The invasive Caribbean crazy ant resembles a few other ant species in its large colony sizes and "crazy" running behavior. Identification is best handled by the Texas A&M Entomology lab.

The tiny crazy ant, known either as the Rasberry crazy ant or the Carribbean crazy ant, is now in the Austin area.  See the story from the Austin American Statesmen, for more information.  I won’t say much about this except to note that this is thought to be a mostly tropical ant, and the general consensus is that it won’t do as well where winters are cold and humidity is low.  Whether it will turn out to be a serious problem in relatively dry Austin, or whether it will establish as far north as Dallas is yet to be seen.

The Austin American Statesman article gives instructions for sending these to an entomologist in College Station for identification.  Also, you can check out the website at Texas A&M for more information on these little gals.

The large size, gray color and rows of black docks distinguish giant bark aphid.

The giant bark aphid, Longistigma caryae, is the largest aphid in North America. Despite its large size, I rarely receive reports of this insect because in most years its numbers are so low. This year, however, Extension specialists have already had multiple reports of the aphid. One of the last times I reported on an outbreak of giant bark aphids was 2002, coincidentally (or not), also during a spring that followed a mild winter.

Giant bark aphids are about 6 mm-long (1/4 inch), brownish gray with black spots. Their long legs, which makes them appear even larger, give them a spider-like appearance. Males and some females are winged but egg laying females are wingless. When alive they are often partially covered with a bluish white, waxy secretion. The gray body and rows of black spots along its back helps giant bark aphids blend in well on bark.

Unusually, for an aphid, damage to trees from feeding can be severe. It is not unusual for infestations to cause branch and limb die-back.  A tree farm in east Texas this spring reported loss of a number of redbud trees, and Shumard red oaks.  In addition, wax myrtle and cedar elm were severely damaged. Pecan, hickory, willow and live oak trees have also been reported as hosts for these aphids.

Where heavy infestations occur, the aphids can literally blanket twigs and branches. When this occurs it is not uncommon to find sticky pools of plant sap under trees. If you find these sap pools or clusters of aphids on your tree, I suggest taking prompt action to remove or kill the infestation.

Another type of giant bark aphid, Tuberolachnus salignus is specific to willow, and is probably shown in this picture taken on an "aussie" willow in Lewisville, TX by Lee McClurg. T. salignus has a bump, or large "conical tubercle" on its back.

On smaller trees, aphids may be controlled with a stiff stream of water from a hose. The safest course for larger trees, may be to spot-treat infested branches and trunks with a spray of imidacloprid, malathion, or acephate (Orthene). Bifenthrin has also been reported to be an effective treatment, suggesting that pyrethroid sprays labeled for trees may be a good choice.  Insecticidal soap or horticultural oil sprays are the low-impact choices, and may also be effective, although these sprays will require direct wetting of the aphid to get good control.

Consider sharing your experience with these aphids using the comment box below.  If you have an infestation to report, include the name of the tree or shrub affected, along with your city and county.  Thanks.

Migratory red admiral butterflies in Plano, TX last week. Such migrations are usually short-lived as butterflies move through an area. Photo courtesy Rich and Nikki Lefebvre.

In case you haven’t been paying attention, this spring has been great for butterfly and moth watchers in Texas.  A few weeks ago I noted the abundance of armyworm moths, and last week I had several questions about all the butterflies on the wing.  This week county extension agents in west Texas reported large numbers of the migratory army cutworm in and around towns.  The picture accompanying this article was sent by Rich and Nikki Lefebvre, Master Naturalists in Plano.  It shows an impressive number of red admiral butterflies on the side of their suburban house. Red admiral butterflies, monarch butterflies and army cutworms are all examples of Lepidoptera (lep ih DOP tura–the Order name for moths and butterflies) that exhibit migratory behavior.  Hence the high numbers of these species are just “passing through” on their way to somewhere else.  If you are lucky enough to witness one of these migrations, get out your camera now because they typically don’t last long.

I’ve been asked many times for an explanation for these “outbreaks” of moths and butterflies.  The only answer I can give is that favorable weather can increase survival of many lepidopterous species.  This year a mild winter combined with a wetter than average spring has likely favored survival of overwintering butterfly and moths.  The rain also favors food plants, which helps sustain a population spurt.

