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MILKWEED PLANTS ARE OFTEN CONTAMINATED

       When it became abundantly clear, the monarch population was in decline private citizens, government agencies, and conservation groups launched an international effort to save this spectacularly beautiful butterfly.  One of the problems facing the monarch is a lack of the milkweed.  The milkweed is the monarch’s only known host.  For quite some time, thousands of us have been trying to remedy this problem by planting native milkweeds in our yards.  In response to the high demand for milkweeds, commercial nurseries expanded the propagation and marketing of these important caterpillar plants.  However, a recent study conducted by the Xerces Society and the University of Nevada found many of these plants are contaminated with chemicals that are potentially harmful to monarchs.

       The researchers tested the foliage of 235 milkweed plants sold at 33 nurseries scattered across the United States.  The researchers were trying to determine if any of these plants harbored chemicals that might be harmful to monarch caterpillars.

The study revealed the plants were contaminated with 61 different pesticides.  As many as 28 different pesticides were found in or on individual plants.  Another startling discovery was an average of 12.2 pesticides was found per plant.

 

       Ironically, plants advertised as “wildlife friendly” were not contaminated with fewer pesticides. Instead, many actually harbored more of the deadly chemicals than those not so labelled.  In fact, with respect to one pesticide, milkweed plants that were supposedly sold as being wildlife friendly had a greater chance of being contaminated with a dose of it that exceeded the known sub-lethal concentration.

       Matt Forister, a professor at the University of Nevada, Reno expressed his feelings regarding these alarming findings this manner, “In many ways, they are as contaminated or worse than plants growing on the edges of agricultural fields.  That was quite a surprise to me.”

       To date, the potential impacts of only 9 of the 61 chemicals on the monarch are known.  However, the scientists pointed out that 38 percent of the samples contained high enough concentrations of the chemicals that could affect the monarch’s ability to eat and migrate.

       Where does that leave those of us that purchase these plants?  The researchers recommend that we encourage the nurseries where we buy milkweed plants to sell only pesticide free plants.

       In addition, Aimee Code, Pesticide Program Director at the Xerces Society went on to say, “It’s important to keep gardening for pollinators for the long term.  Just take steps to reduce pesticide exposure: cover new plants the first year, water heavily, discard the soil before planting, as it may be contaminated, and avoid pesticide use.”

BACKYARD SECRET—THE COMMON BUCKEYE’S WINGS VARY IN COLOR FROM SUMMER TO FALL

       The common buckeye (Junonia coenia) is one of the most commonly seen butterflies in Georgia backyards.  It is seen so often that even somebody that has only a passing interest in butterflies is likely to familiar with it.  However, butterfly enthusiasts often are often guilty of not paying as much attention to the colors and patterns displayed on the wings of commonly seen butterflies as those species they spot less often.

       A good example of this is the common buckeye.  Have to ever noticed that the color of the ventral side of the wings we see displayed by common buckeyes flying about in the summer is noticeably different from those of buckeyes visiting our flowers in autumn?

       During the summer months, the undersides of the buckeye’s wings are tan or yellowish brown.  In contrast, the ventral sides of the wings of buckeyes flying about in the fall are rose-colored.

       Who would have guessed this is the case?

LOOK FOR LEOPARDS IN YOUR BACKYARD

        From spring into fall, leopards stalk our backyards.  I am not talking about the feline variety.  I am referring to the giant leopard moth (Hypercompe scribonia).

        However, like the predator, that roams the wilds of Asia and Africa, the giant leopard moth also has spots.  The spots on its wings vary from black to blue.  Some spots might even have white centers.  Once you see one, you will have no problem understanding why we call it the leopard moth.  Nevertheless, I think you will agree with me that it would have been more appropriate to name it the Dalmatian moth.

       The female leopard moth is smaller than the male. Males have a wingspan of 3.6 inches whereas the female’s wingspan is only 2.25 inches.

       The leopard moth has a variety of host plants including male, cherry, willow, sunflower, cabbage.

       If you want to see one of these handsome moths, the best strategy you can employ is to have the moth come to you.  Fortunately, leopard moths are attracted to lights.  Armed with that tidbit of information, just pull up a lawn chair near an outside light and wait.  (Lights with shorter wavelengths work best.)  If there is a giant leopard moth nearby there is a good chance it will appear.

       When a leopard moth finally shows up chances are will be a male.  For some reason, females do not visit lights as often as the males. 

       As you might expect, some folks will attract more leopard moths than others will.  I have never been able to attract more than one leopard moth at a time to my lights, nevertheless, some homeowners report seeing upwards of a dozen or more.

          

BACKYARD SECRET—ZEBRA SWALLOWTAIL CATERPILLARS ARE CANNIBALS

     One of the most striking butterflies that flutters about our yards is the black and white striped zebra swallowtail.  One of the reasons that it is far less common than the eastern tiger swallowtail is probably linked to the fact that it has only one larval host plant—the pawpaw.  On the other hand, the tiger swallowtail uses a variety of plants as hosts for its caterpillars.

