Friday, March 19, 2021

When Good Intentions Have Devastating Results

The following article is published here by permission of

Carson made a critical mistake and a lot of people died as a result. 

Mosquito on flesh

On Jan. 24, 2017, PBS aired a two-hour special on Rachel Carson, the mother of the environmental movement. Although the program crossed the line from biography to hagiography, in Carson’s case, the unbridled praise was well deserved – with one exception.

Rachel Carson was an American hero. In the early 1960s, she was the first to warn that a pesticide called DDT could accumulate in the environment, the first to show that it could harm fish, birds, and other wildlife, the first to warn that its overuse would render it ineffective, and the first to predict that more natural means of pest control – like bacteria that killed mosquito larvae – should be used instead.

Unfortunately, the PBS documentary neglected to mention that in her groundbreaking book, Silent Spring, Carson had made one critical mistake – and it cost millions of people their lives.

Carson's Literary Acclaim

On Nov. 1, 1941, Rachel Carson published her first book, Under the Sea-Wind. Although written for adults, the book had a child-like sense of wonder. Under the Sea-Wind told the story of Silverbar, a sanderling that migrated from the Arctic Circle to Argentina; Scomber, a mackerel that traveled from New England to the Continental Shelf; and Anguilla, an American eel that journeyed to the Sargasso Sea to spawn. “There is poetry here,” wrote one reviewer.

Most people under the age of 40 have never heard of Rachel Carson, but in the 60s, almost every American knew her name.

In July 2, 1951, Carson published her second book, The Sea Around Us. Two months later, The Sea Around Us was #1 on the New York Times bestseller list, where it remained for 39 weeks: a record. When the dust settled, The Sea Around Us had sold more than 1.3 million copies, been translated into 32 languages, won the National Book Award, and been made into a movie. Editors of the country’s leading newspapers voted Rachel Carson “Woman of the Year.”

In October 1955, Carson published her third book, The Edge of the Sea, a tour guide for the casual adventurer. The New Yorker serialized it, critics praised it and the public loved it: more than 70,000 copies were sold as it rocketed to #4 on the New York Times bestseller list.

Today, most people under the age of 40 have probably never heard of Rachel Carson. But in the early 1960s, almost every American knew her name.

Demonizing DDT

On Sept. 27, 1962, Rachel Carson changed her tone. Her next book, Silent Spring, which she called her “poison book,” was an angry, no-holds-barred polemic against pesticides: especially DDT.

The first chapter of Silent Spring, titled “A Fable for Tomorrow,” was almost biblical, appealing to our sense that we had sinned against our Creator. “There was once a town in the heart of America where all life seemed to live in harmony with its surroundings. Then a strange blight crept over the area and everything began to change… the cattle and sheep sickened and died… streams were lifeless… everywhere there was the shadow of death.”

DDT was an effective weapon against an infection that has killed more people than any other: malaria. 

Birds, especially, had fallen victim to this strange evil. In a town that had once “throbbed with scores of bird voices there was now no sound, only silence.” A silent spring. Birds weren’t alone in their suffering. According to Carson, children suffered sudden death, aplastic anemia, birth defects, liver disease, chromosomal abnormalities, and leukemia – all caused by DDT. And women suffered infertility and uterine cancer.

Carson made it clear that she wasn’t talking about something that might happen – she was talking about something that had happened. Our war against nature had become a war against ourselves.

In May 1963, Rachel Carson appeared before the Department of Commerce and asked for a “Pesticide Commission” to regulate the untethered use of DDT. Ten years later, Carson’s “Pesticide Commission” became the Environmental Protection Agency, which immediately banned DDT. Following America’s lead, support for international use of DDT quickly dried up.

The Global Killer

Although DDT soon became synonymous with poison, the pesticide was an effective weapon in the fight against an infection that has killed – and continues to kill – more people than any other: malaria.

By 1960, due largely to DDT, malaria had been eliminated from 11 countries, including the United States. As malaria rates went down, life expectancies went up; as did crop production, land values, and relative wealth.

Tens of millions of people have died from malaria unnecessarily. 