Sometimes the answer is likely to be more complex.  For example, I’ve received several calls about caterpillars defoliating oak trees in counties to the north and west of Dallas, along the Red River.  This appears to be Cissusa spadix, the caterpillar of the black-dotted brown moth, which is known for its occasional outbreaks.  This insect has likely benefited not only from the mild winter, but also a slow population buildup for a year or more.  Many factors go into caterpillar and butterfly “invasions”, including weather, food availability, past population trends and the presence of natural enemies.

For a listing of butterfly species currently being seen in north Texas, check out the Dallas County Lepidopterist’s Society webpage, and click the link on the left lower side labeled “What’s on the Wing”.

Phaedon desotonis, a small, bronzy-colored beetle, defoliates a Coreopsis plant in Blanco Co. (Photo by Sheryl Smith-Rodgers).

Some of you may be lovers of the spritely flower called Coreopsis.  If so, bad news. A tiny leaf-feeding beetle with the tongue-twsting name of Phaedon desotonis has been showing up in occasional outbreaks around the state.  I recorded one in Caddo Mills, TX (Hunt Co.) this month two years ago, and blogger Sheryl Smith Rogers reported (and photographed) an infestation last week in her backyard in Blanco Co. (west of Austin).

Mike Quinn provides two more links to information on this native pest for those of you who would like to learn more:

• Pest Alert from Florida Department of Agriculture and Consumer Services
• Bugguide

Ed Riley, from the Department of Entomology at Texas A&M theorizes that this may be a case of an insect herbivore suddenly expanding its host preferences to new plants which were not previously on their list of favorite foods.  If true, it may take a little while for this pest’s natural enemies to adapt to find it on its new host.  Many natural enemies learn to find their favored prey by first searching their prey’s favored host plants.  This might be a way that some herbivores stay one step ahead of their enemies.

Let’s hope for the sake of Coreopsis that the predators wise up quickly.  If you are seeing this insect on your Coreopsis, please consider commenting on this article by describing where you have seen this insect occurring (include the city, state, county and date of observation).  Thanks.

Even the largest and most beautiful of insects, such as this newly emerged luna moth, are easily overlooked by someone not accustomed to "seeing small".

Few would argue that March and April are a great time to get outside to enjoy the weather in Texas, tornadoes notwithstanding.  But how many think of spring as great insect-watching weather? Well it is. A multitude of insects break their winter dormancy at the same time as their host plants.  This leads to great abundance of interesting subjects for those who have eyes to see.

The biggest obstacle to insect watching, I find, is the common inability to “see small”. While there are some impressive large insects–most notably butterflies and moths–most insects are tiny, the size of a pencil eraser or smaller.

The idea of having lots of insects around may be repulsive to some people.  This is unfortunate, and likely due to a few bad characters–like mosquitos and ticks.  But by large most of our six-legged neighbors are quite happy minding their own business and staying out of our hair.

This silent majority of insects, with careful observation, can be found exploring plants and staying as far from people as possible.  For example, the luna moth caterpillar, the immature stage of one of the most beautiful moths in America feeds on pecan trees.  There it spends its days well camouflaged by its host’s leaves.  And despite their large size (by insect standards) luna moth caterpillars are rarely seen by people, and rarely cause damage that we would notice.

My wife and I almost missed the newly emerged luna moth in the accompanying picture last weekend on a hike in the Ouachita Mountains of southeast Oklahoma.  Resting on a twig just a few inches from the trail, it was pure luck that my eyes were able to focus on this springtime beauty. With wings still in the process of filling and stiffening with blood, the moth was a perfect poser.  As I focused with my camera I marveled at how difficult it is for our human eyes to adjust to seeing small things after living in the giant world of buildings and streets and cars.

Interestingly, luna moth damage, like that caused by many other native caterpillars, is rarely harmful to trees. This is because other native insects, like the ichneumon wasp, Enicospilus americanus, are specialists in stalking and parasitizing luna moth caterpillars.  These delicate, golden insects very carefully prowl only those trees where the luna moth caterpillar feeds.  Rarely are the hunter or the hunted seen, but the deadly hide and seek game between the two species keeps both insect populations healthy but relatively rare.

Each year thousands of people spend a great deal of money to travel to exotic places on safari to see wonderful wildlife in action, yet a short trip to the backyard can yield similar wildlife-watching pleasures.  If only we can “see small”.

