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Supermarket bargains and food waste

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Food waste is a major global problem.  The UN estimates that one third of all food goes to waste.  Apart from the fact that this is happening in a world where many people don’t have enough to eat, food waste is both an economic and a climate problem.

Researchers from the University of Copenhagen and Southern Methodist University investigated how different types of grocery sales strategies affect people’s shopping and food waste.  The result was that bulk offers increase food sales by nearly 20%, but they also lead to increased food waste in people’s homes.

The study analyzed over 43,000 purchases of fresh vegetables in eight Swedish supermarkets.  When customers were offered “two-fer” offers, they bought significantly more than when only single items were available.  The attraction of a special offer can be strong.  But, according to a follow-up survey, food from bulk offers ended up in the trash more often.  People thought they were saving money, but often ended up buying more than they can eat.

The researchers tested two strategies for reducing overbuying.  One was to make the actual savings explicit by displaying the regular price next to the offer.  The second was to put a friendly reminder on the offer sign along the lines of “I’d love to come home with you if you eat me.”  Both of these approaches resulted in reduced sales of 9-11% compared to the original volume offer despite the sale price remaining the same. 

Clearly, small changes in marketing can make a big difference.  Supermarkets play a big role in the occurrence of food waste and they have the ability to help nudge consumers into better behavior.

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Good deals – bad for the climate: Supermarket volume discounts lead to food waste

Photo, posted November 13, 2006, courtesy of Josh Hallett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More trouble for bees

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Honeybees are a critical resource for American agriculture.  The western honeybee, Apis mellifera, pollinates more than 130 types of nuts, fruits, and vegetables, adding up to $15 billion worth of crops every year.  Honeybee health has been harmed by a combination of factors:  weather extremes, habitat loss, pesticides, and disease.  One of the biggest problems has been a parasite called varroa destructor, which is a Southeast Asian mite that first entered the United States in the 1980s.  The mites spread viruses to the bees.

The past year has been a particularly bad one for the bees.  Nearly 56% of managed honeybee colonies died off in the past year, the worst rate since annual reporting began in 2011. 

Even while American beekeepers seek solutions to the varroa problem, a potentially worse threat is on the horizon.  Another Southeast Asian mite, tropilaelaps, has been making its way across Asia and into Europe. If these mites arrive in North America, the results would be disastrous, wreaking havoc on honeybees and ravaging the nation’s food supply.

Western honeybees are the only honeybee species that is not native to Southeast Asia.  As the cradle of development of the bees, Southeast Asia has given rise to a bounty of parasites and viruses that are dependent upon them.  In turn, bees native to that region have had time to evolve defenses against these pathogens.  Western honeybees have not.

Beekeepers and authorities are taking measures to delay or prevent the arrival of tropilaelaps mites.  The stakes are very high.

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After Devastating Winter Losses, Another Threat Looms for U.S. Beekeepers

Photo, posted April 14, 2013, courtesy of Paul Rollings via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Forest-based agroforestry

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Tree plantings have become a go-to climate solution for governments and conservation groups due to the carbon-storing potential of trees.  While planting new trees on open farmland would help capture additional carbon, a new study led by scientists from Yale School of the Environment suggests a powerful alternative: forest-based agroforestry.

Instead of clearing land for crops or starting fresh with new trees, forest-based agroforestry (or FAF) brings agriculture into existing forests.  Think fruits, nuts, and medicinal plants, for example, grown sustainably under a forest canopy – all while maintaining biodiversity and storing carbon.

According to the researchers, human activity in forests is often seen as harmful. But for thousands of years, Indigenous and local communities have managed forests in ways that actually strengthen them.

The study, which was recently published in the journal Nature Climate Change, found that FAF not only rivals tree planting in terms of climate benefits, but it can also generate income and support cultural practices tied to the land.

Despite these benefits, forest-based agroforestry receives far less funding and policy support due to two key misconceptions. It’s frequently confused with industrial systems focused on global commodity crops, and results from tropical regions are wrongly assumed to apply to temperate and boreal forests.

The researchers recommend including FAF in agroforestry policies, clearly distinguishing it from harmful industrial practices, and expanding research on FAF in temperate and boreal regions to guide better land management.

