September 2022

Master Gardener’s Trowel Talk Newsletter

On Line Learning, Gardening Events & Resources

Year of the Garden

Plant Science & Gardening News

• Biodiversity
• Chemicals
• Children
• Citizen Science
• Climate Change
• Conservation
• Crime
• Eye-Candy, Oddities and Miscellany
• Food & Agriculture
• Food Preservation & Storage
• Fungi
• Garden Reading
• Gardening
• Ig Nobel Awards
• Indigenous Plant Wisdom
• Invasive species
• Land Use & Planning
• Pests & Diseases
• Plant Fashion
• Plant Genetics & Breeding
• Plant Science
• Pollinators, Molluscs and Other Invertebrates
• Soil & Fertilizer
• Sustainable Living
• Trees & Forests
• Water
• Women in Science

Master Gardener’s Trowel Talk Newsletter

• The September edition of Trowel Talk opens with Andrea Knight’s article on a lovely fall native, the smooth aster. We answer your questions about funny coloured leaves on a maple, rejuvenating soil where tomatoes have grown for years. Lanark MG Dale Odorizzi explores the fascinating and complex life cycle of aphids. You may never look at these pesky critters the same way again! Claire McCaughey shares her tips for late season gardening. Mary Crawford continues her series on weeds with purslaine – another weed with super-food potential. Gail Labrosse continues her series on invasive plants with a look at that fall classic, burning bush or winged Euonymus. We end by publishing a letter from Trish Murphy, proprietor of native plant nursery Beaux Arbres, who suggests a couple of big, bold and beautiful native plants to add to the garden.
• As usual, we include links to our gardening and veggie growing calendars, and a list of places where you can find us. This year, Master Gardeners is returning to your local farmers’ markets to offer free gardening advice. Stop by and say “hello”.

• Trowel Talk is a collaboration between Master Gardeners of Ottawa-Carleton and Lanark County Master Gardeners, so you get both urban and rural perspectives.
• Trowel Talk Live! – Continues every Wednesday at 12:30 pm. Tune in for your weekly dose of gardening fun and advice, including a chance to ask your own questions.

On Line Learning, Gardening Events & Resources

Note: All event times are given as Eastern Time (US and Canada).

• Ecology Ottawa 2022 Tree Giveaways: Ecology Ottawa has 20,000 trees to give away, including 22 species of native coniferous and deciduous trees—including more fruit, nut, berry, and sap-bearing trees than ever to help address food security in the region. But this Tree Campaign is about more than putting trees in the ground. It’s also about engaging residents and public organizations to help nurture a greener community, a greener Ottawa, and a greener future together. Together, we can help Ottawa become healthier and more resilient! Check out the Tree Giveaway Calendar for more details. 
• Starting Monday, September 19:  Canadian Museum of Nature presents Winged Tapestries: Moths at Large. Moths explode in colour and size with the return of large-format photographs by Jim des Rivières. These extraordinary works, which débuted in 2010 and then toured to numerous venues, reveal the diversity and astonishing beauty of moths from the Ottawa region. Visitors will be struck by the detail, patterns and colours in 20 captivating photographs. Included with museum admission.
  Wednesday, September 21, 7:00 pm: Canadian Parks and Wilderness Society annual general meeting. Mark your calendars! More information will become available in the months to come.
• À partir du lundi, ie 19 septembre : Musée canadien de la nature present  Papillons de nuit : plus grands que nature. Les papillons de nuit de toutes les couleurs et dans toute leur splendeur nous reviennent avec les photographies de grand format de Jim des Rivières. Ces œuvres extraordinaires ont été présentés pour la première fois en 2010 avant de partir en tournée. Ils révèlent la diversité et l’extraordinaire beauté des papillons de nuit de la région d’Ottawa. Les couleurs et les motifs admirablement rendus par les photographies captivantes sauront ravir le visiteur.
• Tuesday, September 27, 7:30 pm: Ottawa Horticultural Society presents Urban Homesteading: Channelling our Pioneer Ancestors. OHS president Jeff Blackadar, together with Master Gardeners Judith Cox and Rebecca Last will describe their efforts to practice sustainable urban agriculture and living. Jeff will discuss gleaning on greenbelt land and tapping trees to make maple syrup. Judith will introduce us to her “turkey-turned” hügelkultur and “the girls” – chickens Peony, Dahlia and Calendula, who produce multi-coloured eggs. Rebecca will discuss the various ways she uses her small suburban garden to make food, crafts and gifts for friends and family. This event is available in person at St. Mark’s Church Hall, 1606 Fisher Ave, Ottawa, and on line.
• Wednesday, October 5, noon to 1:00 pm EDT: Webinar: Arborists Are from Mars; Garden Designers Are from Venus. Working around trees in a landscape is a delicate and careful business that is often overlooked, much to the detriment of the trees over time. It can be hard to spot what gardening practices cause trees harm, as it might be a decade before one unfortunate trench kills a tree. Chris Roddick will explore how Arborist and Garden Designers can work together when designing, developing, and managing gardens and lawns around trees. Registration required.
• Thursday, October 6, 6 pm: Carleton University and Canada Museum of Science and Technology present a Geodiversity Symposium: The Foundation for Diverse Ecosystems on a Changing Planet. The symposium is free and can be attended either in person or virtually. However, pre-registration is required.
• Tuesday, October 11, 7 pm: Old Ottawa South Garden Club presents “Selecting Trees for Your Property”. Starting with municipal programs and requirements related to trees, this presentation encourages people to look at their property’s environment, as well as their own needs and values in order to select trees to enhance their property for years to come. Meetings are held at the Old Ottawa South Community Centre (The Firehall), 260 Sunnyside Avenue. Membership: $25 per year; $40 for a family; drop-in fee—$7 per meeting. Information: Old Ottawa South Community Centre at 613 247 4946
• For more gardening events in the Ottawa area, including a useful selection of virtual events, consult the Gardening Calendar.

Year of the Garden

• 2022: Did you know? 2022 has officially been declared as The Year of the Garden.
• Canada’s Garden Route Map: The COVID-19 pandemic restricted travel opportunities for Canadians and also for visitors from around the globe. Canada’s Garden Route is not a ‘route’ per se, but a comprehensive listing of Canadian gardens and garden experiences that eagerly await visits from their surrounding communities and tourists from afar.