Probably no country benefited from DDT more than Nepal, where spraying began in 1960. At the time, more than two million Nepalese, mostly children, suffered from malaria. By 1968, the number was reduced to 2,500; and life expectancy increased from 28 to 42 years.

After DDT was banned, malaria reemerged across the globe:

  • In India, between 1952 and 1962, DDT caused a decrease in annual malaria cases from 100 million to 60,000. By the late 1970s, no longer able to use DDT, the number of cases increased to 6 million.
  • In Sri Lanka, before the use of DDT, 2.8 million people suffered from malaria. When the spraying stopped, only 17 people suffered from the disease. Then, no longer able to use DDT, Sri Lanka suffered a massive malaria epidemic: 1.5 million people were infected by the parasite.
  • In South Africa, after DDT became unavailable, the number of malaria cases increased from 8,500 to 42,000 and malaria deaths from 22 to 320.

Since the mid-1970s, when DDT was eliminated from global eradication efforts, tens of millions of people have died from malaria unnecessarily: most have been children less than five years old. While it was reasonable to have banned DDT for agricultural use, it was unreasonable to have eliminated it from public health use.

Costing Lives

Environmentalists have argued that when it came to DDT, it was pick your poison. If DDT was banned, more people would die from malaria. But if DDT wasn’t banned, people would suffer and die from a variety of other diseases, not the least of which was cancer. However, studies in Europe, Canada, and the United States have since shown that DDT didn’t cause the human diseases Carson had claimed.

The only type of cancer that increased in the United States during the DDT era was lung cancer. 

Indeed, the only type of cancer that had increased in the United States during the DDT era was lung cancer, which was caused by cigarette smoking. DDT was arguably one of the safer insect repellents ever invented – far safer than many of the pesticides that have taken its place.

Carson’s supporters argued that, had she lived longer, she would never have promoted a ban on DDT for the control of malaria. Indeed, in Silent Spring, Carson wrote, “It is not my contention that chemical pesticides never be used.” But it was her contention that DDT caused leukemia, liver disease, birth defects, premature births, and a whole range of chronic illnesses.

An influential author can’t, on the one hand, claim that DDT causes leukemia (which, in 1962, was a death sentence) and then, on the other hand, expect that anything less than that a total ban of the chemical would result.

In 2006, the World Health Organization reinstated DDT as part of its effort to eradicate malaria. But not before millions of people had died needlessly from the disease.

Reprinted from The Daily Beast.

Paul A. Offit
Paul A. Offit


Paul A. Offit is a professor of pediatrics and director of the Vaccine Education Center at the Children’s Hospital of Philadelphia. He is the author of Pandora’s Lab: Seven Stories of Science Gone Wrong (National Geographic Press, April 2017). 

This article was originally published on Read the original article.

Thursday, March 18, 2021

Choice Plants For The Coastal Landscape

A stroll on Hilton Head Island reveals a short list 

Hilton Head coastline

Coastal landscapes are very demanding on plants. Strong sunlight, wind, sandy soil, and salt air require much. A recent stroll at Sea Pines, Hilton Head provided a short list of species that thrive in such conditions, at least in the Deep South.

Here’s what I found:

Nerium oleander flowers and leaves

Usually known only as "oleander", its origins are unknown, though the Mediterranean region is likely. Nerium is usually grown in tropical and subtropical environments as a free-form shrub. It blooms all summer long. Flowers in colors ranging from white to red are fragrant. Variegated foliage is available. Maintenance requirements are extremely low.

Ficus pumila
Creeping Fig - Ficus pumila

Creeping Fig is an elegant vine that does it's job gracefully, producing a luxuriant, evergreen covering where it is needed. Perhaps you have seen Creeping Fig covering garden walls in lovely cities of the Deep South. Clinging closely, it lends dark green softness to all kinds of structures.

Cycas revoluta
Cycas revoluta - Sago Palm

Cycas revoluta - aka Sago Palm - is not a palm at all, but a member of the ancient Cycadaceae family. It's native to Japan, and is comfortable in warm temperate and subtropical regions. Sago is popular throughout the South, in botanical gardens and landscapes.