Forest-based agroforestry appears to be a natural climate solution hiding in plain sight.

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Agriculture in Forests Can Provide Climate and Economic Dividends

Photo, posted May 8, 2023, courtesy of Preston Keres / USDA Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Extending the shelf life of produce

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More than 30% of the world’s food is lost after it has been harvested.  That’s enough to feed more than a billion people.  Much of that loss is fruits and vegetables that go bad before they can be eaten.

Refrigeration is the most common way to preserve foods, but the energy and infrastructure required is not always available, especially in less affluent regions of the world.

Researchers at MIT and Singapore-based collaborators have demonstrated that they can extend the shelf life of harvested plants by injecting them with melatonin using biodegradable microneedles.

Silk microneedles are tiny, nontoxic, and biodegradable and represent a means of delivering nutrients to plants without triggering a stress response.

Melatonin is a natural hormone that plants already use.  Injecting it was shown to extend vegetables’ shelf life.  The tests used pak choy, an important Asian crop that is very perishable.  Untreated plants at room temperature yellowed within two or three days.  In contrast, treated plants stayed green for five days.  Overall, treated plants retained saleable value for 8 days.  Refrigerated plants had their shelf life extended considerably as well.  However, the most significant value of the technique is that it could enhance the shelf life of perishable produce like pak choy without needing access to refrigeration.

The dose of melatonin delivered to the plants is so low that it is fully metabolized by the crops, so it would not significantly increase the amount normally present in the food.  People would not ingest more melatonin than usual.  The researchers believe that their technique should work with all kinds of produce.

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A new technology for extending the shelf life of produce

Photo, posted May 6, 2010, courtesy of Jessica Spengler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Advantages of vertical farming

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Vertical farming has been increasingly used for leafy greens like lettuce and kale, as well as for herbs and a few fruits like strawberries and tomatoes.  A recent study by the Technical University of Munich has investigated the use of vertical farming for a much broader range of foods.  The study looked at the positive effects of vertical farming on both yield and environmental impact.

Traditional agriculture can reach its limits as a result of extreme weather events or in areas of high population density and resultant high demand.   With vertical farming, food can be grown close to consumers independent of weather and can make very efficient use of space.

The Proteins4Singapore study investigated the potential of a 10-layer vertical farming system cultivating crops, algae, mushrooms, insects, fish, and cultivated meat.  Many of these things are not currently part of many people’s diets.  But these foods can increase the protein yield per cultivation area nearly three hundredfold for crops and 6,000-fold for mushrooms and insects. 

Mushrooms and insects are examples of foods that require little light and cultivating them reduces energy consumption and, therefore, associated costs.

The biggest challenges for controlled environment agriculture – which is what vertical farming is – are the high energy demands for cultivation and the social acceptance.  Some of the foods that are especially well-suited to vertical farming – such as algae and insects – are not generally accepted by many consumers.  Controlled environment agriculture can revolutionize food production, but it will take a combination of technological advances, policy initiatives, and public engagement.

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Vertical Farming to increase yields and reduce environmental impact

Photo, posted October 21, 2022, courtesy of Fred Miller / University of Arkansas System Division of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bananas and climate change

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Bananas are one of the most widely produced fruits globally, with more than 100 million tons grown every year.  They are a key export crop worth approximately $11 billion annually. Bananas are also a staple food in many tropical countries, playing a vital role in both the economies of these nations and in global food security.

The Cavendish variety of banana dominates commercial exports, accounting for nearly 47% of global production. However, the Cavendish banana is highly susceptible to diseases like Panama disease, prompting ongoing efforts to develop disease-resistant alternatives. The spread of these diseases is exacerbated by climate change, which alters growing conditions and weakens banana plants. Additionally, climate change poses further threats to the banana industry by impacting crop yields and distribution patterns.

In fact, a new study led by researchers from the University of Exeter in the U.K. has found that by 2080, rising temperatures will make growing bananas for export economically unsustainable in many regions of Latin America and the Caribbean.  Colombia and Costa Rica will be among the countries most negatively impacted as they are expected to become too hot for optimal banana cultivation. 