Thanks to Jon Last for this month’s humorous image. « Lorsque vous avez mis en conserve toutes les recettes possibles, que votre famille refuse de répondre à vos appels parce qu’elle sait que vous essayez de vous débarrasser de plus de courges et de courgettes… Voici les courges flamants roses ! Bientôt dans la cour de votre voisin ! »

Plant Science & Gardening News

Biodiversity

• Three decades of research culminates in more unique orchid species: Researchers have spent 30 years searching the rugged Kimberley region of Western Australia for orchids, with their work finally culminating in a paper published in Telopea. They used helicopters, 4WDs and quad bikes to traverse through remote territory, so far locating three tree orchids and 17 ground orchids. Australian Institute of Botanical Science researcher Dr. Russell Barrett said with the Kimberley having a strong seasonal climate, including a nine-month dry season, it was easy to think there was little habitat available for orchids. “Finding orchids in such a remote region can be a slow process, and this research has taken 30 years to reach publication,” he said. “Many people have assisted with the search over the decades, particularly Kimberley locals Robin and Butch Maher, both with a keen eye for potential habitats, and crucially, a helicopter at hand.
• Biodiversity certificates to increase native habitat and support Australian landholders: The Australian Labor Government has today announced the creation of a biodiversity certificates scheme. The scheme recognises landholders who restore or manage local habitat and grants them biodiversity certificates which can then be sold to other parties. This will operate in a similar way to our current carbon crediting legislation. The scheme will make it easier for businesses, organisations and individuals to invest in landscape restoration and management. As companies look to invest in carbon offsetting projects like tree planting, we need to make sure there is a path for farmers and the environment to benefit. We need to protect waterways, provide habitat for native species, reduce erosion, protect topsoil, improve drought resilience and create shelter for livestock. A biodiversity market will also promote management of existing, remnant vegetation that provides habitat for native species. As the recent State of the Environment report found, Australia’s environment is poor and deteriorating and government cannot foot the bill alone. The markets for biodiversity and carbon credits will operate in parallel, both regulated by the Clean Energy Regulator. Over coming months the government will be consulting widely on the detailed rules for scheme – for example the rules on how biodiversity benefits should be measured and verified.

Chemicals

• Study first to link weed killer Roundup to convulsions in animals: A recent report by the United States Centers for Disease Control and Prevention found more than 80 percent of urine samples from children and adults in the U.S. contained the herbicide glyphosate. A study by Florida Atlantic University and Nova Southeastern University takes this research one step further and is the first to link the use of the herbicide Roundup, a widely used weed killer, to convulsions in animals. Glyphosate, the weed killer component in Roundup, is the world’s most commonly used herbicide by volume and by land-area treated. Glyphosate-resistant crops account for almost 80 percent of transgenic crop cultivated land, which has resulted in an estimated 6.1 billion kilos of glyphosate sprayed across the world from 2005 to 2014. Roundup is used at both industrial and consumer levels, and its use is projected to dramatically increase over the coming years. A major question, yet to be fully understood, is the potential impact of glyphosate on the nervous system. “It is concerning how little we understand the impact of glyphosate on the nervous system,” said Akshay S. Naraine, MSc., project lead and a Ph.D. student at FAU and the International Max Planck Research School for Synapses and Circuits. “More evidence is mounting for how prevalent exposure to glyphosate is, so this work hopefully pushes other researchers to expand on these findings and solidify where our concerns should be.” Results, published in Scientific Reports, showed that glyphosate and Roundup increased seizure-like behavior in soil-dwelling roundworms and provides significant evidence that glyphosate targets GABA-A receptors. These communication points are essential for locomotion and are heavily involved in regulating sleep and mood in humans. What truly sets this research apart is that it was done at significantly less levels than recommended by the EPA and those used in past studies.

Children

• New evidence shows planting around school playgrounds protects children from air pollution: Scientists have published new evidence showing that selective planting of vegetation between roads and playgrounds can substantially cut toxic traffic-derived air pollution reaching school children. The new findings, published in the journal Scientific Reports, demonstrate that roadside vegetation can be designed, installed and maintained to achieve rapid, significant and cost-effective improvement of air quality. Exposure to traffic-related air pollution has been linked with a range of health risks including cardiovascular, respiratory and neurological health. These risks are likely to be exacerbated in young children attending primary schools next to busy roads as their major organs are still developing and children have a higher breathing rate than adults. Exposure to fine particulate matter in air pollution is reportedly the largest environmental risk factor contributing to cardiovascular deaths and disease globally, and is linked to around six to nine million premature deaths each year. A team of researchers led by Barbara Maher, Emeritus Professor at Lancaster University, and supported by Groundwork Greater Manchester, installed “tredges” (trees managed as a head-high hedge) at three Manchester primary schools during the summer school holidays of 2019. One school had an ivy screen installed, another had western red cedar and the third school had a mixture of western red cedar, Swedish birch and an inner juniper hedge. A fourth school, with no planting, was used as a control. The school with the ivy screen saw a substantial reduction in playground particulate matter concentrations, but an increase in black carbon. The playground with the mixture of planting saw lower reductions in air pollution to that of the western red cedar. The biggest overall reductions in particulate matter and black carbon were shown at the school with western red cedar planted. The results showed almost half (49%) of black carbon and around 46% and 26% of the fine particulates, PM2.5 and PM1 emitted by passing traffic were captured by the western red cedar tredges.

Citizen Science

• Boy’s discovery reveals highly complex plant-insect interaction: When eight-year-old Hugo Deans discovered a handful of BB-sized objects lying near an ant nest beneath a log in his backyard, he thought they were a type of seed. His father, Andrew Deans, professor of entomology at Penn State, however, knew immediately what they were—oak galls, or plant growths triggered by insects. What he didn’t realize right away was that the galls were part of an elaborate relationship among ants, wasps and oak trees, the discovery of which would turn a century of knowledge about plant-insect interactions on its head. M many plant-insect interactions are well documented. For example, most “cynipid” wasp species have long been known to induce oak trees to produce protective galls—or growths—around their larvae to ensure the safety of their developing offspring. Additionally, certain plants—including bloodroot (Sanguinaria canadensis), a wildflower native to North America—produce edible appendages, called elaiosomes, on their seeds to attract ants, which then disperse the seeds by carrying them back to their nests. This latter example is referred to as “myrmecochory”—or seed dispersal by ants. “In myrmecochory, ants get a little bit of nutrition when they eat the elaiosomes, and the plants get their seeds dispersed to an enemy-free space,” Deans explains. “The phenomenon was first documented over 100 years ago and is commonly taught to biology students as an example of a plant-insect interaction.” The team’s new research—initiated by Hugo’s discovery of galls lying near an ant nest—revealed a much more complex type of myrmecochory, one that combined the wasp-oak gall interaction with the edible appendage-ant interaction. “First, we observed that, while these galls normally contain a fleshy pale-pink ‘cap,’ the galls near the ant nest did not have these caps, suggesting that maybe they were eaten by the ants,” says Deans. “Ultimately, this led us to discover that gall wasps are manipulating oaks to produce galls, and then taking another step and manipulating ants to retrieve the galls to their nests, where the wasp larvae may be protected from gall predators or receive other benefits. This multi-layered interaction is mind blowing.” The team’s findings were published in the journal American Naturalist.

