Insects

Fire Ants: What Happens to Them in a Flood?

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Fire Ants: What Happens to Them in a Flood?
CT Scanning Shows how Fire Ants Interlock to Form Floating Rafts – Entomology Today, June 12, 2014

Flooding has been a problem in central Texas and occasionally in parts of Georgia. Floods impact fire ants, but perhaps not like we would wish or think!

Following info from Urban IPM blog by Wizzie Brown, Texas A&M Entomologist.

Red imported fire ants live in the soil.  What happens to them when we have flooding?  Many people may think that they will drown in the flood water.  Unfortunately this isn’t true.

Floating Fire Ants

When fire ant colonies are flooded, the ants form living rafts by clinging together.  They float along the water surface until they hit dry ground, a tree, rock or other dry object.  Once they come into contact with a dry area, they emerge from the flood waters and take shelter anywhere possible until they can re-create a colony in the soil.  Living rafts of fire ants can take on different shapes from long ribbons to mats to a ball of ants.

Any floating mats of fire ants that are encountered should not be touched or disturbed.  Do not touch them with sticks or other objects as the fire ants will quickly grab onto the object. If working in flooded areas, make sure to wear appropriate clothing.  Long sleeves, pants and gloves will create more of a barrier against fire ants reaching skin where they will bite and sting.  Be aware that fire ants could be hiding anywhere that was flooded.  Wear gloves when picking up debris or other objects.  You may want to spray insect repellent containing DEET on your shoes and pants.

If you encounter fire ants in debris, use a fast-acting contact pesticide labeled for ants, but make sure the products are not sprayed into water as they can be toxic to aquatic organisms.  Fire ant baits should not be used after flooding because many of them are slow acting and colonies will be disorganized and not foraging for food.

Also be aware that fire ants may be showing up in areas that may have not had them previously or areas that were treated.

Gloomy Scale Crawlers are Active and Vulnerable

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Gloomy scale crawlers are active and vulnerable
Adult gloomy scale, Photo – SD Frank, EcoIPM

Info taken from the EcoIPM website and the SE Ornamental Horticulture & IPM website

Gloomy scale

Gloomy scale, Melanaspis tenebricosa, is an armored scale that feeds on maples and other tree species. It becomes very abundant on red maples on streets and in landscapes and can cause branch dieback and tree death in some cases. It is not unusual to find trees with nearly 100% of their trunk covered in scale. Street trees are particularly prone to gloomy scale. Crawlers of this scale are active now and can be seen on bark and under scale covers. One of the reasons we have found this to be such a pest is that female gloomy scales produce about 3 times as many eggs when they live on relatively warm trees (like in a parking lot) than when they live on cooler trees (like in a shady yard). This amazing work is outlined in a recent paper by Adam Dale.

Control of this scale is complicated because crawlers emerge over 6-8 weeks so it is impossible to treat all the crawlers at once with horticultural oil or other contact insecticide. This is different than in other scales, such as euonymus scale, in which all crawlers are produced within a narrow window of 2 weeks or so. Adam Dale took a video of some gloomy scale crawlers so you can get an idea of how tiny and nondescript they are. This may also give you an idea of why scales are so vulnerable at this stage to the environment, predators, and insecticides like horticultural oil. Once they produce their thick waxy cover they are much less vulnerable to all these factors.

See video of gloomy scale crawlers (immatures).

Read the original article.

Bagworms: What are these things hanging in my trees?

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Bagworms: What are these things hanging in my trees?

Bagworms: What are these things hanging in my trees?

Bagworms

Info taken from the publication Control of Common Pests of Landscape Plants by Tim Daly, Gwinnett County Cooperative Extension Agent and Beverly Sparks & Will Hudson, Extension Entomologists.

Bagworms construct and live inside a 1- to 2-inch long tough, tear-shaped portable silken case. These bags are the insect’s most easily seen and identifiable feature. Outside, the silken texture of the bag is somewhat concealed with layers of leaf, twig and bark fragments. The bag has an opening at the larger end that allows the worm to partially crawl out to make repairs to its bag and eat.