     Faced with often scarce larval food plants, one of the ways that zebra swallowtail maximizes the numbers of caterpillars that reach adulthood is its caterpillars sometimes act as cannibals.  Let me explain.

     Female zebra swallowtails typically lay a single egg on the underside of a pawpaw leaf. However, at times they will lay two or more eggs on the same leaf.  When this happens and the eggs hatch one of the young caterpillars will often devour its rival. This cannibalistic behavior ensures it will not have to share precious food with a rival.

GOOD NEWS FOR MONARCHS

       For the past several years, it seems that the only news we heard regarding monarchs was discouraging.  Consequently, I was elated when Mexican butterfly experts recently reported that 35 percent more monarchs arrived in the pine and fir forests in November 2021 west of Mexico City which serve as their winter home than in 2020.

       Interestingly, these estimates are not determined by counting individual butterflies. Instead, they are based on the total acreage occupied by monarchs roosting in massive groups on the limbs of trees in this precious habitat.

       According to the Mexican government’s Commission for National Protected Areas, this past winter monarchs roosted on seven acres of forested habitat located high in this critical high mountaintop habitat.  Although this doesn’t sound like much during the winter of 2020-2021 monarchs roosted on only 5.2 acres.

                                MONARCH BUTTERFLY

      Gloria Tavera, the regional director of Mexico’s Commission for National Protected Areas, reports that in 2021 monarchs began departing for their summer breeding grounds in February.  For reasons that are not understood, these colorful orange and black butterflies left much later this year (they typically leave in March).  According to Tavera, “We still had butterflies in April.”  She went on to say, “It remains to be seen in next year’s figures whether that strategy worked for them.”

HOMEGROWN BUTTERFLY FEEDER

       Recently, a hard freeze brought an abrupt end to the growing season of many of our nectar plants.  The next morning when my wife and I walked outside and looked around the yard, it was not a pretty sight.  Mexican sunflower, cosmos and other plants were drooping and their flowers withered.  It was obvious that the butterflies that were still flying about our yard were in for some hard times. 

       Later in the morning when we noticed a cloudless sulphur was trying to nectar at a dead Mexican sunflower blossom, we decided try to come to the aid this and any other hardy survivor of the freeze.  Since we have not enjoyed great success attracting butterflies to commercial butterfly feeders, we decided to set out a couple of homegrown butterfly feeders.

        We immediately moved a pot containing several pineapple sage plants in full bloom to a spot near the dead Mexican sunflowers.  Talk about immediate gratification–within minutes a cloudless sulphur appeared and began nectaring on the pineapple sages’ long, scarlet blossoms.

       Encouraged by our success we later positioned a couple of containers containing scarlet sage to spots around the yard.  Since we have not experienced another frost since that time, we have enjoyed watching cloudless sulphurs and gulf fritillaries visiting our homegrown feeders every day.

       Our ability to take this action was due to the fact that we grow a number of nectar plants in large containers.  Once we heard of the impending, hard freeze we moved pots containing pineapple and scarlet sage either up against the side of the house or inside our sunroom.

       We realize that providing food for a handful of butterflies after a frost killed most of their food supply means little to the populations of gulf fritillaries and cloudless sulphurs.  However, it means a lot to handful of butterflies that are benefitting from our efforts.  In addition, it has made us feel good.

PINEAPPLE SAGE IS GREAT FOR LATE SEASON HUMMERS AND MORE

        There are at least 60 species of salvias.  In addition, more than 50 cultivars of these popular plants are also available.  There are so many varieties of salvias available it is difficult for Georgia gardeners to decide which are best for their gardens.  If you are looking for salvia that blooms late from late summer into fall and provides nectar for hummingbirds, butterflies, native bees and other pollinators, I recommend you plant pineapple sage (Salvia elegans).

       This plant is native in Central America.  Here in Georgia it is  either a tender perennial or annual.  While it is susceptible to cold weather, some gardeners report that when mulched it can survive winter temperatures that plummet as low as 5˚F.

       One of the things I like about pineapple sage is that it begins blooming late in the summer and will continue producing blooms until the frost ends its growing season.  Consequently, in autumn, it is providing nectar when it is often a scarce commodity.

       Although ruby-throated hummingbirds have been gone from our yard for weeks, they did nectar at the plants long tubular-shaped blooms before they left.  However, the main beneficiaries of its nectar are now cloudless sulphur and sleepy orange butterflies, and native bees.

       Over the years, many folks that have been lucky enough to attract wintering hummingbirds have told me that rufous hummingbirds frequent the pineapple sage’s striking red blossoms.

       Pineapple sage grows to be 3-4 feet tall and 3-4′ wide.  It seems to prosper in spots bathed in both morning and afternoon sunshine.  Pineapple sage also needs frequent watering. In addition, they do best in rich, well-drained soil.