Climate Change

• US takes on farming emissions in climate bill: On Tuesday 16 August, US president Joe Biden signed a bill into law that he described as “the most significant legislation in history to tackle the climate crisis”. As Carbon Brief reported in an in-depth media summary, the Inflation Reduction Act contains $437bn of spending – mostly on climate and health measures – and was agreed after months of haggling with Democrat senator and coal-industry supporter Joe Manchin. The IRA devotes most of its climate spending to scaling up renewable power, including $177bn for “clean electricity”, according to an interactive breakdown of the bill in the New York Times. However, the bill also contains nearly $17bn in “funding for agricultural practices that improve soil carbon, reduce nitrogen losses and decrease emissions”, says the paper – with almost $5bn for forest protection and restoration, and $4.6bn for drought resilience. Overall, just over 5% of the IRA’s spending is earmarked for changing farming practices, according to Vox, which added that the US food system accounts for 11% of its total greenhouse gas emissions.
• 7 young people sued Ontario over its climate policy. This week, they made their case: Seven young people who brought a landmark lawsuit against the Ontario government, alleging its climate plan fails to protect them and future generations, were heard in Ontario Superior Court in Toronto this week; the first time a climate lawsuit aimed at changing government policy has had a full hearing in court. The plaintiffs, represented by the environmental law charity Ecojustice, brought the suit in 2019 after the Progressive Conservative government of Premier Doug Ford replaced the former Liberal government’s climate plan. It ended the province’s cap and trade program and brought in a new, weaker emissions target. The plaintiffs want the court to order the province to bring in a new plan. The specifics would be left up to the government, but the plaintiffs want it based on science and to be compatible with the aims of the Paris Agreement, which aims to limit global warming to well below 2°C. “At current levels, the entire world is going to blow through the remaining carbon budget in five to 10 years, maybe even less,” said Nader Hasan, lead lawyer for the plaintiffs. Ontario is using a grossly disproportionate share of that carbon budget.”

Conservation

• Home gardens are ‘living gene banks’ that sustain livelihoods in Central Asia: Research on home gardens has shown the critical roles these play in the livelihoods and sustenance of rural dwellers worldwide, but little scholarly attention has focused on home gardens in Central Asia, particularly in the English language literature. In a new paper published in PLOS ONE, researchers address this gap and show the rich diversity—both within and across species—of fruit and nut trees that Central Asian home gardeners maintain. Drawing on interviews with home garden managers, the authors also show the links between trees in these gardens and their wild relatives in nearby forests.  The researchers found the home gardens were established about on average 40 to 50 years before the data collection, that is, during the rule of the Soviet Union, with some older home gardens over 70 years old found in Uzbekistan and Kyrgyzstan, and some very young ones found in Kyrgyzstan. In Tajikistan, “these trees have been vital for people to survive during times of conflict, and these home gardens with trees and vegetables play an important role to support families, providing a lot of the food for the household, in addition to income,” explains Barbara Vinceti, a forest ecologist and the lead author of the study.  Marlène Elias, a Senior Scientist at the Alliance of Bioversity International and CIAT, says home gardens’ role in sustaining and protecting a rich diversity of tree species make them “living gene banks. We looked at home gardens situated close to forests and examined how genetic material moves between the forests and the home gardens,” Elias said, adding that this flow between the two is critical to maintain tree and varietal tree diversity in both home gardens and forests. Yet, despite this rich diversity, Vinceti cautions that foreign varieties have become more common in home gardens because they are increasingly lucrative. Apple and pear varieties in particular are increasingly threatened by an influx of foreign commercial varieties. “We saw a significant erosion of local tree varieties of key species as more varieties come from outside,” Vinceti said, adding that commercial exotics coming in from the U.S., Russia and Europe were starting to replace local diversity in home gardens.

Crime

• Vandals Attack Trees in Public Garden: I was horrified by the news. I’m a great fan of the Halifax Public Gardens, an extraordinary public park and garden that I visit every time I’m in Halifax, Nova Scotia, Canada’s east coast metropolis. And much of its charm come from the extraordinary trees that decorate it. Well, vandals broke into the Gardens on the night of July 25 and 26, 2022 and tried to kill 30 historic trees, ranging in age from 50 to 200 years old. The first report I heard was on CBC radio and it just mentioned “damage.” So I thought, “a few branches broken off, maybe some bark peeled off. Most trees can handle that. It won’t be that bad.” Then I heard the word “girdled” and my blood ran cold. Girdling, also called ring-barking, involves is the complete removal of a ring of bark all around the trunk. With the bark gone, no more carbohydrates will be able to flow down to reach the roots. The police presume that there was more than one person involved. Currently, four trees deemed unrecoverable have been removed. In other cases, there’s hope; enough bark left intact for the trees to survive. So, the authorities have only cleaned the wound and don’t plan to carry out any further interventions. But the majority will undergo bridge grafting later this summer. Whatever decisions are made, dealing with this disaster will cost the Halifax Regional Municipality hundreds of thousands of dollars. Already, security cameras have been installed throughout the park and there will be 24-hour tree monitoring. The park also intends to plant substitutes for certain doomed trees.
• ‘I question the logic’: City tells longtime homeowner to replace part of front garden with grass: Georgina King rebuilt her front garden as a retirement project, replacing grass with artfully arranged plants, bushes and stone walkways. That was 17 years ago and King, now 78, says she loves it. Earlier this year, King received a notice of bylaw violation from the city telling her to “reinstate the city boulevard to its original state.” That means replacing the chunk of her front garden that the city owns as a right of way with grass, says King’s granddaughter, Ashley Wilson. If King doesn’t comply, the city could re-sod it and charge her for the work. King says the notice of violation has caused her “much stress and sleeplessness” and her efforts to appeal the notice have gone unanswered by the city. “I question the logic of a bylaw that favours outdated grass lawns over environmentally friendly and water-conservative options,” she wrote in a letter to the city that she says has gone unanswered. [Editor’s note: in May 2022, the city Transportation Committee approved a motion that could facilitate sustainable community gardening in the City-owned portion of front yards. The motion supports a comprehensive review of by-laws that eventually could support the development of gardening and naturalization in the City-owned right-of-way by local residents and community groups. Your editor is part of a small committee of the Ottawa Horticultural Society that is working with city staff to establish guidelines for implementing the proposed bylaw change.]