Bagworms attack broadleaf and coniferous trees and shrubs. Here are some control measures.

  1. Follow proper watering, fertilizing and pruning practices.
  2. Remove other stress factors from trees when possible.
  3. Infested plant material cannot be treated and should be removed and disposed of.
  4. Protect trees from infestation or reinfestation by using products containing bifenthrin or permethrin. Make first application in April and subsequent applications in late May, mid-July and late August.

To find more ID and control information on this or other landscape insects read the UGA publication Control of Common Pests of Landscape Plants 

To find pesticide recommendations and use information visit the Georgia Pest Management Handbook.

Sawflies are a common rose pest this spring

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Sawflies a common rose pest this spring
Sawflies are a common rose pest this spring
Rose sawfly, University of Delaware website

Edited from this article by Paul Pugliese, the agriculture & natural resources agent for the University of Georgia Extension office in Bartow County

A common rose problem this year is injury caused by rose sawflies, also known as rose slugs.

These insects do not discriminate on the types of roses on which they feed. Even ‘Knock Out’ roses make a tasty meal for these critters. Home gardeners often ask why ‘Knock Out’ roses are affected if they are supposed to be problem-free. These roses are bred for resistance to certain diseases, like black spot, but are still damaged by a variety of rose-loving insects.

Sawfly larvae

Sawfly larvae look similar to the caterpillar stages of moths and butterflies, but have six or more pairs of prolegs behind the three pairs of true legs on their body. True caterpillars have fewer prolegs.

Caterpillars can also affect roses in the spring, but the damage they cause is slightly different. Caterpillars chew large holes in the leaves. Sawfly larvae chew a thin layer off the surface of leaves, leaving a skeletonized appearance.

If you hold up an affected leaf, you can see light shining through it. This unique “window pane” damage is a classic sign of sawflies. If you look carefully, you might even find a few, tiny, slug-like larvae on the leaves.

Sawfly damage

Some sawfly species can chew holes through the leaves as they get older, but usually you will see both types of damage on the same plant. Sawfly larvae eventually become small, non-stinging wasps that feed on other insects.

Begin scouting for sawflies in April or early May. Most sawfly species feed through June and will not return again until next spring. The larvae are often found on the undersides of the leaves, so inspect both sides of the leaves carefully. Keep in mind that the damage caused by sawflies is only to the leaves and mainly affects the appearance of the plant. Plants that are otherwise healthy can tolerate significant feeding damage and will usually put out new leaves by mid-summer.

Sawfly control

Sawflies are best controlled when they’re young. You can simply pick them off by hand. A forceful spray of water from a hose can also knock off sawflies. Once dislodged, they cannot climb back onto the plant.

Synthetic insecticides that control sawflies include acephate (Orthene), carbaryl (Sevin), malathion and various pyrethroids. Avoid using insecticidal dusts and spraying flowers, as many insecticides are highly toxic to bees and other pollinators.

Imidacloprid (Bayer Advanced), a systemic insecticide, can be applied to the soil around the roses in spring before feeding activity is noticed. However, once the damage is noticed, it is usually too late for a systemic product to be effective.

Bacillus thuringiensis (Bt) products are effective against leaf-feeding caterpillars, but not on sawflies.

For more answers to gardening questions, contact your local UGA Extension office at 1-800-ASK-UGA1 or search UGA Extension publications at extension.uga.edu/publications.

Spring is a good time to manage Azalea Lace Bugs

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Source – Will Hudson and Kris Braman, UGA Extension Entomologists

azalea lace bug and leaf injury
Azalea lace bug and injury, Pest and Diseases Image Library, Bugwood.org

Azalea lacebugs overwinter as eggs and hatch in the spring. Early spring is a good time to control them before they become too numerous.

Azalea lace bug attacks azaleas and some rhododendrons. Azalea lace bugs mainly feed on the undersides of the leaves, leaving the top of the leaf with white to yellow stippling or flecking. Heavy lace bug feeding on azalea can reduce plant vigor and flowering and affects the overall look of the plant.

