All posts by Hulett Environmental

The Truth About Citronella as Repellant

The Truth About Citronella as Repellant

Mosquitoes are here to stay and are, in fact, increasing.  Warmer weather due to climate change means mosquito habitat is expanding, and with it a host of dangerous diseases like dengue-fever and malaria.

A variety of sprays work to keep mosquitoes away, but some prefer the “all natural route.”  The most common repellent in this category is citronella, but there are a few facts you should know before running out and buying a supply.

First, a commonly known “citronella” plant is actually a species of geranium, called Pelargonium citrosum.  This is not the plant that produces the oil used in citronella candles, but it does carry a remote smell of citronella.  It is the better known plant, lemongrass (Cymbopogon), that actually produces citronella oil – but this plant puts off only a whiff of the odor and unless you weave a lemongrass outfit for yourself it will not repel mosquitoes.

Citronella in a spray is only marginally effective.  Although it is are registered officially as a repellent in the U.S., European countries do not allow citronella.  Its effectiveness really is debated, but if used it needs to be applied frequently – about each hour.  In addition, just because it’s “all natural” does not mean it is not toxic.  In fact, based on studies done on rabbits, the oil is more toxic than DEET.

The oil used in citronella candles is far too mild to repel mosquitoes.

 

A Bug’s View and a Robot’s Body

A Bug’s View and a Robot’s Body

This is one project that took vision.  The fields of mechanical engineering, neuroscience, computer science, and entomology meet in the development of a new robot that sees the world like an insect would.

And that is a good thing, because insects have unique visual advantages used to see and track prey.

The research combines best traits of humans and insects to produce a robot capable of tracking down an object.  Researchers from University of Adelaide have published their findings in Journal of The Royal Society Interface.

“Detecting and tracking small objects against complex backgrounds is a highly challenging task,” says the lead author of the paper, Mechanical Engineering PhD student Zahra Bagheri.

Robot engineers seek to create a mechanical kind of Frankenstein that has all the qualities necessary to negotiate a complex environment.  Great vision, coordination and flexibility are all desired traits in creating any near-living entitiy.

This team of scientists uses an algorithim that focuses more on the background than the vision itself, one that’s been tested in virtual reality technology.  This active vision is biologically inspired through the study of how insects find and track their prey and move through their environment.

“This type of performance can allow for real-time applications using quite simple processors,” says Dr Wiederman, who is leading the project, and who developed the original motion sensing mechanism after recording the responses of neurons in the dragonfly brain.

Humane Ways to Take Care of Pesky Bugs

Humane Ways to Take Care of Pesky Bugs

Insects are a fact of life, but it’s only natural to want a bug-free home.  If you have an infestation, or simply want to control disease-carrying varieties like mosquitoes, it is possible to remove them without harm to your or the bug.

The most common and troublesome types of bugs include ants, wasps, and roaches.   Each of these types can be prevented or removed rather than killed.

Ants can be dealt with through observation.  Follow any line of ants back to its source, leave a piece of lemon peel or some lemon juice there.  Or, use mint, cinnamon, coffee grounds, chili or cloves.  Peppermint spray can be used in cracks and nooks of your house.

Wasps are less loved than bees, but they are also pollinators.  Spraying with water can work, but can also provoke them.  For prevention, take advantage of their territorial nature and put paper bags where nest might pop up.  Such bags look like wasp nests, and they won’t settle if they think other wasps are nearby. Smoke also works, and like tear gas does them no substantial harm but will cause them to move away.

Cockroaches can be prevented by keeping your living space clean.  Seal all containers of food, don’t leave dirty dishes out, and take the trash out regularly.  Roaches also avoid certain foods, so these can work as a deterrant:  bay leaves, garlic, catnip and, surprisingly, cucumbers.

Mosquitoes May Carry Another Fever

Mosquitoes May Carry Another Fever

Rickettsia felis is a bacteria that causes fever, muscle aches, rash and headache.  It lives in African countries where malaria is also common.  Until recently, it was believed to be transmitted by fleas and ticks, but new research shows there may be more to the story.