Eye-Candy, Oddities and Miscellany

• Goats and sheep deploy their appetites to save Barcelona from wildfires: Swapping sirens for bells and equipped with voracious appetites, Barcelona’s newest firefighting recruits began delicately picking past hikers and cyclists in the city’s largest public park earlier this year. The four-legged brigade – made up of 290 sheep and goats – had just one task: to munch on as much vegetation as possible. Their arrival turned Barcelona into one of the latest places to embrace an age-old strategy that’s being revived as officials around the world face off against a rise in extreme wildfires. The idea is simple: wildfire-prone areas are handed over to grazing animals, who chomp and trample over dry vegetation that could otherwise accumulate as fuel for fires. Whether the animals are semi-wild or overseen by a shepherd who is usually compensated for their efforts, a job well done usually leaves behind a landscape dotted with open spaces that can act as firebreaks.
• Rare orchid flourishes in Charles Darwin’s gardens after two-year project: A rare orchid that reproduces by getting wasps drunk is thriving in the gardens of Charles Darwin’s house after a two-year restoration programme. The violet helleborine is entirely pollinated by wasps, which are usually not perceived to be the best pollinators. They’re regimented and meticulously clean themselves, scientists say, which makes the process of pollination a fairly futile prospect – there’s nothing for the pollen to cling to. But the violet helleborine produces an intoxicating nectar cocktail to draw the wasps, which then end up buzzing all over the place and incapable of cleaning themselves. The pollen ends up anywhere the wasp may take it. Down House in Kent was the home to Charles Darwin and his family; his most famous book, On the Origin of Species, was written in the study there. The head gardener Antony O’Rourke said: “The gardens at Down House were Darwin’s ‘outdoor laboratory’ and are a living monument to some of the most important discoveries in the history of mankind.” The aim is to make the gardens look as if he had just stepped away.
• Ancient frogs in mass grave died from too much sex, new research says: Frogs once lived alongside dinosaurs. About 45 million years ago, the North Sea covered half of Germany. It’s incredible to think these little creatures survived the dinosaurs’ extinction. But a lower level mass death did take place in what is now called the Geiseltal region in central Germany and the cause has long remained a mystery. Hundreds of frog fossils were found in a mass grave in Geiseltal’s 45-million-year-old swampy coastlands, and their reason for being there has confounded scientists for decades. But my team’s study found an explanation: they died from exhaustion while mating. We also found evidence the mating behavior of modern frogs and toads dates back at least 45 million years as mass grave frog fossils from other sites show similar features on the skeletons as the Geiseltal specimens.
• Benny Goodman quote: “I remember when my late wife, a passionate and enthusiastic gardener had been listening to me practice through an open window repeating endlessly certain passages of a piece for a concert. She said, “Don’t you ever get tired of going over and over and over the same phrase?” I said, “It’s funny you should ask me that. I have been watching you working in the boiling sun for hours on end, weeding, digging, planting, pruning, covered with dirt and I’ve been thinking the same about you!” So perhaps one thing is common to gardening and music: good results depend on the work one is willing to put into it, and in the work itself you find your true enjoyment.” [Editor’s note: Thanks to Chief Chef Chuck Currie, who also happens to be an accomplished musician, for sharing this quote.]
• Nugget the cow: Seaweed-munching bovine chews on solution to methane problem: With a nose painted dark walnut, Nugget’s body is the color of a lightly toasted marshmallow. Her hair is soft when brushed one way, coarse when brushed the other. Weighing a queen-size 1,200 pounds, she likes to retreat to the back of the barn after her afternoon feeding frenzy concludes. Nugget has a few piercings on her creamy oval ears, one being a bright yellow tag displaying her name and identification number: Bovine 145 at the University of New Hampshire’s Organic Dairy Research Farm. A second piercing is an electronic sensor that triggers a nearby machine to measure her burps. As an adult Jersey cow, Nugget’s belching releases methane into the atmosphere, a potent greenhouse gas and the second most common behind carbon dioxide. But it’s not necessarily the type of obnoxious, roaring discharge done by characters in cartoons. “It’s quiet,” Andre Brito, an associate professor of dairy cattle nutrition and management at the University of New Hampshire, said of the burps. “It’s very difficult to actually hear.” As she saunters with attitude to her feeding stall, her enormous udder swinging between her legs, Nugget peers back, enveloping her dripping nose with her tongue in one swoop. No, she’s not a fossil fuel power plant or a gas-powered tractor trailer, but this blameless animal is, in fact, contributing to the climate crisis. Each year, Nugget and her numerous cow pals—roughly half a million of them in New England—generate about the same climate impact as nearly 240,000 gas-powered passenger vehicles driven for one year. Nugget’s annual contribution to global warming is about 220 pounds of methane. It’s a significant carbon hoofprint when you look at the scale of the dairy and meat industries globally. Nugget’s farm is part of a handful of federally funded projects in New Hampshire, Vermont and Maine where researchers are exploring different seaweed species, particularly those local to the Northeast, and how they impact the amount of methane cows burp.
• San Diego Zoo penguin fitted with orthopedic footwear (Update): A member of the San Diego Zoo’s African penguin colony has been fitted with orthopedic footwear to help it deal with a degenerative foot condition. The 4-year-old penguin named Lucas has lesions on his feet due to a chronic condition known as bumblefoot, which covers a range of avian foot problems, the San Diego Wildlife Alliance said Monday in a press release. If left untreated, bumblefoot could lead to sepsis and death by infection. The zoo’s wildlife care specialists turned to an organization called Thera-Paw, which creates rehabilitative and assistive products for animals with special needs. Thera-Paw created custom shoes made of neoprene and rubber to prevent pressure sores from developing when Lucas stands and walks. The penguin’s problems began more than three years ago. African penguins have suffered a massive population decline and are listed as endangered by the International Union for Conservation of Nature.
• A bitter mystery: Scientists sequence world’s oldest plant genome from 6,000-year-old watermelon seeds: In a new paper published in the journal Molecular Biology and Evolution, scientists from the Royal Botanic Gardens, Kew and partners in the U.K., Germany and the U.S. have decoded the world’s oldest plant genome, using Neolithic-era watermelon seeds collected at an archaeological site in the Sahara Desert in Libya. The study combined aspects of archaeological groundwork with cutting-edge genomics research to shed new light on the domestication of the watermelon and how our ancestors consumed the popular fruit’s ancient relatives. Surprisingly, evidence suggests the Neolithic Libyans had a taste for the watermelon’s seeds—a local delicacy still consumed today—but avoided the fruit’s bitter-tasting flesh. It is estimated that more than 200 million tons of the domesticated watermelon (Citrullus lanatus) are produced globally every year, with the crop being among the top 10 most important in Central Asia. The red-fleshed fruit is generally accepted to have originated in Africa, where a close relative (C. lanatus subsp. cordophanus) was most likely first domesticated in the Nile Valley and what is modern-day North Sudan. But the discovery in the early 1990s of supposed watermelon seeds at the Neolithic site of Uan Muhuggiag in Libya continued to puzzle scientists. Dr. Susanne S. Renner at Washington University in St. Louis, who together with Dr. Guillaume Chomicki at Sheffield University, led the study, said, “Seed morphology, especially of ancient seeds, was simply insufficient to reliably identify which species those Neolithic settlers in Libya were using.” The scientists were able to solve the mystery when they analyzed the seeds’ genome and recovered long stretches across all chromosomes—possibly the oldest genome ever recorded in such detail from a plant whose age has been verified using radiocarbon dating analyses. They also sequenced the genomes of dozens of watermelon specimens in Kew’s Herbarium collections, some of which were first collected in the early 19th century.