Adult azalea lace bugs are 1/8 inch long. The transparent wings are held flat on the back. Their wings are lacy with two grayish-brown cross-bands connected in the middle. Nymphs begin life clear but quickly turn black and spiny. The flask-shaped eggs are partially embedded in leaf tissue, usually on the bottom of the leaf, and often are covered with a black tar-like secretion.

Look for the first signs of damage on plants in full sun or in protected areas beginning in March and continuing throughout the summer. Lace bugs overwinter as eggs. There are four generations a year. Lace bug adults and nymphs live and feed on the underside of leaves. Look for white stippling on older leaves. Look under leaves to find lace bug life stages and black fecal spots. On azaleas with a lot of damage, the top of the leaf can become grey or silvery.

Azaleas can withstand a lot of lace bug injury without much reduction in growth or bloom. The damage however on the leaves is unsightly. Control is generally recommended for the spring when insects are few in numbers. Treating early also protects the new leaves from damage from these insects. Once a leaf is damaged, the injury will be visible until the leaf falls off the plant.

Time spring insecticide applications for the presence of the first generation nymphs, usually with the early warm weather in late February in south Georgia through March and April in central and north Georgia.

Late summer insecticide applications are also helpful. Lacebugs overwinter as eggs and managing adults now reduces the number of eggs on plants and the number of lacebugs you will see next spring. Once lacebugs are in the egg stage, insecticides will not effectively manage them.

Cultural controls for azalea lace bugs

  • Plant azaleas only in partial shade. Too much sun stresses the plant and can make lace bug injury worse.
  • Keep plants healthy with proper planting, fertilizing and watering.
  • One of the best things you can do is scout azaleas (particularly early in the season) to identify and control infestations before numbers increase and leaf damage is severe.

Chemical Controls

Contact insecticides include the pyrethroids (bifenthrin, cyfluthrin, cypermethrin, permethrin, etc.) and carbaryl (Sevin and others) as well as other insecticides.

  • The biggest concern with contact insecticides is getting full coverage. The chemical must be applied to the underside of the leaves. This is difficult with larger, fuller plants.
  • You may need to make more than one application for full control. Check plants three to four weeks after the first application to see if they need another treatment. Knocking the branches over a white piece of paper should dislodge the lace bugs and make them easier to see.

Systemic insecticides

  • Some systemic insecticides may be used as soil applications (liquid drenches and granular treatments) as well as sprays. Soil applied insecticides enter through the root system and then travel into the leaves.
  • Foliar sprays of systemic insecticides tend to work more quickly than soil application but soil applications give a longer residual control – up to several months.
  • Even though some soil applied systemic insecticides may take two weeks or longer to become active in the leaves of large plants, this is not a problem if plants are small or if application is made early enough in the season to provide protection for the first flush of new leaves.
  • Read and follow all label directions since systemic insecticides differ in the way they work in the plant.

 

For more information:

For pest management information see the Pest Management Handbook (Follow all label recommendations when using any pesticide)

Contact your local Extension Agent at (800) ASK-UGA1 or locate your local Extension Office at http://www.caes.uga.edu/extension/statewide.cfm

Control of Lace Bugs on Ornamental Plants

Get updated on fire ant baiting

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Get updated on fire ant baiting

Article written by Mike Merchant, Texas A&M Agrilife Extension Entomologist, in his blog Insects in the City

Fire ants remain the most prevalent outdoor ant pest in most areas of the southern U.S.  Throughout the U.S. we estimate the annual cost of fire ant control at over $6 billion.  But the cost of this pest goes far beyond measurable dollars.  Fire ants reduce the recreational value of our parks and backyards, disrupt wildlife populations, and send thousands to emergency rooms each year from their painful stings.

So as we get ready to enter fire ant season, it may be a good time to bring yourself and your staff up to speed on fire ant control. Many people are surprised to learn that fire ants are not an especially difficult pest to manage, once the biology and control tools are understood.

