as potassium is important for building strong roots which increase turf tolerance to stresses. There are other acceptable products on the market, but space prevents listing any more. And there are more inexpensive products available which have a greater than 3:1 nitrogen/potassium ratio such as one sold locally with a 29-0-4 ratio which we don’t recommend due to low potassium.

You will find stacks of weed and feed products at the retail garden centers right now. We do not recommend weed and feed products because weed killer applications should be made in mid-February to be most effective followed up with a second application before April 15^th. Mid-February would be much too early to apply a turf fertilizer in a weed and feed product since most turfgrass is still somewhat dormant at this time. Fertilizer applied in mid-February has the potential to leach and run off into our waterways during a substantial rain event. The correct time to apply turf fertilizer in central Florida is at the end of March. However herbicides in a weed and feed product applied at this time would be applied too late to control many germinating weeds. So, weed killers should be applied in mid-February with a second application before April 15^th and fertilizer should be applied at the end of March to be most effective and Florida-Friendly.

Let’s say that you have selected the Scotts Turf Builder for Southern Turfgrasses (32-0-10) or the Lesco 24-2-11 for your lawn fertilizer. The next question is how much to apply? The University of Florida and Polk County require that not more than one pound of nitrogen be applied per 1000 square feet of turfgrass per application if the product has 30-50% slow release nitrogen and 1/2 pound nitrogen if the product has less than 30% slow release nitrogen.

You have these bags of formulated fertilizer (32-0-10) and (24-2-11) so how much of the product in this bag equals one pound of nitrogen. This can be calculated by dividing 100 by the percent nitrogen in the bag (32% and 24% nitrogen) – 3.3 pounds of the 32% nitrogen product and 4.2 pounds of the 24% nitrogen product equals one pound of nitrogen. A 50 pound bag of the 30% nitrogen product will cover about 15,000 square feet of turfgrass and a 50 pound bag of the 24-2-11 will cover about 12,000 square of turfgrass applied at one pound of nitrogen per 1000 square feet of turf. Applied at 1/2 pound nitrogen the bag would cover twice the square footage - 30,000 and 24,000.

Next you are going to have to determine how many square feet of turfgrass you have in your landscape. Square feet is determined by multiplying width by the length. A tape measure or roll-a-tape would be handy tools to help make this calculation. Let’s say your front turfgrass is an area which is 150 feet long and 35 feet wide. Thirty-five multiplied by 150 equals 5250 square feet of turf area. The correct amount of 30-0-10 product for 5250 square feet calculates out to be 17 pounds based on the product being applied at 3.3 pounds per 1000 square feet. (3.3 pounds 30-0-10 X 5250 square feet turf divided by 1000 square feet =’s 17.3 pounds.)

Next you will need to calibrate the output of your rotary spreader. We have already determined that 3.3 pounds of 32-0-10 fertilizer needs to be applied per 1000 square feet to equal one pound of nitrogen per 1000 square feet. An area smaller than 1000 square feet needs to be selected to practically calibrate the spreader. Lay out a small area something like 200 square feet, an area 10 feet wide (assuming the spreader throws five feet to each side) and 20 feet long, and cover with plastic. This area would require 1/5 (0.2) of the recommended fertilizer for 1000 square feet or 3.3 pounds divided by 5 which equals 0.66 pounds. Set the spreader output level at a medium opening. Fill the spreader half full with fertilizer and pass over the 200 square foot area. Pour the expended fertilizer from the plastic sheeting into a container and weigh. Adjust opening until 0.66 pounds is expended per pass over the 200 square feet test area. It may be a good idea to calibrate the spreader at 1/2 the above rate and cover the turfgrass twice in different directions to minimize missed areas.