Food & Agriculture

• Neolithic culinary traditions uncovered: A team of scientists, led by the University of Bristol, has uncovered intriguing new insights into the diet of people living in Neolithic Britain and found evidence that cereals, including wheat, were cooked in pots. Using chemical analysis of ancient, and incredibly well-preserved pottery found in the waters surrounding small artificial islands called crannogs in Scotland, the team were able to discern that cereals were cooked in pots and mixed with dairy products and occasionally meat, probably to create early forms of gruel and stew. They also discovered that the people visiting these crannogs used smaller pots to cook cereals with milk and larger pots for meat-based dishes. The findings are reported in the journal Nature Communications.
• Farming out: China’s overseas food security quest: Drought has plunged water levels in China to a once-in-decades low. Some Chinese cities, reliant on hydropower, are going without air conditioning as temperatures soar and residents walk on dry riverbeds. But the most catastrophic consequences could be in store for the country’s food supply. On Aug. 23, four government departments warned that the autumn harvest, which supplies 75% of China’s grain, is under “severe threat” due to the drought. “The rapid development of drought superimposed with high temperatures and heat damage has caused a severe threat to autumn crop production,” they said in a statement. The anticipated poor harvest is the latest in a series of food supply shocks that have buffeted global markets this year, following the war in Ukraine that caused global shortages of everything from sugar to cooking oil.
• U.S. fruit sellers look to Canada for berry production amid drought, rising costs: As climate change makes traditional growing areas like California more costly, producers are looking north. American berry giant Driscoll’s has partnered with Sébastien Dugré, co-owner of Massé Nursery in Saint-Paul-d’Abbotsford, Que., to test whether commercial production of blackberries and raspberries is viable in the province. Quebec’s colder climate can limit berry crops, so growing them on a larger scale is unusual for that part of Canada. Dugré started the trials last year, and was able to harvest almost 80 tonnes of fruit this year. “There’s definitely a learning curve. Last year was rough, this year is way better, we’ve got better fruit,” he said. Dugré is using dome-like tunnels to protect the plants from rain, while creating a microclimate that is warmer for the plants. It all helps him to start earlier in the spring and end later in the fall, extending the growing season. “There’s big companies interested in doing business in Canada … to me that’s a good opportunity,” said Dugré.
• Les vendeurs de fruits américains se tournent vers le Canada pour la production de baies dans un contexte de sécheresse et d’augmentation des coûts : Les vendeurs de fruits américains regardent vers le nord, vers le Canada, alors que de graves sécheresses et des pénuries d’eau continuent de faire des ravages sur les cultures en Californie, le plus grand État agricole. Le géant américain des petits fruits Driscoll’s s’est associé à Sébastien Dugré, copropriétaire de Massé Nursery à Saint-Paul-d’Abbotsford, au Québec, pour tester si la production commerciale de mûres et de framboises est viable dans la province. Le climat plus froid du Québec peut limiter les cultures de baies, alors les cultiver à plus grande échelle est inhabituel pour cette partie du Canada. Dugré a commencé les essais l’année dernière et a pu récolter près de 80 tonnes de fruits cette année. “Il y a certainement une courbe d’apprentissage. L’année dernière a été difficile, cette année est bien meilleure, nous avons de meilleurs fruits”, a-t-il déclaré. Dugré utilise des tunnels en forme de dôme pour protéger les plantes de la pluie, tout en créant un microclimat plus chaud pour les plantes. Tout cela l’aide à commencer plus tôt au printemps et à terminer plus tard à l’automne, prolongeant ainsi la saison de croissance.

Food Preservation & Storage

• Preserving tomatoes 3 ways: Garden blogger Jessica Damiano offers three ways to preserve tomatoes in this fun blog. Your editor has been blessed with an abundant harvest of tomatoes this year. My preservation strategies include:
  • Freezing – I wash, core and scrore. That is, I cut out the core of the tomato at the stem end, then score the skin from north to south and freeze in zip-lock baggies. When thawed, the scored skins come off neatly, leaving whole fruit that can be used in soups, stews or chutney recipes.
  • Dehydrating – rinse the fruit clean and slice into ½ centimeter thick slices around the equator of the fruit. Lay these on a lightly greased baking sheet and place in the oven at 135°F, or use a dehydrator. The result is sun-dried tomato slices that will keep without refrigeration for up to 8 months and make a great gift for friends and family. You can also further process the sun-dried fruit into a sun-dried tomato pesto.