The study, which was recently published in the journal Nature Food, found that 60% of the regions currently producing bananas around the world will struggle to grow the fruit unless there are urgent interventions to tackle climate change.  The researchers propose several adaptation strategies, including expanding irrigation systems, developing heat- and drought-resistant banana varieties, and helping banana producers manage climate-related risks.

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Climate change threatens future of banana export industry

Photo, posted June 26, 2024, courtesy of JJ Musgrove via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Greenhouses and the environment

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The use of greenhouses around the world has been growing dramatically.  A new satellite mapping exercise estimated the total land area covered with permanent greenhouses at 3.2 million acres, which is an area the size of Connecticut.  More than half of this is in China, where the growth of greenhouses has been driven by the rapid urbanization of the country and by a more prosperous population increasingly consuming produce like tomatoes, cucumbers, peppers, and eggplants.

The intensive agricultural methods employed within greenhouses can be harmful to local environments because of overtaxing water supplies and by polluting rivers and soils with nutrients, pesticides, and plastic waste.  But the effects of vast areas of plastic coverings on local temperatures can be even more dramatic, and often beneficial.

There are so many plastic and glass roofs in many areas that they are reflecting sufficient amounts of solar radiation to cool local temperatures.  Greenhouse roofs increase the albedo – the reflectivity – of the land surface typically by a tenth.

All these greenhouses are just the tip of the albedo iceberg.  Many farms now temporarily cover crops with reflective plastic sheets.  If these coverings are included in the satellite survey, the total reflective area would be about ten times greater – roughly the size of New York State.

A study in Almeria, on the Mediterranean coast of Spain, which grows about 3 million tons of fruit and vegetables annually, determined the cooling effects of greenhouses.  Weather stations amid the greenhouses showed an average cooling of 1.3 degrees Fahrenheit compared with the surrounding area.

Greenhouses are an accidental and benign form of climate engineering. The cooling provided by greenhouses is similar to the effect of white roofs in urban areas. 

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Could the Global Boom in Greenhouses Help Cool the Planet?

Photo, posted September 6, 2017, courtesy of Lance Cheung / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic food packaging

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Reducing the use of plastic is an important environmental goal.  Plastic is made from fossil fuels and plastic pollutes the land and the oceans.  It is estimated that 40% of plastic waste comes from packaging.  Plastic packaging is extremely common in the supermarket and there is a growing desire to reduce its use.  But it isn’t that easy.

Plastic packaging works well to slow the decay of vegetables and fruit.  Its use results in less produce being tossed into the garbage, where it creates almost 60% of landfill methane emissions.  In fact, food is the most common material in landfills.  The average American family of four spends $1,500 a year on food that ends up uneaten and nearly half of all household food waste is fruits and vegetables.

Products like bagged salads, berries in plastic clamshells, and plastic sealed potatoes and cucumbers are popular with shoppers because they stay fresh longer.  They are popular with grocers because the items don’t have to be weighed.  But all these things result in plastic waste.  It is a tradeoff that is difficult to make between food quality and safety vs. the environmental harm caused by plastic.

There are a variety of alternatives to plastic packaging of food that are being explored.  They range from biodegradable, organic coatings that can take the place of plastic films, to cardboard and paper produce packaging. 

But practically, there is yet no affordable and biodegradable plastic alternative that keeps fruits and vegetables safe and fresh.  Solving the food packaging problem is not easy.

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So Much Produce Comes in Plastic. Is There a Better Way?

Photo, posted July 1, 2007, courtesy of Brian via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Support Pollinators | Earth Wise

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Pollinators of all sorts have been in decline for a while.  This is especially true of bees, bats, and monarch butterflies.  Without pollinators, fruits, vegetables, and other plants cannot provide their contributions to our food supply.  According to experts, about 30% of the food that ends up on our tables gets there because of pollinators.

Bees are the most efficient pollinators, but plenty of other insects do their share as well.  Butterflies and months, flies, beetles, and wasps all are good pollinators.  In addition to insects, birds and bats can also be pollinators. 

Entomologists at Texas A&M University have offered some science-based advice for homeowners who want to keep pollinators around and thriving during the summer months.

Pollinators need flowers that bloom at different times of the year.  So, home gardens should overlap blooms.  Native and drought-tolerant species are good additions to a garden or landscape.