White grubs present now in the lawn and garden soil pose little threat to the landscape.

As winter ends the good earth beckons. If you need proof, just listen this weekend.  Like rattling sabers, you’ll hear gardeners everywhere dragging their spades, mattocks and hoes from storage. It’s an inevitable ritual of spring.

Just as inevitably, many gardeners will gasp as their thoughts of seed packets are interrupted by the sight of glistening white grubs in the newly turned soil.

White grubs are the immature life stage of the June beetle and its relatives. And as most Texas gardeners know, white grubs are not good.  After all, grubs are one of those pests pictured on bags of insecticide  at the local Home Depot, so they must be bad–right? Well yes, sort of.

The real question is whether we need to treat our gardens and lawns now to kill lawn-eating grubs? The answer is no. White grubs present in lawns (and many of those in garden beds) are almost always one of two species of scarab beetle known as the June beetle and the masked chafer.  Both species can be damaging to turf in late summer, though feeding during the winter and spring is insignificant. The grubs we turn over in the spring garden are essentially in hibernation.  They remain in a non-feeding state until May, when they undergo pupation before emerging from the ground as an adult in June and July.

As alarming as these juicy springtime grubs appear, they do little harm to plants in the spring.  The harm comes between July and October after this spring’s June beetles have laid their eggs, and when the next generation of grubs is feeding underground. These late-summer white grubs are the pests in that they feed on the roots of our common turf grasses.

If you were to apply an early-season insecticide now, its potency would be diminished by the time it’s really needed in July and August.  And even if your treatment did kill grubs present now, they would be replaced in June when adult June beetles fly in from surrounding lawns and landscapes.

An April-emerging scarab beetle common right now in parts of Dallas is of no concern to lawns or gardens

Although most damage to Texas lawns is done by just a very few species of white grubs, there are over 100 species of similar-looking beetles in the state. Most of these scarab beetles are harmless, feeding on compost or the roots of plants of little concern to us humans. Which brings me to a second observation that many of us are making this week.  The June beetle-like beetles coming to windows and lights during April and May are not species that attack landscape plants. Most of these beetles lack a common name, although you might call some of them April and May beetles based on the timing of their mating flights.

Again, nothing to worry about, apart from the incessant bumping and banging against window screens.  For more information about white grubs and their control, see our publication E-211, White grubs in Texas turfgrass.

Storm drain catch basins can be important breeding sites for summer mosquitoes.

A recent article in the Journal of Medical Entomology on mosquitoes and sewers caught my eye–yep, I know, most people would skip that one.  But the study does shed light on an important public health topic, namely factors that can influence the spread of West Nile virus (WNV) and other mosquito-borne diseases.

Allison Garner (University of Illinois-Urbana) and colleagues conducted their study in a Chicago area residential community during the summer of 2010.  They looked at mosquito breeding in sewer catch basins over the course of a summer.  Sewer catch basins are found under grates on streets and parking lots.  They are designed to catch some of the mud and trash that falls into sewers during rain storms, helping keep it out of larger catch basins or streams.

Now sewer catch basins are not generally nice places to be, but mosquitoes seem to like them.  Garner and coworkers sampled mosquito larvae from 19 catch basins over the course of a mosquito season and found a strong correlation between dry, hot weather and Culex mosquito populations. Culex mosquitoes are the most common vectors of WNV in Texas.  They are one of our container breeding mosquitoes, but are most commonly found in dirty, yucky water where fish and other mosquitoes don’t survive well.

Now the interesting thing about the Illinois study is that mosquito numbers were very low after periods of rainfall, but highest during the hottest and driest part of the summer.  This is the opposite of what most people think about mosquitoes, especially since the most obvious mosquito do occur right after a spell of rainy weather.  So which is worse, wet weather or dry weather, for mosquitoes?

It turns out that wet weather mosquitoes, also known as floodwater mosquitoes, are larger and produce a more painful bite than the house mosquito in the genus Culex.  Culex mosquitoes, on the other hand, are the ones that are mainly responsible for disease transmission in Texas. This correlates well with the patterns of WNV occurrence in the Dallas area.  We see WNV occurring mostly in bird and human populations during mid- to late-summer, when storm drains produce the most mosquitoes.