Fungi

• Big balls of fungi are cropping up across Quebec, to foragers’ delight: Mélanie Greffard and her husband usually head out to a nearby forest or the Eastern Townships to forage for mushrooms. So the pair had quite the surprise when they stumbled upon a Calvatia gigantea — a giant puffball the size of two basketballs in their backyard near downtown Quebec City last week. It weighed in at nearly six kilograms. “At first, it’s almost kind of scary, like, ‘What is this thing?'” Greffard said, laughing. “We were really impressed with how big it was.” Giant puffballs are large mushrooms, edible when fresh, that grow on grassy areas, often on lawns or fields. They typically appear in August and September, but puffballs the size of Greffard’s are a rare find. Greffard, who grew up in the countryside, credits her mother with getting her interested in mushroom-picking as a child. She said this discovery was pure luck. “We’re right in the heart of Quebec City … and nature is all around us. It’s just right there, in our backyard,” she said. “It’s just really cool to see that.” Greffard found a puffball at the same spot last year, but it was in its “puffing stage,” which is when the fungus begins to change colour inside and starts producing spores and is no longer edible. So she was happy when she saw that this one was firm inside and “very nice and white,” a sign it’s still good to eat.

Garden Reading

• Planta Sapiens by Paco Calvo review – extraterrestrials in the garden: In Denis Villeneuve’s 2016 movie Arrival the US army asks an expert in linguistics to decipher the complex language of the seven-limbed aliens (“heptapods”) who have landed on Earth. It’s a memorable and indeed moving attempt to portray the immense challenges involved in bridging the gulf of mutual incomprehension between two completely different species. I thought of Arrival while reading Paco Calvo’s remarkable book, the result of “two decades of passionate exploration into a rich and alternate world that exists alongside our own” – the world of plants. The subject of his exploration is startlingly radical: the question of whether plants can be regarded as possessing intelligence. Calvo is a professor of the philosophy of science in the Minimal Intelligence Laboratory at the University of Murcia, Spain. Although he presents detailed scientific evidence to support his case, he also draws on philosophical arguments about the nature of consciousness. We humans have a tendency to believe that the world revolves around us, but Calvo writes that intelligence is “not quite as special as we like to think”. He argues that it’s time to accept that other organisms, even drastically different ones, may be capable of it. Darwin has clearly been a guiding presence in Calvo’s attempt to open up a new frontier in science. In the course of his book, Calvo describes many experiments that reveal plants’ remarkable range, including the way they communicate with others nearby using “chemical talk”, a language encoded in about 1,700 volatile organic compounds. He also shows how, like animals, they can be anaesthetised. In lectures, he places a Venus flytrap under a glass bell jar with a cotton pad soaked in anaesthetic. After an hour the plant no longer responds to touch by closing its traps. Tests show the plant’s electrical activity has stopped. It is effectively asleep, just as a cat would be. He also notes that the process of germination in seeds can be halted under anaesthetic. If plants can be put to sleep, does that imply they also have a waking state? Calvo thinks it does, for he argues that plants are not just “photosynthetic machines” and that it’s quite possible that they have an individual experience of the world: “They may be aware.”
• À la recherche de recommandations de lecteurs : Si vous avez lu récemment des livres de jardinage en français intéressants, utiles ou inspirants, faites-le moi savoir ! J’aurai besoin du titre, de l’éditeur et de quelques phrases pour décrire le livre et expliquer pourquoi vous pensez qu’il vaut la peine d’être lu.

Gardening

• England’s gardeners to be banned from using peat-based compost: Sales of peat for use on private gardens and allotments will be banned in England from 2024, the government has announced. Environmental campaigners have long called for stricter laws to restore peatlands. As well as carbon capture and storage, peatlands provide habitat to some of the UK’s most threatened wildlife, and also filter water and prevent flooding downstream. But a combination of draining them for agricultural use, burning to create the right habitat for game birds and harvesting for compost means just 13% are in a near-perfect state. In 2011, the government agreed that the horticultural industry should voluntarily bring about an end to the use of peat, but by 2021 it still accounted for 29.8% of commercially sold compost. A public consultation, which received 5,000 responses, found 95% of people supported the ban and the Department for Food, Environment and Rural Affairs (Defra) admitted the voluntary approach had not succeeded. Bagged peat sold by retailers accounts for 70% of the peat sold in the UK, according to Defra. At this stage, the ban will not apply to those working in the horticultural trade, and that a date for this would be decided after a discussion with industry bodies in September. The chair of Natural England, Tony Juniper, said: “This ban on the sale of peat-based compost and work to phase out use in other areas is an essential step toward protecting these valuable natural assets and allowing for the recovery of degraded areas.”
• Getting Those Fall Leaves Off Your Lawn: Larry Hodgson recalls days of yesteryear when we burned fall leaves. He suggests new tools for raking, and new approaches to dealing with our fall leaves. These are not a waste product, of course, but a valuable resource for gardeners.

• How to prepare your container garden for winter: Odessa Palmer Parker writes a useful advice piece in the Globe and Mail for those looking to prepare their container gardens for winter. She wisely consulted some experts and your editor was honoured to be one of these.

Health

• Herbal Skin Care from Garden Plants: The great Larry Hodgson shares some tips for skin care based on common garden plants. Chamomile, mint, sage, lavender, thyme, rosemary, calendula and basil all have medicinal properties you can put to work to help your skin. This is a fun project to investigate this fall as our gardens begin to go dormant.
• ‘I’m glowing’: scientists are unlocking secrets of why forests make us happy: How happy do you feel right now? The question is asked by an app on my phone, and I drag the slider to the space between “not much” and “somewhat”. I’m about to start a walk in the woods that is part of a nationwide research project to investigate how better to design the forests of the future. Volunteers are being sought to record their feelings before and after eight walks on a free app, Go Jauntly, which could reveal what kind of treescapes most benefit our wellbeing and mental health. My guide is Miles Richardson, professor of nature connectedness at the University of Derby, who hopes the data he gathers from the Treefest walks will discover how the age, size and shape of trees and woodlands benefit wellbeing. “With the government’s ambitious tree-planting targets, there’s going to be hundreds of new forests around the country,” said Richardson. “The whole project is about creating design tools so we can create the best treescape for 50 years’ time. Is the best way to do it with densely packed plantations of trees in regimented rows? Is that more beneficial to your wellbeing than a less linear approach? We don’t know.” Scores of peer-reviewed studies have identified the myriad benefits of wooded landscapes on everything from improved cardiovascular and immune system health to depression, which decreased with immersion in a forest alongside lower levels of anxiety, anger, confusion and fatigue. But it appears the type of forest may be important too: intriguingly, several studies suggest that more biodiversity has a bigger boost on people’s mental health, while the recording of brain activity in response to forest density found a more relaxed state and reduced tension and fatigue in forests with a lower density of trees (from 30% to 50%) – suggesting that densely packed conifer plantations aren’t so restorative. The article also details how future AI may connect us to nature, and how soundscapes also impact our mood.