       The plants are easily propagated from cuttings.  Young plants should be transplanted as soon as the threat of frost has passed in your neck of the woods.

       As you might expect, the blooming period in the southern half of the state is considerably long that it is in Middle and North Georgia.  However, regardless of how long is blooms, when it is blooming it provides pollinators with a valuable source of food while at the same time adding beauty to our yards.

                 Cloudless Sulphur on Pineapple Sage

       My wife and I bring our potted plants inside in the winter.  The pineapple sage growing in our yard is mulched during the winter.

       With the freezing weather forecast during the next several days, it is time for us to protect our pineapple sage before it is too late: This is one plant we do not want to lose.

THE WIND CAN AFFECT MONARCH WATCHING

       Monarch watching has been downright abysmal around my home.  As of October 15, only one monarch had made an appearance at the Johnson Homestead.  However, the next day monarchs were seen twice in my yard.  The first sighting took place in early afternoon.  Then just before dark, I spotted a monarch drifting across the bird feeding area located in front of my office.  While I will never know for sure, it seemed it was looking for a place to roost for the night. 

       I suspect the monarchs had been riding the wind.  Yesterday a cold front swept through Middle Georgia.  This leads me to believe this was the case because it is a fact that during their fall migration monarchs often catch rides on northerly winds found along the leading edges of approaching cold fronts.  If these winds are blowing in the direction the butterflies want to go, the butterflies can fly long distance without having to expend a lot of stored fuel.  When this occurs monarchs are often seen making their way southward  for several days after the leading edge of the cold front has left your us far behind.

       On the other side of the coin, if the north winds are too strong, monarchs are known to fly so high in sky it is impossible for us to see them as they wing their way over our yards.

       Conversely, when the prevailing winds are blowing from the south, they tend to hang around and forage for nectar before resuming their migration.  This situation often provides us with some of our best monarch watching opportunities.

     

BACKYARD SECRET–BUTTERFLY WINGS ARE ACTUALLY TRANSPARENT

       It is hard to believe that the colorful insects that are often called flying flowers possess wings that are actually transparent.  Let me explain.

       It seems that butterfly wings are composed of a rugged material called chitin.  This same substance comprises the exoskeletons of all butterflies.  The thin layers of chitin found in a butterfly wing is actually transparent.  The colors seen in a butterfly’s wings stem from literally thousands of loosely attached tiny scales covering each wing.  Some 600 scales/sq. millimeter blanket the surfaces of the wings of some butterflies.  These scales contain pigments that reflect light.  The colors we see on the wings of the butterflies we spot flitting around our yards are the result of the types of scales and the amount and kinds of pigments they possess.

       Butterflies constantly lose scales as they age.  Consequently, some of the individuals of the same species we spot are less colorful than others.  When we see pale versions of species, we know these individuals are much older than those that display more iridescence and color.  In some cases, butterflies lose so many scales it is difficult or even impossible to identify them.

      

BUTTERFLY SECRET REVEALED

       The red-banded hairstreak is one of our smallest and seemingly most fragile butterflies.  Whenever I am fortunate enough to spot one of these tiny flying jewels, I realize that they have little chance of surviving the attack of a predator.  Without the benefit of speed or camouflage, they must rely on deception to avoid becoming a meal.

       The red-banded is one of a handful of hairstreaks that inhabit my yard.  Like the other hairstreaks, the red-banded’s hindwings bear short, slender extensions often referred to as tails or hairs.  In addition, two black spots adorn the trailing edge of each hindwing.  These spots serve as false eyes.  They, along with the projections that look like antennae, are keys to the red-banded hairstreak’s ability to deter predators.

       Whenever you look at a red-banded hairstreak perched on a leaf or flower you will notice its hindwings are in constant motion.  When one wing goes up other goes down.  The constant movement of the butterfly’s wings makes a bird believe it is looking at the head of the insect.  As such, when it attacks what it perceives to be the head of its prey, it ends up with nothing more than pieces of the insect’s wings.  This gives the butterfly the opportunity to fly away without suffering a lethal wound.

       However, Dr. Andrei Sourakov, a scientist with the University of Florida, has conducted experiments that strongly suggest that the hairstreak’s ruse might actually serve to protect it from attacks of another predator known as the jumping spider.  When the biologist placed hairstreaks that had their false heads cut off in the same container with jumping spiders, the spiders always attacked the butterflies’ true heads.  However, when he placed hairstreaks possessing complete wings in a container containing the predators, the spiders only attacked the butterfly’s false heads.

       I am certain the hairstreaks’ behavior dupes birds into striking at their false heads too.  However, due to the jumping spider’s greater abundance, it makes sense, that the deception aids the butterflies from fooling spiders more than birds.

       This is just another case where research is forcing us to question our long-held beliefs concerning the natural world.