Diseases with fever symptoms are common in Africa, and therefore distinguishing between their types, symptoms and origins is critical.  R. felis was originally identified and studied in places where “fevers of unknown origin” are common.

To learn how R. felis may be transmitted, scientists found mosquitoes known to carry malaria and fed them with blood carrying either R. felis bacteria or another types.  They found the disease-causing R. felis bacteria in the mosquitoes after feeding them, and also observed the bacteria being transferred to neutral mediums, like cotton, via mosquito saliva.

Using mice, researchers were able to confirm the R. felis bacteria could be easily transferred to mammals and sicken them.

Further research in this region is needed to understand exactly how R. felis is transmitted, so that public health precautions can be used to reduce exposure to the bugs as well as the disease they carry.

How to Choose A Pest Control Professional

How to Choose Pest Control Pro

We who own homes spend much of our free time maintaining our space to prolong the value of the house and keep ourselves (and family members) comfortable.  Even if you are a diehard do-it-yourselfer, pest management is a task most people contract with a professional.

Typically, homeowners call the exterminator only after insects arrive. Whether doing preventive treatments or responding to an emergency, you should know where to go.

When it comes to choosing the right exterminator, following these general guidelines:

  • Ask for recommendations from friends and family
  • When evaluating a company, ask for credentials
  • Compare companies and search for value rather than price. If the job is expensive, get bids.
  • Make deliberate decisions, don’t rush

Read the guarantee and know what it covers.  It is your responsibility to educate yourself about what you are paying for.  You should understand what the guarantee does and does not include, how long it lasts, and what kind of continuing prevention, treatments, or inspection may be necessary.  What is your role in keeping the guarantee enforced?  Additionally, make the company is insured in case of an accident.

Do your research: check with your regulatory agency – typically the state Department of Agriculture – for details about any company doing business in your area.  It is also helpful to become informed about the nature of whatever pest you are dealing with before and during your negotiations with a pest control company.  Your own knowledge helps create a more productive dialogue with the technician who comes to your home.

The Seasonal Attack of White Grub

The Seasonal Attack of White Grub

They will unapologetically eat your lawn, and you may not even know they are there.  A few telltale signs can be all you need to remove these root-crunching grubs from your life, however.

They go after the roots of grass and therefore can kill large amounts of your beautiful green yard.  To avoid this, inspect your lawn periodically for dead patches that are effortlessly pulled from the earth.  Since the grubs have consumed the roots, the turf is easily removed.  By digging up the patch, you can count the small white larvae; if you have more than 3 per square foot, you should begin treatment by calling a pest control professional or researching home treatments.

The dead patches are usually not noticeable until midsummer, but the grubs first begin feeding in early spring.  If you can wipe them out the summer after they begin chomping away, the yard can be easily restored.  The second stage, after their first winter hibernation, is the most damaging.  By then, those grubs have matured and laid more eggs, underground.

By the next spring, all those satiated little grubs will have become mature, reproducing insects.  By then it will be much more difficult to eradicate them.

Spider Silk Crawling Toward a Market Near You?

Spider Silk Crawling Toward a Market Near You?

Could silk from spiders be the next breakthrough in fabrics?  Scientists and entrepreneurs have been searching for decades to find a way to get this amazing substance to market.  But starting a spider ranch is not as straightforward as one might suspect – and all sorts of attempts have been made.

Spiders are not cooperative in the ways that silk worms are.  They are territorial, for starters.  Another barrier to setting up a successful colony of silk-weaving arachnids is that they tend to be cannibalistic.  Not ideal for fashioning a bustling spider neighborhood.

A startup with $40 million in funding called Bolt Threads may have broken through the silk barrier, however.  The trick to making the best spider silk is to do it without actual spiders.  Bolt has developed genetically engineered organisms, through a yeast fermentation process, that can produce large quantities of silk.  That part of the process has been known for years, but the new technology uses a proprietary liquid bath to coat the silk proteins and transform them into the usable end product of solid fibers.