Asparagus densiflorus 'Myersii'
Asparagus densiflorus 'Myersii' - Asparagus fern

This member of the Asparagaceae family is not a fern, but an asparagus. It's hardy in USDA climate zones 9-11. While often used as a container plant, it also does well in the landscape, provided that it's protected during freezing weather. Though this particular plant was photographed in the sun, I've found that it has better color if grown in partial shade.

Rosmarinus officinalis 'Prostrata'
Salvia rosmarinus 'Prostratus' aka Rosemary

As taxonomists would have it, Rosmarinus is now classified as a Salvia. But whatever. It's a fine plant for the coastal garden. Its Latin name is even derived from its native habitat meaning "dew of the sea." Rosemary is native to the Mediterranean region. Some varieties are susceptible to frost, but it thrives in heat and well-drained soil. Beside its ornamental use, rosemary is well-known for its culinary value.

Gelsemium sempervirens
Gelsemium sempervirens - Carolina Jessamine

As I write this in mid-March, this gorgeous garland of yellow is in full bloom. Its range is from Virginia to Texas and southward through Mexico. Carolina Jessamine is one of my favorite flowering vines. It can be grown high or low, over your mailbox or under it. The deep yellow garlands in the trees drop lovely blossoms on the forest floor below, golden mantles drape garden walls, and the fragrance is wonderful.

Cyrtomium falcatum
Cyrtomium falcatum - Holly Fern

This glossy, evergreen beauty is tough as nails. Its beauty is irresistible. Use if for ground cover, borders, accents. Gardeners in colder climates can grow it as a house plant.

Aspidistra elatior
Aspidistra elatior - Cast-Iron Plant

True to its name, Aspidistra is beyond tough. As I wrote in an earlier article, "In dry, thin soil under trees they thrive.  Stuffed in neglected pots, they wait for someone to come and dribble a little water; often just a styrofoam cup of melted ice and lemon slice.  Yellowed by too much sun, ragged from neglect, they persist.  Often they are as neglected indoors, or worse." But when grown in shade with a bit of care, Aspidistra lends a wonderful tropical appearance to the home and landscape.

Nephrolepis cordifolia
Nephrolepis cordifolia - Erect Sword Fern

Several species go by the common name of Sword Fern. Best go by the botanical name if you're looking for this one. Nephrolepis cordifolia is a very successful evergreen ground cover fern for southern and coastal gardens. So successful, in fact, that some folks consider it to be invasive. But, hey, it covers ground. Isn't that what ground covers are supposed to do?

Nandina domestica
Nandina domestica - Heavenly Bamboo

Nandina is a rather common landscape shrub that's hardy from UDSA Climate Zone 6 through 11. It's native to Japan. Evergreen foliage often turns to scarlet shades in winter, and new foliage may be burgundy in color. Berries are usually red, though other colors appear on the market. Dwarf forms are available. It's about as easy to grow as anything you can imagine. Fairly fertile soil and a little water is all it needs. Grow it in full sun or partial shade.

Daniella tasmanica
Dianella tasmanica - Flax Lily

Dianella is a fairly new plant on the market. It might be named for the Greek goddess, Diana, or another Diane. I don't know. At any rate, it's native to Tasmania and southeastern Australia. Its small, blue flowers are quite charming. The variegated form is my favorite. Dianella is evergreen, thrives in sun or partial shade, dry soil, and warmer climate zones - specifically USDA Climate zones 9 through 11. 

Hedera algeriensis - Algerian ivy

Algerian Ivy, also known as Hedera algeriensis, Hedera canariensis, Hedera canariensis var. algeriensis, Algerian Ivy, Canary Island Ivy, North African Ivy, or Madeira Ivy is a favorite of gardeners in the South. It thrives in warmer climates. Large, glossy, evergreen leaves cover ground nicely. It's not limited to use as a ground cover, however. It will easily cover fences, balustrades, and trellises, too. Deer won't eat it. Algerian Ivy is salt tolerant and drought tolerant, too.