Colorful gardens attract more pollinators because different pollinators are attracted to different colors.  Bumblebees like blues and purples; other bees are attracted to yellows and whites.  Butterflies like bright colors like oranges and pinks.

Plant flowers with different shapes and sizes because pollinators flower preferences come in all shapes and sizes.

Provide shelter for pollinators.  Houses for bees and other pollinators are available for purchase. Or people can make their own using plastic tubes.

And probably most importantly, go easy on pesticides.  If it is really necessary to apply pesticides, do it in the evening when most pollinators have called it a day.

Having a colorful garden with lots of variety is a fine addition to one’s home.  Beyond that, it is a valuable contribution to helping preserve essential pollinators.

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Top Five Tips For Supporting Pollinators This Summer

Photo, posted August 14, 2017, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Red Pandas And Climate Change | Earth Wise

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Red pandas are small mammals native to the mountainous forests of China, India, Nepal, Bhutan, and Myanmar.  Unlike their name suggests, they are not related to giant pandas.  In fact, red pandas are distant relatives of raccoons. Renowned for their tree-climbing abilities, red pandas live at moderately high elevations in the Himalayas where they forage widely for bamboo shoots and various fruits.

According to the International Union for the Conservation of Nature, red pandas are endangered.  Scientists estimate that there are less than 10,000 red pandas remaining in the wild today, and these numbers are continuing to fall. 

Habitat loss is the main threat to red panda’s survival.  Human expansion into the area, combined with the effects of climate change, has led to the fragmentation and loss of livable land.  Red pandas also face dangers from hunting and poaching.

According to new research recently published in the journal Landscape Ecology, human impacts are driving red pandas closer to extinction than previously thought.  Using GPS telemetry, a research team from the University of Queensland in Australia tracked red pandas in Nepal over a 12-month period.  The researchers found that human activities, such as infrastructure development, were causing red pandas to restrict their movements, which is further fragmenting their habitat and interfering with natural interactions between the animals. 

As the amount of wild forest dwindles, red pandas are being forced into situations where they must decide whether to live closer to predators or adapt to co-exist with humans.

The research team recommends minimizing human-induced disturbances in red panda habitats and to maintain habitat continuity in ecologically sensitive areas. 

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Red pandas face a fractured future

IUCN: Red Panda

Photo, posted November 27, 2016, courtesy of Mathias Appel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Disease in Cavendish Bananas | Earth Wise

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Cavendish bananas account for about half of global banana production and the vast majority of bananas entering international trade.  The plant is unable to reproduce sexually and instead is propagated via identical clones.  So, the genetic diversity of the Cavendish banana is exceedingly low. 

In 2008, Cavendish cultivars in Sumatra and Malaysia started to be attacked by Panama disease, a wilting disease caused by a fungus.  In 2019, Panama disease was discovered on banana farms in the coastal Caribbean region, its first occurrence in the Americas.  In the 1950s, Panama disease wiped out the Gros Michel banana, the commercial predecessor of the Cavendish.

Scientists at the University of Cambridge have found a novel way to combine two species of grass-like plants – which include bananas, rice, and wheat – using embryonic tissue from their seeds.  The technique allows beneficial characteristics, such as disease resistance, to be added to the plants.

Joining the shoot of one plant to the root of another to grow as one plant is known as grafting.  It was thought to be impossible to do with grass-like plants – called monocotyledonous  grasses – because they lack a certain tissue type in their stems.  But the new research, published in the journal Nature, showed it can be done with the plants in their earliest embryonic stages.

Cavendish bananas are sterile, so disease resistance can’t be bred into future generations.  But the grafting technique may provide a way to produce Cavendish banana plants that are resistant to Panama disease.  It may be possible to save an important food crop before it is too late.

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New grafting technique could combat the disease threatening Cavendish bananas

Photo, posted July 1, 2015, courtesy of Augustus Binu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wastewater And Ammonia | Earth Wise

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Ammonia is the second most produced chemical in the world.  More than half of it is used in agriculture to produce various kinds of fertilizer, to produce cotton defoliants that make cotton easier to pick, and to make antifungal agents for fruits.  Globally, ammonia represents more than a $50 billion a year market.