One of the best places to learn about fire ant management is the eXtension fire ant website, a place where the best information about fire ant is assembled by Extension agencies throughout the South. This information was recently summarized and presented in an informative webinar by Dr. Fudd Graham, fire ant specialist with Auburn University.   Dr. Graham focuses on fire ant biology and use of baits for fire ant control.

It’s worth knowing something about how fire ant baits work because they are the most economical, ecologically friendly, and effective control methods for fire ants. The webinar will provide you or your technician with an hour of training that should pay for itself many times over.

 

Mike Merchant is an entomology specialist for Texas AgriLife Extension. He works with pest management professionals, school facilities managers, extension volunteers, researchers and other extension professionals. His areas of specialty center on research on insects affecting man including spiders, scorpions, fire ants, termites and others. His program also focuses on training school maintenance professionals in principles of integrated pest management (IPM). His goal is to make schools healthier, cleaner places to study and live.

Ambrosia Beetles begin flying in Jan and Feb!

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Will Hudson, UGA Extension Entomologist

 Asian or granulate ambrosia beetles are tiny (<1/8″) wood-boring insects that attack the trunks of young and weakened trees and shrubs. Ambrosia beetles tunnel into stems and construct galleries where they raise their young. Beetles carry on their bodies a fungus that grows in these galleries producing ambrosia which feeds both adults and larvae. Ambrosia beetles can also carry the spores of disease pathogens that infect the tree. The growth of these fungi can lead to weakening or death of the tree.

Ambrosia beetle sawdust 'toothpicks' - Byron Rhodes, UGA, Bugwood.org
Ambrosia beetle sawdust ‘toothpicks’ – Byron Rhodes, UGA, Bugwood.org

As ambrosia beetles tunnel, they push sawdust out through their entry hole. This sawdust can cling together forming short ‘toothpicks’ sticking from the infested stem. These toothpicks make it easy to identify ambrosia beetle attacks.

Wind or rain may destroy these toothpicks leaving just the small holes and scattered sawdust from the beetle. Since the entry holes are only about the size of a #2 pencil lead, close inspection is necessary to detect these attacks in time to treat. Ambrosia beetles attack many types of trees and shrubs including crape myrtles, cherries, oaks, sweet gums, pecans, peaches and others.

The ambrosia beetle’s first flight occurs with mild weather typically in February but possibly as early as January. Cold weather will put them off for a while, but we usually see a big emergence of the granulate ambrosia beetle ranging from February in south Georgia to early March in north Georgia.

Young trees in nurseries and trees that have been in landscapes for less than three years old are vulnerable to attack even if they are not obviously stressed. This is especially true during the green-up period. Prompt action can save these trees if the number of attacks (“toothpicks”) is less than 4 – 5 per tree.

Growers of nursery trees and shrubs, as well as landscapers with new trees, can apply a spray to protect vulnerable trees. The spray should be repeated every 10 – 14 days until the plants are completely leafed out.

If applied in time, pyrethroid insecticides can repel the beetles even after plants are attacked. Pyrethroids like permethrin (Pounce, Astro), Talstar, Decathlon, or others will work. Once the trees have leafed out completely, they are less attractive to the beetles unless the trees are under stress. Prevent stress to shrubs and trees to lower chance of ambrosia beetle injury.

Spray affected trees, being careful to cover the trunk completely. Monitor the trees for signs of wilting of the new leaves, a sign that a pathogen has been introduced. Once the wilting starts, the tree will probably die. Do not assume the attack will be fatal, since trees may recover. Also watch treated trees to see if new toothpicks develop – a sign that the ambrosia beetles are still active.

Nursery trees that are attacked should be sprayed and separated from the rest of the block (if possible), and watched closely for signs of wilting. Nursery trees that are attacked but don’t wilt may not need to be destroyed. If they leaf out and seem healthy and no further toothpick formation is noted, then the small holes will heal quickly and leave no permanent damage.