Trachelospermum asiaticum
Asiatic Jasmine

Asiatic Jasmine (Trachelospermum asiaticum) vines form a dense, glossy, evergreen mat, that suppresses weeds, making it an ideal ground cover. It thrives in full sun to full shade in USDA climate zones 7 to 9, and tolerates a wide variety of soil types. It's drought tolerant, deer and rabbit resistant. It's a ground cover that you're bound to love.

This is by no means an exhaustive list of appropriate plants for the coastal garden, but I figure it's about all that the normal adult's attention span will tolerate. I'll probably post an additional list in the future.

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Friday, March 5, 2021

Social Distancing Is For The Birds, Too.


Sick pigeon

As much as we loathe social distancing, it can be a good thing. Disease transmission is diminished when we insist on a bit more personal space. This is true even for the common cold. The principle holds for people and for the birds.

Birds can carry diseases, too. According to Medical News Today, “birds and their droppings can carry over 60 diseases.” While bird diseases certainly pass from bird to bird, some can even be transmitted to humans. And it’s not just avian flu that we can worry about. Others include:

  • “Histoplasmosis is a respiratory disease that may be fatal. It results from a fungus growing in dried bird droppings.
  • Candidiasis is a yeast or fungus infection spread by pigeons. The disease affects the skin, the mouth, the respiratory system, the intestines and the urogenital tract, especially the vagina. It is a growing problem for women, causing itching, pain and discharge.
  • Cryptococcosis is caused by yeast found in the intestinal tract of pigeons and starlings. The illness often begins as a pulmonary disease and may later affect the central nervous system. Since attics, cupolas, ledges, schools, offices, warehouses, mills, barns, park buildings, signs, etc. are typical roosting and nesting sites, the fungus is apt to found in these areas.
  • St. Louis Encephalitis, an inflammation of the nervous system, usually causes drowsiness, headache and fever. It may even result in paralysis, coma or death. St. Louis encephalitis occurs in all age groups, but is especially fatal to persons over age 60. The disease is spread by mosquitoes which have fed on infected house sparrow, pigeons and house finches carrying the Group B virus responsible for St. Louis encephalitis.
  • Salmonellosis often occurs as "food poisoning" and can be traced to pigeons, starlings and sparrows. The disease bacteria are found in bird droppings; dust from droppings can be sucked through ventilators and air conditioners, contaminating food and cooking surfaces in restaurants, homes and food processing plants.
  • E.coli. Cattle carry E. coli 0157:H7. When birds peck on cow manure, the E. coli go right through the birds and the bird droppings can land on or in a food or water supply.

"Besides being direct carriers of disease, nuisance birds are frequently associated with over 50 kinds of ectoparasites, which can work their way throughout structures to infest and bite humans. About two-thirds of these pests may be detrimental to the general health and well-being of humans and domestic animals. The rest are considered nuisance or incidental pests.

A few examples of ectoparasites include:

  • “Bed bugs (Cimex lectularius) may consume up to five times their own weight in blood drawn from hosts which include humans and some domestic animals. In any extreme condition, victims may become weak and anemic. Pigeons, starlings and house sparrows are known to carry bed bugs.
  • Chicken mites (Dermanyssus gallinae) are known carriers of encephalitis and may also cause fowl mite dermatitis and acariasis. While they subsist on blood drawn from a variety of birds, they may also attack humans. They have been found on pigeons, starlings and house sparrows.
  • Yellow mealworms (Tenebrio molitor), perhaps the most common beetle parasites of people in the United States, live in pigeon nests. It is found in grain or grain products, often winding up in breakfast cereals, and may cause intestinal canthariasis and hymenolespiasis.
  • West Nile Virus while West Nile is technically not transmitted to humans from birds, humans can get infected by the bite of a mosquito who has bitten an infected bird. The obvious lesson is that the fewer birds there are in any given area, the better. This translates into a smaller chance of an infected bird in that area, a smaller chance of a mosquito biting an infected bird and then biting a human.”

So, what can we do about it?