Current methods to make ammonia require enormous amounts of heat – generated by burning fossil fuels – to break apart nitrogen molecules so that they can bind to hydrogen to form the compound. Ammonia production accounts for about 2% of worldwide fossil energy use and generates over 400 million tons of CO2 annually.

Engineers at the University of Illinois Chicago have created a solar-powered electrochemical reaction that uses wastewater to make ammonia and does it with a solar-to-fuel efficiency that is 10 times better than previous comparable technologies.

The process uses nitrate – which is one of the most common groundwater contaminates – to supply nitrogen and uses sunlight to power the reaction.  The system produces nearly 100% ammonia with almost no hydrogen side reactions.  No fossil fuels are needed, and no carbon dioxide or other greenhouse gases are produced.  The new method makes use of a cobalt catalyst that selectively converts nitrate molecules into ammonia.

Not only is the reaction itself carbon-neutral, which is good for the environment, but if it is scaled up for industrial use, it will consume wastewater, thereby actually being good for the environment.  The new process is the subject of a patent filing and the researchers are already collaborating with municipal corporations, wastewater treatment centers, and others in industry to further develop the system.

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Combining sunlight and wastewater nitrate to make the world’s No. 2 chemical

Photo, posted August 29, 2018, courtesy of Montgomery County Planning Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Atmospheric Carbon Into Useful Materials | Earth Wise

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Plants have the ability to capture carbon dioxide from the atmosphere and incorporate it into leaves, fruits, wood, and other plant materials.  This beneficial process is mostly temporary, as much of this carbon dioxide from plant matter ends up back in the atmosphere through decomposition, or even burning.

Researchers at the Salk Institute have proposed a more permanent fate for captured carbon by turning plant matter into a valuable industrial material called silicon carbide.

In a recent study published in the journal RSC Advances, Salk scientists transformed tobacco and corn husks into silicon carbide and evaluated and quantified the benefits of the process.

The researchers used a previously reported method to transform plant matter into silicon carbide in three stages and carefully tracked the carbon utilization at each stage.

Stage one is growing the plants.  They used tobacco from seed, chosen for its short growing season.  Then the harvested plants are frozen, ground into a powder, and treated with chemicals including a silicon-containing compound.  Finally, the powder is subjected to a high-temperature process resulting in the production of silicon carbide.

Their analysis showed that much of the carbon sequestered by growing the plants could be preserved through the full process and the amount of energy required for the production of the silicon carbide (mostly from the high-temperature process) is comparable to current manufacturing processes for the material.

Permanently sequestering carbon from agricultural waste products by incorporating it into a valuable industrial material would be a valuable addition to strategies for reducing greenhouse gases in the atmosphere.

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Transforming Atmospheric Carbon Into Industrially Useful Materials

Photo, posted August 3, 2013, courtesy of AJ Garrison via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

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The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world.  In Mexico, the pads are known as nopales and are used in a variety of dishes.  The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops.  Cactus pear can be used for both human consumption and livestock feed.  As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear.  The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid.  There is enormous potential for planting cactus for carbon sequestration.  If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why Do Trees Change Color? | Earth Wise

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We had a particularly colorful fall in the Northeast this year.  Almost everywhere you looked, there were brilliant displays of yellow, orange, and red.  The colors of fall are a result of chemistry and environmental events that may have taken place many months in the past.

The color of leaves comes from 4 pigments whose effects are governed by photosynthesis.  The one that is actually used in photosynthesis is chlorophyll and it causes leaves to be green.  But when a tree begins to prepare for dormancy, it stops producing chlorophyll, the green pigmentation fades, and the other pigments that were already in the leaves become visible.

There are xanthoplylls, which are the yellow pigments that are seen the most in fall trees.  They are the same pigments that color egg yolks and sometimes parts of the human eye.  They are only produced by plants and appear in humans and animals only through consumption.

There are carotenes, which are the orange pigments found in fruits and vegetables, such as carrots, oranges, some bell peppers and squashes.