Lubber Grasshoppers

2014-03-28T10:48:00.001-04:00

Now is the time of year to be on the lookout for lubber grasshopper nymphs. The eggs that were laid by adult females last summer are now beginning to hatch. The nymphs are black with a yellow/orange strip running down their back and are about ½ long. As they emerge from the soil they will stay grouped together for a day or two before spreading out to various landscape plants. Their favorite plants are various type of lilies, but they will feed on most plants in the typical landscape. They grow quickly and by June/July will reach an adult size of three inches or so. They cannot fly well as they have shortened wings so they kind of crawl, hop and beat their wings. They can move around surprisingly well

Lubber grasshopper nymphs just
emerged from the soil

They usually are not present in large numbers, but during certain years specific locations can experience very large and damaging numbers. Several years ago there was a heavy infestation south of I-4 along State Road 557 and 557a. These large grasshoppers consumed most of the plants in homeowner landscapes along 557a. Fortunately numbers declined after a year or two and have not again reached those huge numbers. During that same time Infestations in the south and central part of Polk County were relatively small.

When they reach adulthood in early to mid-summer, insecticide sprays are not effective. At the moment they are just beginning to hatch and emerge from the soil. For the next few weeks homeowners need to be watchful and spray these emerging nymphs with either Seven or Ortho Max Bug-Be-Gone Insecticide with bifenthrin. If you choose not to spray, pick up the nymphs and and dispose of them. They are not very fast and can be caught by hand and dropped in a jar of soapy water where they will sink and drown. The adult are also pretty easy to catch and can be killed by hand or foot. Make sure you carefully look over your plants regularly for these pests. Be sure to track down and kill any that you see in your landscape.

Cottonmouth Snakes

2014-03-27T14:26:00.000-04:00

Juvenile Cottonmouth Snake

Most people are familiar with adult Cottonmouth snakes which occur in every Florida County and are quite venomous. Young or juvenile Cottonmouths are marked with broad, splotched bands that fade with age, and have tails tipped with mustard yellow. Juveniles may be misidentified as Copperheads which are only found in Florida in a small area of the panhandle. Their thick body is reddish brown to dark gray-brown; older individuals may be nearly solid black - typically what most people see in the wild. Dark bands run from each eye to the corners of the jaw. When threatened, it may coil and open its mouth wide, showing the cottony white interior. This snake gives birth to live young and does not lay eggs as is true of other venomous snakes in Florida.

They are usually found in or near aquatic habitats including ponds, lakes, streams, rivers, canals, ditches, cypress swamps, wet prairies, and brackish costal marshes. They may be especially abundant in areas where wading birds congregate. They are occasionally encountered in upland habitats away from water. They feed on fish, snakes, turtles, young alligators, birds (and their eggs), mice, rats, squirrels and rabbits.

Keep in mind that these venomous snakes, including Rattlesnakes, Cottonmouths and Coral snakes are all over the state of Florida and can end up in a home landscape. Most of the time snakes in home landscape are non-venomous. However, homeowners need to be prepared in the very unlikely event of an undesirable encounter with a venomous snake. Documents on dealing with venomous snakes can be found on Dr. Steve Johnson's website: http://ufwildlife.ifas.ufl.edu/dealing_with_snakes.shtml

Brown Recluse Spiders Rare in Polk County

2014-03-04T08:38:00.001-05:00

What do brown recluse spiders look like? The males and females are about the same size. The body, including the legs, is a little wider than a quarter dollar coin. They have a series of markings on the head and thorax, which look like a violin with the base pointing toward the head. The brown recluse has six eyes arranged in pairs. The male Southern house spider is often confused with the brown recluse, as it has the violin coloration on the head and thorax; however, it has eight eyes all clumped together in the middle of the head rather than six.

Another common spider found around the home is the brown widow, which is quite venomous. However, it is not aggressive and seldom bites. They are easily differentiated from the brown recluse because they have a yellow-red hourglass on the bottom side of the abdomen and the egg masses have spines sort of like those of a sand spur.

The brown recluse spider, Loxosceles recluse, is frequently reported in Florida as a cause of necrotic lesions in humans. For example, in the year 2000 alone, the Florida Poison Control Center reported nearly 300 alleged brown recluse bites in the state. Ninety-five of these bites were reported in Central Florida under the jurisdiction of the regional poison control center in Tampa. As a matter of fact, a large number of brown recluse bites are reported every year in the Tampa area. In addition, every year I have numerous clients here at the Polk County Extension Office who report to me that they have been bitten by brown recluse spiders.

In spite of all these reports of bites, not one brown recluse spider has been recovered in the Tampa Bay area, including Polk County, other than the Chilean brown recluse spider, which was found in a house in Winter Haven a few years ago. Those spiders were believed to have come in with some building materials.