Catch basins typically hold water for days to weeks after a rain. When leaves or grass clippings accumulate in the basins, ideal breeding sites for mosquitoes are created.

So why more mosquitoes during the dry season?  The authors of the Illinois survey conclude that rains tend to scour the storm sewer catch basins and wash away any Culex larvae breeding there.  When the temperatures warm, mosquitoes can breed more quickly.  And when the inevitable dry spell arrives, the mosquitoes still have these stagnant catch basins all to themselves, perfect for breeding.  Of course if the drought lasts too long, even storm sewer catch basins dry up and mosquito breeding slows.  This may be at least part of the explanation of why during the extreme drought of 2011, we had one of the lowest number of WNV cases and deaths in Texas since 2002, when numbers were first recorded.

The message from all this is that we should not let down our mosquito defenses when the rains stop this summer.  That’s when the Culex mosquitoes really become the problem. The most insidious part of the story is that the Culex house mosquitoes are very stealthy biters.  They tend to be out at night, and the bites are not as noticeable or painful as the wet season mosquitoes. So if you are active outdoors in the evenings or early morning hours, don’t neglect mosquito repellent–even in the dry summer months.  Once the temperatures get into the 60s and above, mosquitoes will be there.

For more information about different kinds of mosquitoes and mosquito control in backyards, check out the Mosquito Safari website.

Armyworm moths are about an inch long with a 2-inch wingspan. The front wing in tan and mostly plain, often with a white spot in the middle. This moth was hiding in the grass in my back yard.

Whenever there’s a slightly unusual weather pattern I can predict the calls.

“So what’s the mild weather going to do to the pests?”  ”Did the cold snap in January kill all the bugs?” “Will all this rain mean more insects?”

The truth is that most Texas insects are pretty well adapted to our coldest weather, and also darned difficult to predict.  Sometimes entomologists will venture a guess for a reporter, and might even be right more often than not. I’ve learned, however, to be a little more circumspect in my predictions.

Indeed, in the past few weeks I’ve given a few television and newspaper interviews about the mild winter.  So far, I’ve been willing to go on record predicting an early start to the insect season, but I am still hedging my bets on longer term predictions. So much can happen and, frankly, there are not that many insects that entomologists have studied long and carefully enough to make accurate seasonal predictions.  On average I think the Weather Service is better than us insect experts at predicting the future; but I still don’t put too much stock in long-term weather forecasts.

Well, at last there may be an insect to satisfy the media’s desire for a good “plague” to report.  It’s called the true armyworm, and there have lots of them fluttering about the past couple of weeks in north Texas. And it’s not just farmers who are seeing them this year. True armyworm moths seem to be uncommonly abundant in towns and cities, at least in my part of north Dallas.

Armyworm moths can now be seen flying about city streets, fluttering around porch lights and hiding in lawns and bushes.  But the moths are not the problem–it’s their children.  Armyworm moths lay eggs that turn into armyworm caterpillars.  And armyworm caterpillars feed on grasses, including a lot of valuable crops like wheat.

According to my colleague Dr. Allen Knutson, it’s not normal to see armyworms this early in the year.  Armyworms are normally killed by freezing weather, and in usual years only make into north Texas farmers’ fields in mid-April or so, after flying from points south of San Antonio or Corpus Christi.

“The moths I’m seeing right now in the Dallas area are in pristine condition,” Knutson said.  ”This suggests that these moths most likely came from locally raised caterpillars.”  Moths that travel long distances usually have worn wings, and show the effects of travel.

Armyworms get their name from the gregarious behavior of the nearly full-grown caterpillars.  In years of abundance they are known to form large bands or “armies” of caterpillars munching their ways through prairies, farm fields, and even lawns.

County extension entomologists in north Texas have not yet reported any major armyworm outbreaks this year, but they are on the lookout. Especially because this year looks like one of the best wheat crops in decades in some areas. And even the remote chance of armyworm hoardes is enough to put farmers on edge.

Homeowners who see the large, tan moths in their yards should not be too concerned, however.  While armyworms can damage grass in lawns, they are more likely to build up large numbers in pastures or farm fields and then move into adjacent turfgrass.  Homes on the edges of undeveloped land or wheat fields would be most at risk, should the caterpillars flourish over the next few weeks.  Right now, however, these moths are more of a curiosity and a reminder of the forces of nature that are so difficult for us humans to predict and control.