And there is anthocyanin, which is the pigment found in blueberries, blackberries, and red or violet roses.  Its color depends on the pH level of the plant; higher pH leads to darker color.  This is the pigment seen in red maples, black cherry trees, Shumard oaks, and more.  Only 10% of trees in temperate climates produce anthocyanin and its red pigmentation and most of those trees are in New England.

All these pigments serve purposes.  They help trees absorb light energy, prevent sun damage, and even regulate how much energy chlorophyll produces.

There are complicated chemical and environmental factors at play in fall foliage but when they come together like they did this year, it’s a magnificent spectacle.

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Why Do Trees Change Color?

Photo, posted October 17, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Essential Oils And Organic Crops | Earth Wise

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Essential oils are concentrated liquids extracted from plants.  They are called “essential” in the sense that they contain the essence of the fragrance that is characteristic of the plant.  Essential does not mean indispensable or usable by the human body.  But despite that fact, essential oils have been used in folk medicine throughout history. 

In recent times, essential oils have frequently been used in aromatherapy.  Generally speaking, medicinal uses of essential oils are controversial, and, in some cases, they have even been demonstrated to be dangerous.

Research has shown that essential oils have potential as natural pesticides.  Recently, the USDA has funded research into the use of essential oils to battle pests and diseases of organic crops.

U.S. organic food sales topped $50 billion in 2018 and fruits, vegetables, and other specialty crops combined make up more than a third of organic sales.  In order to meet consumer demand, farmers need ways to battle pests and diseases that often accompany organic crop growth.

A four-year project at the University of Hawaii at Manoa is entitled “Plant Safety, Horticultural Benefits, and Disease Efficacy of Essential Oils for Use in Organically Grown Fruit Crops:  From the Farm to the Consumer.”   The researchers will work with certified organic producers in Hawaii, Florida, South Carolina, Georgia, and California to evaluate the effectiveness of plant essential oils on major fruit pathogens such as avocado scab, anthracnose fungal disease, and powdery mildew on targeted tropical and temperate fruit crops such as avocado, mango, blueberry, and peach.

The goal is increase orchard productivity of the expanding organic fruit industry.

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Essential oils could keep pests, disease from organic crops

Photo, posted January 6, 2015, courtesy of Abi Porter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bees Threatening Bees | Earth Wise

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Domesticated honeybees are an essential part of our agricultural system, being responsible for one in every three bites of food Americans consume and contributing $15 billion a year to the value of the nation’s crop production.  Millions of bee colonies are trucked across the country every year to pollinate cranberries, melons, broccoli, blueberries, and cherries, and also to produce honey.

After the growing seasons, honeybees are trucked to various locations to rest and rebuild their population and to replenish bees lost to disease and pesticides.  Some of these locations are in national forests.  Thousands of hives belonging to 112 apiaries are currently permitted in national forests by the Department of Agriculture.  This presents a problem because these hives are being permitted on public lands with virtually no environmental review and with little consideration of the impact these colonies can have on local wild bee populations.

The 4,000 wild bee species in the U.S. consume up to 95% of local available pollen.  Nearly 40 federally listed threatened or endangered species of bees, butterflies, and flower flies depend on national forest land for their survival.  And now the pollinators in these places, which were once refuges for these species and others, increasingly face competition from millions of domesticated honeybees.

Honeybees are super-foraging machines and are literally taking the pollen out of the mouths of other bees and pollinators.  Honeybees themselves have been facing numerous problems from habitat loss, pesticides, and other stress factors.  So, what is happening is essentially a pollinator habitat crunch that carries long-term implications for the U.S. food supply.  We need to find some answers and the sooner the better.

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Will Putting Honey Bees on Public Lands Threaten Native Bees?

Photo, posted August 9, 2015, courtesy of Tak H. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Crops May Need To Move | Earth Wise

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California has unique micro-climate diversity that creates ideal growing conditions for a wide range of crops.  One third of the vegetables and two-thirds of the fruits and nuts we eat in this country are grown on the more than 76,000 farms in California.  But as the climate continues to change, many farmers have started to worry about where and when crops can be grown in the future.   Within the next 20 years or so, some parts of California may become too hot and dry to sustain agricultural production.