Ig Nobel Awards

• The sex lives of constipated scorpions, cute ducklings with an innate sense of physics, and a life-size rubber moose may not appear to have much in common, but they all inspired the winners of this year’s Ig Nobels, the prize for comical scientific achievement. Held less than a month before the actual Nobel Prizes are announced, Thursday’s 32nd annual Ig Nobel prize ceremony was, for the third year in a row, a prerecorded affair webcast on the Annals of Improbable Research magazine’s website. The winners, honoured in 10 categories, included scientists who found that when people on a blind date are attracted to each other their heart rates synchronize, and researchers who looked at why legal documents can be so utterly baffling, even to lawyers themselves. Though the ceremony was prerecorded, it retained much of the fun of the live event usually held at Harvard University. As has been an Ig Nobel tradition, real Nobel laureates handed out the prizes, using a bit of video trickery: The Nobel laureates handed the prize off screen, while the winners reached out and brought a prize they had been sent and self-assembled into view.

Indigenous Plant Wisdom

• Fruit and nut tree program aims to promote food sovereignty in Wabanaki communities: A U.S.-based Indigenous non-profit is trying to help Wabanaki communities have access to sustainable foods by distributing fruit and nut trees. Nibezun is based in Passadumkeag, Maine, roughly 50 kilometres northeast of Bangor, and is offering up to 300 beach plum, elderberry or American hazelnut trees to interested community members. The Wabanaki Confederacy consists of the Mi’kmaq, Wolastoqey, Penobscot, Passamaquoddy and Abenaki nations. Kassidy Bernard is L’nu (Mi’kmaw for person of the land) from We’koqma’q First Nation, about 240 kilometres northeast of Halifax, and uses they/them pronouns. Bernard was thrilled to learn about the food security initiative because they want to implement a food sharing program in their community. “Having that, to rely on each other and to sustain ourselves for such a basic need, it’s such a big reassurance to me,” said Bernard. 

Invasive species

• Woman stripped Ontario river full of pesky invasive plant — by hand: Katie Church has yanked so many patches of the pesky invasive European water chestnut this summer, she has dreams about doing it. “I look at the chestnut in the water and [dream of] removing it and making sure everything is clear,” she laughs. Church has just finished leading a field team of five summer students hired by the non-profit Invasive Species Centre. The group was tasked with searching, finding and plucking the thick, rooted green invasive aquatic plant by hand along a 30-kilometre stretch of the Welland River, in Ontario’s Niagara Region. [Editor’s note: This article includes a 1:30 minute video explaining the term “invasive species”.]

Land Use & Planning

• Reintroducing bison to grasslands increases plant diversity, drought resilience, study finds: A Kansas State University-led study has found that reintroducing bison—a formerly dominant grazer—doubles plant diversity in a tallgrass prairie. The research involves more than 30 years of data collected at the Konza Prairie Biological Station and was recently published in the prestigious journal Proceedings of the National Academy of Science, or PNAS. The study found that plant communities also were resilient to the most extreme drought in four decades. These gains are now among the largest recorded increases in species richness because of grazing in grasslands globally, researchers said. “Bison were an integral part of North American grasslands before they were abruptly removed from over 99% of the Great Plains,” said Zak Ratajczak, assistant professor of biology and lead researcher. “This removal of bison occurred before quantitative records and therefore, the effects of their removal are largely unknown.”

Pests & Diseases

• Plant-nibbling insects may make it cloudier and cooler: Plants can release certain chemicals to shield themselves from high temperatures and potentially communicate with other plants. They also release these chemicals in response to stress, including when insects chomp on their leaves. Now, in a study published in the Journal of Geophysical Research: Atmospheres, scientists have found that insect-damaged plants could release enough of these molecules, called volatile organic compounds, to locally alter the atmosphere and radiative budget above a forest. Once panicking plants release the compounds into the air, the compounds can oxidize, transforming into organic aerosols. Like aerosols emitted from human activity, these aerosols can theoretically change how clouds form and how much sunlight clouds reflect. Now for the first time in a global atmospheric model, Holopainen et al. consider the potential influence insect-munched plants can have on aerosol concentrations and clouds. These results suggest that insects eating plants could lead to stronger cooling effects from clouds, as greater aerosol concentrations typically correlate with sending more solar radiation back into space. These localized impacts won’t happen in an instant, but still, climate models could incorporate aerosol emissions from areas with intense insect herbivory to best estimate potential impacts on local atmospheric processes, the authors say.
• Box Tree Moth: A Toronto Master Gardeners Garden Guide: Toronto is the epicentre of a North American infestation of the box tree moth, Cydalima perspectalis (Walker). The arrival of this invasive pest was officially announced by the Canadian Food Inspection Agency in November 2018. The moth crossed into the US at Niagara in the summer of 2021, so the US is still in the very early stages of responding to the infestation. This pest (originally thought to have come from Asia) has now reached plague proportions. They are attacking (and sometimes killing) our pretty and widely-grown evergreen boxwood plants, Buxus spp. An infested boxwood plant is disfigured by the box tree moth by the loss of leaves, by webbing spun by the larvae, as well as larval excrements. Larvae feed principally on leaves of the host but may also attack the bark. They seem to prefer boxwood plants that receive partial shade but can also be found in full sun gardens. This long-ish article includes many links to other helpful resources as well as tips on identifying box tree moths, and treating the damage they do. [Editor’s note: this primer was prepared by Desre Kramer, who in addition to being a member of Toronto Master Gardeners is also my wonderful sister-in-law.]