Medicines are out of the question. How can we treat wild birds? The populations are too great, and indiscriminate broadcasting can do more harm than good.

Sensible steps can be taken to slow disease transmission. Here are a few examples:

  • Keep an eye out for birds that seem lethargic, have fluffed feathers, or won’t fly away when approached. They might be ill. Report them to your regional Department of Natural Resources or local animal control office. Tufts Wildlife Clinic has more to say about this.
  • Don't handle sick birds.
  • Provide several feeders located in different areas so fewer birds will congregate together. 
  • Clean and disinfect bird feeders and bird baths regularly with a 5% solution of bleach.
  • Use separate brushes, scrubbers and other tools for cleaning them. Don’t use them for other purposes, and don’t bring them into the house.
  • Provide fresh food, throwing away any that seems rancid or moldy.
  • Feed only as much as the birds will consume in a couple of days.
  • Move your bird feeders occasionally so that droppings, seed hulls and discarded food doesn’t accumulate beneath them. Rake and disperse the debris.
  • Change water in bird baths every couple of days.
  • Wear a mask when cleaning bird feeders, baths, and cleaning under them. I know you’re tired of being told to wear a mask, but you don’t want to breath airborne disease spores, if any are present.

Hopefully, a bit of care will help to mitigate the spread of disease among us and our feathered friends.

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Thursday, March 4, 2021

Homes For The Buzzin' Bees

"There ain't no words for the beauty, the splendor, the wonder."

Photo by Dominicus Johannes Bergsma/Wikimedia Commons.
Photo by Dominicus Johannes Bergsma/Wikimedia Commons.

Gardening is not just about growing pretty flowers and delicious foods. It’s also about enjoying nature, and some of the most fun to watch are the little flying creatures that hover and dart about. There are, of course, the butterflies, honeybees and bumblebees. But most interesting – to me, anyway – are the tiny little bees. Some are brown. Some black. Some iridescent. These are the native bees, sometimes called sweat bees, cutter bees, or mason bees. They are essential to good pollination. It feels good to provide a place where they like to hang around.

It’s well-known that flowers provide bees with food. That’s they real reason they’re there. Their acts of pollination are actually happy accidents that they perform while brushing against pollen in their quests. 

But apart from planting native wildflowers, we can also attract them by providing homes. Many of us think of bee hives when we think of homes for bees...or hair.

I let it fly in the breeze

And get caught in the trees

Give a home for the fleas in my hair

A home for fleas

A hive for the buzzin' bees

A nest for birds

There ain't no words

For the beauty, the splendor, the wonder

Of my...

Hair, hair, hair, hair…

-The Cowsills

You know where I'm coming from. But that’s not it. Those little bees nest in surprising little hideaways like tunnels excavated by beetles, crevices, broken branches, holes in the ground, rotten logs, abandoned lumber, old reeds and hollowed-out stems. Some of which we can provide with ease. 

Osmia cornifrons at nest's entrance.
Photo by Beatriz Moisset/Wikipedia Commons

Here are some simple ideas:

  • Find old logs, and drill deep, horizontal holes of various diameters – between 1/16 inch and 1/2 inch – in the ends.
  • You can do the same with dead trees, but don’t drill into living ones.
  • Gather hollow reeds about 6” to 8” long. Miscanthus spp., Arundo donax and pampas grasses are good examples. Bundle them together, and tie with twine. Place them horizontally around the garden in clay pots, or hang them under the eaves of your tool shed to keep them dry. 
  • If you’re ambitious, construct little structures resembling bird houses with the fronts removed, and stuff them with the reeds.
  • You can do the same with lengths of old Rubus canes, Sambucus stems or Chinaberry (Melia azedarach) sticks.
  • Bamboo canes will serve well, and are longer lasting, but the segments might need to be reamed out with a drill to make the nesting spaces deep enough.
  • If you intend to use old lumber, avoid pressure-treated woods which could be toxic to bees.

These are things that you can do with your kids, teaching them something about nature and to be kind to creatures.