According to new research from the Lawrence Berkeley National Laboratory, by the years 2045-2049, warmer temperatures will have a significant effect on cool-season crops such as broccoli and lettuce such that their growing season will need to shift.  On the other hand, warm-season crops like cantaloupe, tomatoes, and carrots will need to move to entirely new growing locations.

The study looked at five key crops that are produced more in California than elsewhere and studied the climate conditions under which they prosper and those under which they fail.  They established the range of conditions for which the crops can remain successful.  Finally they looked at climate projections for various parts of the state.

California’s agriculture is an essential part of our food security, so it is important to predict how future warming will affect when and where crops can be grown.  Changing these things presents challenges.  For example, when considering relocating crops, growers have specialized knowledge of their land and their crops.  If crops need to move to a new area, either the farmers have to move to that area, or they have to grow a different crop.  Either way, it presents a practical and economic burden on the farmer.

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Some of America’s Favorite Produce Crops May Need to Get a Move On by 2045

Photo, posted June 16, 2011, courtesy of the U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree-Planting Is Not Necessarily A Good Thing | Earth Wise

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There is no question that forests have a major role in efforts to combat climate change as well as to slow biodiversity loss.   As a result, tree-planting on a massive scale has gained traction as a strategy and there have been major commitments made to plant billions of trees around the world.

A new study at Stanford University has rigorously analyzed the potential effects of these efforts and has found some significant problems.  For example, the Bonn Challenge, which seeks to restore an area of forest more than eight times the size of California over the next 10 years, has 80% of its commitments in the form of  planting monoculture tree plantations or a limited mix of trees that produce fruit and rubber, rather than restoring natural forests.   The problem is that plantations have significantly less potential for carbon sequestration, habitat creation, and erosion control than natural forests.  The potential benefits of the planting dwindle further if planted trees replace natural flora – forests, grasslands, or savannahs – which are ecosystems that have evolved to support local biodiversity.

The study looked at previous policies that created subsidies for planting trees.  Chile’s Decree Law, in effect from 1974 to 2012, has served as a model for similar policies in a number of countries.  Those subsidies further reduced native forest cover by encouraging the establishment of plantations in places where forests might have naturally regenerated.  The subsidies expanded the area covered by trees, but decreased the area of native forests.

The study recommends that nations should design and enforce their forest subsidy policies to avoid undesirable ecological impacts and actually promote the recovery of carbon- and biodiversity-rich ecosystems.

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Poorly designed tree-planting campaigns could do more harm than good, according to Stanford researcher and others

Photo, posted April 28, 2016, courtesy of the U.S. Department of State via Flickr.

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Protecting Fresh Produce | Earth Wise

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Fresh fruits and vegetables can sometimes become contaminated by microorganisms during their long journey from fields to restaurants and grocery stores.  Contaminated produce can spoil other produce, which increases the number of fruits and vegetables in the supply chain that can cause illnesses. 

In order to prevent this cross-contamination between produce, researchers from Texas A&M University have designed a coating that can be applied to food-contact surfaces, like buckets, rollers, and conveyor belts.  The newly-created dual-function coating is both water-repellent and germicidal.  In other words, it can both repel and kill.  Without water, the researchers say bacteria can’t stick or multiply on surfaces, drastically reducing contamination.

To make this dual-function coating, the researchers chemically-attached a thin layer of silica to an aluminum sheet.  They then added a mixture of silica and lysozyme, a naturally-occurring germicidal protein found in egg whites and tears.  Together, the silica-aluminum and the silica-lysozyme formed microscopic bumps and crevices.  According to the research team, this rough texture, albeit microscopic, is the key to the coating’s superhydrophobic properties.  

The researchers tested the coating’s effectiveness at curbing the growth of two strains of disease-causing bacteria:  Salmonella and Listeria.  Upon review, the number of bacteria found on the dual-coating surfaces was 99.99% less than what was found on the uncoated surfaces. 

Despite the success in preventing bacterial spread, the research team said more research needs to be done to see how well the coating works for mitigating viral cross-contamination.  Since the coating would need to be reapplied after a certain amount of use, the researchers also plan to develop more permanent, dual-function coatings. 

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New dual-action coating keeps bacteria from cross-contaminating fresh produce

Photo, posted April 14, 2012, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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