Bolt CEO Brian Widmaier recently explained that the process is superior to using raw spider silk because the proteins can be manipulated to emphasize various qualities of the fiber. Bolt can make spider silk that’s stronger, stretchier, or waterproof, for example, depending on preference. “What we’ve learned is we could prod nature a little bit in the lab and engineer these new properties in,” says Widmaier.

 

Allergic Attacks from Bugs: The Basics

Allergic Attacks from Bugs: The Basics

A quarter of allergic reactions come from bug bites. Some of us just don’t react well to what are benign encounters for the majority of people. Other allergies are the result of food (about half) or drug (the last quarter) reactions, but allergic responses to bugs can be quite deadly.

The lethality of an insect bite is linked to the reaction known as anaphylactic shock. Anaphylaxis is a sudden drop in blood pressure, typically accompanied by itching, feeling hot and flushed, possible palpitations and difficulty breathing, and sometimes a racing heart. With these symptoms, a person may become unconscious.

Any anaphylactic reaction should be considered a medical emergency. People with bug allergies of this type should carry an Anapen or Epipen and a written action plan, so that medical workers can treat the reaction swiftly and properly. For more details on first aid treatment for allergies, the ASCIA provides a website.

Other potentially dangerous allergies come from the stings of honeybees, ants, and wasps. These are some of the more common insects that cause serious problems for those susceptible to anaphylaxis.

Tick allergies are much more rare, but do occur. Ticks should be removed gingerly but if you have an allergy the tick should not be removed by any means. Instead, seek medical attention at your nearest emergency room.

 

The Evolutionary Advantages of Not Having Sex

The Evolutionary Advantages of Not Having Sex

Entomologists are struggling to answer basic questions about how an “anti-sex” pheromone has developed in honeybees, ants, and wasps. Scientists who study animal behavior say that explaining the use of this pheromone, which keeps “worker” insects sterile, involves a great deal of speculation at our current level of research.

Buff-tailed bumblebees are considered “eusocial” and have queens that engage in all the reproduction. Female worker bees do not develop ovaries, but pass on their genes via the good of the larger group. Their worker status helps the whole hive, and since all bees within one hive are closely related, genetic materials are passed on more indirectly.

Yet scientists are still mystified as to why eusocial insects involved the trait of sterility. It is difficult to understand how a trait that reinforces lack of reproduction could benefit any species.

The mechanism of enforced sterility is better understood, however, with recent research. It turns out that the queen produces a chemical (pheromone) that signals to workers to not engage in reproduction. This compound is a long-chained hydrocarbon that is abundant within the queen bee. Scientists speculate that development of the pheromone happened millions of years ago, when insects lived more solitary lives, perhaps as a way to attract males or deter other females.

Rapidly Evolving Roaches Just Say No To Sugar

Rapidly Evolving Roaches Just Say No To Sugar

Within a few years, roaches have evolved to avoid sugar.  Remarkably, their adaptation is a result of sugar-laced traps.  Unlike humans, they don’t have to use willpower.  Instead, roaches have a built-in aversion based on taste:  sugary flavor comes across as bitter.

Roaches in a recent studied were sampled from colonies in the U.S, Puerto Rico, South Korea and Russia.  Among the 19 populations examined, seven included roaches with the sugar-aversive behavior.

Researcher Coby Schal of North Carolina State University noted that the evolution came about “incredibly fast” but also pointed out that some bacteria evolve even more quickly.

In a simple experimental design, researchers filmed roaches to understand their behavior.  The study videotaped groups of roaches as they chose between two food sources.  The bugs were given a choice of a glucose or fructose based jelly, and later, peanut butter or jelly, and observed as they made their choice.

The phenomenon of glucose aversion has been for known some time in the extermination industry, and profession pest-control companies have switched to new types of bait, either high carbohydrate or high protein.

This latest research demonstrates just how well cockroaches learn, and how exceptionally adaptable they are to a variety of challenges.