To be sure, there are purists out there who would say, “Oh NO! That’s not the way to do it! What a terrible idea.” But, frankly, I’ve never known bees to follow all the rules. Some drill holes in my house, stored lumber, and even try to nest in my electrical outlets. I say, “Don’t stress out about it.” Have fun. Do good.

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Wednesday, March 3, 2021

How To Repair Trees and Shrubs After Snow Damage

 A Do-It-Yourself Guide

Photo by Nico from Pexels.

Heavy snow storms can cause a lot of damage to trees and shrubs. They usually recover quite naturally, but sometimes need some help. Here are some helpful first aid tips for trees.

Broken limbs and branches may be repaired by setting them as a doctor would a broken bone. If the breaks are fairly clean and fresh, the broken ends may be put back in place, tightly bound, properly supported, and allowed to grow together. Here’s how:

  • Begin the repair immediately. If the damaged tissue has dried after several days or even hours of separation, it’s unlikely to repair itself.
  • Line up the broken ends, giving special attention to all of the outer edges for they contain the cambium tissue. Cambium is responsible for repairing and replacing damaged cells, and forming bark. If the edges don’t meet, they won’t grow together properly.
  • Wrap the mend tightly with grafting tape.
  • Spread or spray tree wound dressing on the repaired area to form a moisture barrier. (Whether this is actually necessary is a subject of debate within the horticultural community.)
  • Support the break with wooden splints along the sides, above and below, tightly wrapped. 1” x 2”grade stakes or tree stakes of sufficient length are good for larger branches. Longer limbs and branches might need to be propped up from the ground with 2” x 4” timbers. Stakes and timbers can be purchased at a local hardware store. Grafting tape can be purchased online or from a garden center.
  • Leave everything in place for at least one growing season, and possibly two. But inspect the mend every few weeks to make sure that it isn’t restricting (i.e. choking) the branch as it thickens.

After all that, the grafting might not be successful, especially if the break was ragged or dirty. Limbs seldom break evenly. 

Image by <a href=";utm_medium=referral&amp;utm_campaign=image&amp;utm_content=91996">JamesDeMers</a> from <a href=";utm_medium=referral&amp;utm_campaign=image&amp;utm_content=91996">Pixabay</a>

Jagged edges present real problems, for it’s difficult to match the broken ends for a strong repair. If so, remove the limb behind the break, if possible. New sprouts may form to replace the broken limb. (Not all species are accommodating.) Aesthetically, this works best on younger branches. Older limbs might not sprout at all, and if they do, they might look like crap. If that’s the case, you might be better off removing the limb entirely. Here’s how:

  • Identify the “collar” where the limb joins the trunk. It’s a swollen area that surrounds the base of the limb at the trunk. This structure contains all the regenerative tissue needed to heal over the cut.
  • Cut the limb cleanly and evenly at the outer edge of the collar.
  • Trim off any ragged edges.
  • Trim off the stub, if you cut too far out. If a stub is left poking out, the tissue can’t grow over the wound. The stub will die, and the necrosis (death) will proceed into the trunk itself, weakening the whole plant, and eventually causing its death. If the collar is removed, the wound will take longer to heal, if it heals at all.
  • Apply wound dressing if it makes you feel better.
Proper position for pruning tree limb stub
Proper place to cut tree limb stub

Necrotic tree limb stub
Necrotic tree limb stub

If new sprouts emerge from the cut area, one might be chosen to replace the missing branch. Here’s how:

  • Remove the weakest sprouts when they are fresh and recently emerged. (This might require doing more than once.) Rub or pinch them off with your fingers.
  • Use a small weight or weights to train the chosen sprout into the proper position as it grows.
  • Better still, use a limb spacer or spreader to achieve the proper angle. You can make them yourself from thin strips of plastic or wood lath, cut to the desired length, and notched at both ends to hold them in place.

If a load of snow has bent the tree or shrub – this is usually the case with upright evergreen junipers and arborvitae – it is more easily repaired. Remove the snow, wrap some rope or soft twine around the plant, and tie it upright. If snow or ice cannot be removed without doing damage to the branches, leave it alone, pray that no more snow falls, then wrap the plant after snowmelt.

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