If you see toothpicks on larger trees, the tree is probably severely stressed. If attacks are confined to one limb, pruning is an option. If the attacks are on the main stem, prepare to remove the tree if it dies.

Considering the history of this pest in Georgia, there is a good chance that any given nursery or landscape will suffer little or no damage and spraying will not be necessary. Watch susceptible trees or shrubs closely for beetle attacks.

Traps can be used to monitor the activity of this pest. For more information on constructing Ambrosia beetle traps see Activity Monitoring in this publication.

Winter Insect Management Calendar

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Bagworm

Information supplied by Kris Braman & Will Hudson, UGA Entomology Department

As you visit landscapes, scout for these insect pests this winter. Notify your client when you find damaging levels of insects or mites.

Click on the insect names to find information to help you identify & manage these pests. Notes after the insect’s name explain what you should do for each insect if control is necessary.

This publication offers help to manage landscape pests. –

For pesticide recommendations, see the Pest Control Handbook.

Shrubs 

  • Southern red mite (azalea, camellia, holly) – Scout and spray a miticide for these pests
  • Armored scales (boxwood, camellia, holly, gardenia, etc.) –  Treat with dormant oil

Trees

  • Bagworms – Prune them out. These bags contain hundreds of eggs that may hatch next May
  • Maple borers – Prune out small branches with these pests. Improve health of the tree with proper care
  • Bagworm
    Bagworm, John-H. Ghent, USDA Forest Service, Bugwood.org

    Lecanium scale – Treat with dormant oils

  • Spruce spider mite – Spray for these pests
  • Twig pruners and twig girdlers – Prune and destroy dead branches, and pick up and destroy fallen branches to prevent insect emergence next year.
Lecanium scale, Andrew J. Boone, South Carolina Forestry Commission
Lecanium scale, Andrew J. Boone, South Carolina Forestry Commission, Bugwood.org

Turf

Please share this information with others in the landscape & turf industry. For more information:

Call your local Extension Agent at (800) ASK-UGA1 or

Locate your local Extension Office at http://www.caes.uga.edu/extension/statewide.cfm

Pest Management Handbook (Follow all label directions when using any pesticide) – www.ent.uga.edu/pmh/

Using IPM in the Georgia Community Garden

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You may have heard about integrated pest management (IPM) and wondered if it is something only farmers use.  Actually IPM has a real place in any type of gardening, including your community garden plot.  According to the UGA Integrated Pest Management website this is the definition of IPM:

It is a science-based decision making process that employs biological, mechanical, cultural, and chemical control methods in such a way as to minimize economic, environmental, and public health risks associated with pests and pest management practices.

Notice it is science-based decision making.  This is important.

In practice, the gardener employs many different strategies to combat an insect pest or disease instead of just reaching for the chemical spray.  For a very basic example a gardener wants to grow tomatoes knowing that Fusarium wilt can be a problem.  (Fusarium wilt is a fungus that lives in the soil and infects plants through their root systems.)  This gardener will employ IPM by:

  • Fusarium wilt on tomatoes. Photo from bugwood by William M. Brown, Jr.
    Fusarium wilt on tomatoes. Photo from bugwood by William M. Brown, Jr.

    making sure his/her soil is healthy

  • growing healthy plants using recommended fertilization and watering practices
  • learning about the Fusarium wilt fungus and its biology
  • choosing tomato cultivars that show resistance to Fusarium wilt – these will have the letter “F” after the cultivar name
  • caring for garden equipment by proper disinfection and not using equipment from another gardener that has not been disinfected
  • being aware of the hot, dry weather that favors Fusarium wilt and looking for wilting especially during these conditions
  • destroying any infected plants
  • practicing crop rotation

With IPM, actions are taken to prevent diseases and pests from becoming a problem.  Rather than simply eliminating the pests that are found right now,  using IPM means the gardener will look at environmental factors that affect the pest and its ability to do damage.  Armed with this information, the gardener can create conditions that are unfavorable for the pest.  Know your enemy!