So, the question is what is causing the necrotic lesions in people in Florida, if it is not brown recluse spiders. Brown recluse bites cause clear necrotic areas in the skin. If an inflammatory core lesion exists, necrotizing infection should be anticipated, not a spider bite.

A number of other arthropods and an assortment of diseases, some caused by micro-organisms such as flesh-destroying bacteria, and some with other causes, are known to produce necrotic or apparent pre-necrotic wounds. These wounds could be tick-induced, viral, bacterial, fungal or caused by a blood disorder, cancer, a reaction to drugs, chemical burns or an underlying disease such as diabetes. Some wounds just can’t be explained. For more information, visit my website at http://polkhort.ifas.ufl.edu and click on A-Z publications where you will find a circular entitled “The Brown Recluse Spider”.

Termites

2014-02-27T13:33:00.000-05:00

This is the month when you may begin to see evidence of termites in or around your home. People often have trouble distinguishing termites from ants. There are however, distinct differences. Termites have two sets of equal size wings, beaded antennae and the abdomen is broadly joined to the thorax. Ants have elbowed antennae, two sets of different size wings and the connection between the abdomen and thorax is constricted.

Subterranean termites - There are many species of termites, but you only need to be concerned with two general types – the dry wood termite and the subterranean termite. At this time of the year, you may see swarms of subterranean winged adults both indoors and outdoors. They select a mate, fall to the ground and search for a site in the soil to start a new colony. The male and female adults remain together for many years with the female laying thousands of eggs. Subterranean termites are present in most residential landscapes. The presence of the little white worker termites in mulch, in rotting logs or swarming adults outside of your home does not necessarily mean that they will eventually infest your house, but of course it is possible. However, if you see winged adults flying in your house, then you probably have an infestation which will need treatment.

Termite infestations need to be treated by a professional. Call 2-3 reputable companies for a free inspection. If you have questions call the Extension Office. Left untreated, a large subterranean colony can eat up to one pound of wood per day – 365 pounds per year. There are excellent soil insecticide and bait treatments available for control of subterranean termites. This treatment should give your house five or more years of protection from termites. Be sure to ask the company about the warrantee.

Drywood termites - Drywood termites will infest dry wood as the name implies and are not associated with soil and only need minimal amounts of moisture which they readily find in rafters. They exist in separate small colonies and are not as destructive as subterranean termites; however lack of treatment can lead to serious structural problems. They also have mating flights like subterranean termites. The mated pair search for suitable wood to infest which might be another rafter in your attic.

The treatment for drywood termites is altogether different from subterranean termites as the infestation is an aerial one not associated with soil, so it is critical to identify the winged adults or the type of damage. An identifying characteristic of drywood termites is the presence of fecal pellets which they push out of the infested wood. The pellets are small (not powder-like), can be different colors from red to white depending on the wood, and have indentations on the sides. If you are unsure of the type of infestation you have, bring a sample to the Extension Office and I will examine it.

The treatment of choice is tenting in which the structure is enclosed in a plastic tarp. After the tarp is secured over the house, a volatile gas is pumped into the structure. The gas penetrates the wood and kills the termites. There is no residual with the gas treatment, so future re-infestation is possible. There are other less expensive treatments in which the suspected wood is drilled and an insecticide is injected into the void occupied by the termites. The problem with the drilling treatment is that colonies can be missed.

What can you do around your home?

· Do not leave wood scraps lying around your yard.

· Do not place mulch up against your foundation – any type of mulch as this increases the capacity of the soil to hold moisture.

· Repair leaky hose bibs.

· Direct sprinklers away from the house.

· Stucco or veneer exterior finish should be 6-8 inches above grade so you can see mud tubes. Subterranean termites will travel up from the soil behind stucco and veneers and on into the house.

· Do not disturb soil around foundation as this may impact previous termite treatments.

· Watch for drywood termite fecal pellets.

· Repair screens and caulk cracks and crevices in structure.

· Keep shrubs at least 2-3 feet away from foundation – termites will travel under foundations following tree roots.

Written by
David Shibles
Urban Horticulturist
Polk County Extension Service