I could predict a big year for armyworm outbreaks, but I won’t.  Mother Nature is too unpredictable.

For more information about armyworms, click here.

Ball's Pyramid, an isolated island in the Tasman Sea is home to the newly rediscovered Lord Howe's stick insect.

Are you a survivor?  Then maybe you can relate to the story of the Lord Howe stick insect, Dryococelus australis–at was 12 centimeters long, the heaviest stick insect in the world. It had been as presumed extinct until 2001 when two VERY COMMITTED Australian biologists followed a hunch and climbed up 500 feet in the dark with flashlights to have a look.

The story, published in an NPR blog is inspiring and offers a glimmer of hope for anyone who marvels in the diversity of life.  In an age when insect (and other animal and plant) species are disappearing at an unprecedented rate, this story is worth hearing.  Like numerous other island species (including many of the fauna on the Hawaiian islands) this species’ demise was driven by the introduction of commensal rats from ships.

One of the most inspiring speakers on this subject is E.O. Wilson, possibly the most famous entomologist of our time.  I hope you will check out the story of the Lord Howe stick insect, and if you have time, listen to Dr. Wilson address a 2007 TED conference on “the little things that run the world”.

The best place to apply granular or liquid insecticides is on a healthy lawn, mulch or foliage. Sweep any excess product back into the lawn or the original container for later use.

Ten years ago the most common lawn and garden insecticides for consumers contained the active ingredients diazinon and chlorpyrifos (Dursban).  These insecticides were popular because of their relatively quick kill, effectiveness against a wide range of pests, and ability to keep killing for several days to weeks or months.  Today those older products have been completely replaced with a group of insecticides known as pyrethroids.

Pyrethroids were judged to be safer both to people and the environment, however recent research has turned up some problems with pyrethroid use that gardeners should be aware of. New studies have shown that pyrethroid insecticides, which are not very water soluble–but do stick very tightly to soil, are increasingly being found in the sediments of urban creeks and streams.  Though not directly toxic to fish, these residues have been shown to be toxic to some invertebrate animals that live in stream bottoms.  This is an ecological concern because these benthic invertebrates form the base of the food chain in streams.  Kill the little critters at the bottom of the food chain and life all the way up to fish and wading birds are affected.

No one really knows for sure who is applying these insecticides that are ending up in streams, but we do know that any time pyrethroids are applied to impervious surfaces (sidewalks, driveways, the siding of homes and even bare soil, the chance of rainwater washing these pesticides attached to soil or dust is much higher.  For this reason, the Environmental Protection Agency is requiring new changes in the labels of professional and consumer packages of pyrethroids.

Much of the new wording on Pyrethroid Labels will be found in the sections on “Environmental Hazards Statements” and general “Directions for Use”, and they replace current wording with stronger wording to users of the products to avoid any application that would allow that product to move off of the intended site of use. One of the most common forms of misapplication by home users is likely applying pyrethroid granular products to sidewalks and driveways, or bare soil, where they can be washed into storm drains.

Using a pesticide is not necessarily bad for the environment, but it does require a few additional precautions:

• Sweep up excess granular insecticides from sidewalks, curbs and driveways.  Dispose of the granules on soil with vegetation or mulch; or if labeled for such use, apply to a pesky fire ant mound.
• Don’t apply insecticides to bare soil, especially before expected rain, as this increases the chance of contaminated soil eroding into streams where it is not wanted.
• Water-in insecticide applications made to soil immediately.  This is the most effective, and environmentally sound, way to apply granular or spray products for fire ants, white grubs and other soil pests.
• Avoid mixing or disposing of insecticide near a storm drain or curb gutter, and never pour excess insecticide into a sink or storm drain.  This is one of the surest ways for a pesticide to get into natural waterways. Pesticides are not easily removed from waste water, and storm drains empty directly into our rivers and lakes.
• Maintain an untreated buffer of 10 feet or more around streams and ponds when using liquid or granular insecticides.
• Always follow label directions carefully. The label is not merely a set of guidelines for use, it’s a legally binding document. Using more than the label directs, or using a pesticide in any manner not specified on the label, is a violation of federal law.