Your local UGA Extension agent can help you make a positive disease or insect identification so that you can make a plan to deter the problem.

Aphids on tomatoes from bug wood. Photo by Brian Kunkel
Aphids on tomatoes from bug wood. Photo by Brian Kunkel

Learning when and where an insect pest lays her eggs can help you find those eggs and remove them.  Determining what weather conditions favor a disease can help you adjust your planting date to avoid the peak of the disease.  Finding out how a disease is spread can also help you combat it.  Is it soil-borne or are fungal spores spread with wind?  Also, what beneficial insects prey on your insect pest and how can you attract those helpful insects?

Subscribing to this blog and other researched based information sources can help you know what diseases or pests are problematic in your area and what you can do about them.

If you haven’t visited the Upcoming Classes page of this blog, please do so.  There are many classes and workshops coming up.  Many are free and some are offered online.

Happy Gardening!

 

 

When is the best time of year to control fire ants?

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Fall is the best time to control fire ants!

Original story by Sarah Lewis, student writer with the UGA College of Agricultural and Environmental Sciences

“April and September are good times to apply baits, once at the start of the season and toward the end to help control before they come back in the spring,” said Will Hudson, a professor with the UGA College of Agricultural and Environmental Sciences.

Fire ants are most active in warm weather. Fire ant season can last 10 to 11 months out of the year in the most southern areas of Georgia. Controlling ant colonies before they produce a mound is important. However, Hudson says that once a treatment program is in effect, timing is not all that important.

Baits and sprays

The general rule of thumb is if the area is one acre or less, don’t use baits. Re-infestation is more likely from colonies outside of the yard when baits are used.

One important thing to remember is the difference between ‘no mounds’ and ‘no ants.’ “There is a difference between eliminating ants and controlling them,” he said. “Baits do not eliminate ants because there is no residual control. A new colony can still come in and be unaffected by the bait laid down prior to their arrival.”

To eliminate mounds completely, apply baits every six months, Hudson said. “There will be invasion in the meantime, and you will still have fire ants, just not enough to create a new mound,” he said.

Hudson recommends treating lawns smaller than an acre with a registered insecticide in a liquid solution. This should rid the lawn of fire ants for one to three months. If you choose a granular product, measure carefully to be sure you apply the correct amount of material and get good, even coverage, he said.

The least effective treatment option for most people is individual mound treatments, according to Hudson. Treating mounds in general is going to be an exercise of frustration, and killing an entire colony by treating just the mound is a challenge, he said.

Minimal impact

Baits are considered to have minimal environmental effects for those who chose not to use hazardous chemicals. Once the bait is out, there is hardly anytime for anything to come in contact with it before the ants get to it.

Nonchemical options include using steam or boiling water. “We recommend using boiling water to treat a mound near an area such as a well where you do not want any chemicals,” Hudson said. “Using hot water is very effective, but the problem is you are not always able to boil the water right next to the area you want treated.” Carrying the boiling water can inflict serious burns, so extreme caution should be used when treating with this method.

There are products on the market that are approved by the Environmental Protection Agency and labeled as organic. Hudson says organic designation is a “slippery” definition. There is an official USDA certification and many states have their own set of regulations when labeling a product as organic. This labeling can mean the product is either a natural product or derived from a natural product. “While there are a few products that qualify as organic, with most baits the actual amount of pesticide applied is minimal,” he said.

Realistic expectations

Hudson says to be careful when choosing a product because the labels can be confusing, even deceptive, and it is difficult to make the right choice. For assistance in selecting a product, contact your local UGA Cooperative Extension agent.

“The most important thing to remember is that you need to be realistic in your expectations,” Hudson said. “If you are treating mounds, you need to be prepared. You are going to chase the mounds around the yard.”

For more information on selecting a control measure:

Find pesticide recommendations in the UGA Pest Management Handbook

Fire Ant Control Materials

Managing Imported Fire Ants in Urban Areas

Fall is the best time to treat for fire ants

 

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