Plant Fashion

• I Hate Cucamelons: Maybe you call them cucamelons, mouse melons, Mexican miniature watermelons, Mexican sour cucumbers, Mexican sour gherkin or pepquinos. Or in Spanish, sanditas, meaning little watermelons. But there’s just one plant behind all those names: Melothria scabra, native from Mexico to Venezuela. [Editor’s note: One of the things I love about Larry Hodgson’s posts is his fearlessness is addressing the sacred cows of gardening! I don’t object too much to the taste of cucamelons. My beef with them is that, self-fertile or not, they seem to be affecting my cucumber crop. I don’t know if the cucamelons are crossing with the regular cukes, or just setting a bad example, but I haven’t had a decent-sized cucumber this year. They’re all tiny little things that barely justify their existence in my small garden.]

Plant Genetics & Breeding

• Plant molecular geneticists discover, and begin to crack, the epigenetic code: When plants sense environmental challenges such as drought or extended periods of extreme temperatures, they instinctively reprogram their genetic material to survive and even thrive. The chemical code that triggers those changes can be deciphered and then duplicated to breed more vigorous, productive and resilient crops. That’s the conclusion of a team of Penn State molecular plant geneticists that conducted the first-ever study of those reprogramming effects and discovered that “epigenetic reprogramming” code, which results in the expressing and over expressing of some genes and the silencing of others. Understanding and someday harnessing that reprogramming process, the researchers contend, will be critical to breeding crops that can tolerate weather extremes brought on by climate change. “Plants can enter these new states—either really vigorous growth or, let’s say, hunkering down to withstand stress,” said team leader Sally Mackenzie, professor of plant science in the College of Agricultural Sciences and professor of biology in the Eberly College of Science. “In other words, we don’t have to cross breed to make it happen. We don’t need to add new genes because the plants actually go into that state, when properly prompted, on their own.” In the study, recently published in Genome Biology, the researchers manipulated the MSH1 gene to trigger at least four distinct nongenetic states to impact plant stress response and growth vigor. Cross-comparing data from these four states, they identified particular gene targets of epigenetic change within the genome where they could locate and decode data relevant to plant-growth.
• Researchers identify gene that participates in leaf response to environmental conditions: Heterophylly, the plasticity of leaf form in response to environmental conditions, occurs in aquatic and amphibious plants where it modulates leaf form, gas exchange and photosynthesis, providing a good model for plant acclimation to environment. Although heterophylly was widely seen in nature, no transgenic studies have been performed yet and its molecular mechanism is largely unknown. Hygrophila difformis (Acanthaceae) has recently merged as a plant model for the study of heterophylly due to its typical phenotypic plasticity to various ecological factors, but the mechanisms had not been identified. In a study published in Plant Physiology, a research team led by Prof. Hou Hongwei from the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences provided genetic evidence on the molecular mechanism of heterophylly in Hygrophila difformis.
• Ferns finally get a genome, revealing a history of DNA hoarding and kleptomania: Ferns are notorious for containing massive amounts of DNA and an excessively large number of chromosomes. Defying all expectations, a fern no larger than a dinner plate currently holds the title for highest chromosome count, with a whopping 720 pairs crammed into each of its nuclei. This penchant of ferns for hoarding DNA has stumped scientists, and the intractable size of their genomes has made it difficult to sequence, assemble and interpret them. Now, two papers published in the journal Nature Plants are rewriting history with the first full-length genomes for homosporous ferns, a large group that contains 99% of all modern fern diversity. “Every genome tells a different story,” said co-author Doug Soltis, a distinguished professor with the Florida Museum of Natural History. “Ferns are the closest living relatives of all seed plants, and they produce chemical deterrents to herbivores that may be useful for agricultural research. Yet until now, they’ve remained the last major lineage of green life without a genome sequence.” Two teams of researchers separately unveiled the genome of Ceratopteris (Ceratopteris richardii) this Thursday and that of the flying spider monkey tree fern (Alsophila spinulosa) last month.

Plant Science

• How light and temperature work together to affect plant growth: Plants lengthen and bend to secure access to sunlight. Despite observing this phenomenon for centuries, scientists do not fully understand it. Now, Salk scientists have discovered that two plant factors—the protein PIF7 and the growth hormone auxin—are the triggers that accelerate growth when plants are shaded by canopy and exposed to warm temperatures at the same time. The findings, published in Nature Communications will help scientists predict how plants will respond to climate change—and increase crop productivity despite the yield-harming global temperature rise. “Right now, we grow crops in certain densities, but our findings indicate that we will need to lower these densities to optimize growth as our climate changes,” says senior author Professor Joanne Chory, director of Salk’s Plant Molecular and Cellular Biology Laboratory and Howard Hughes Medical Institute investigator. “Understanding the molecular basis of how plants respond to light and temperature will allow us to fine-tune crop density in a specific way that leads to the best yields.”

Pollinators, Molluscs and Other Invertebrates

• Museum collections indicate bees increasingly stressed by changes in climate over the past 100 years: Scientists from Imperial College London and the Natural History Museum today published two concurrent papers analyzing UK bumblebee populations. The first investigated the morphology (body shapes) of bee specimens dating back to 1900. Using digital images, the group first investigated the asymmetry in bumblebee wings as an indicator of stress. High asymmetry (very differently shaped right and left wings) indicates the bees experienced stress during development—an external factor that affected their normal growth. Studying four UK bumblebee species, the group found evidence for stress getting higher as the century progressed from its lowest point around 1925. Further analysis showed that each bee species displayed a consistently higher proxy of stress in the latter half of the century. By taking the climate conditions during the year of collection—namely annual mean temperature and annual rainfall—the team found that in hotter and wetter years bees showed higher wing asymmetry. The study is published in the Journal of Animal Ecology.  in a second parallel study the team successfully sequenced the genomes of over a hundred bumblebee museum specimens dating back more than 130 years. In a pioneering advance, ancient DNA methods typically used for studying wooly mammoths and ancient humans, were for the first time used on an insect population. Scientists from the Natural History Museum and the Earlham Institute quantified DNA preservation using just a single bee leg from each of the bees studied. From these developments, published in Methods in Ecology & Evolution, the researchers can now look to determine how the reported stress may lead to genetic diversity loss. In conjunction with providing a new reference genome, the team will now use this data to study how bee genomes have changed over time, gaining an understanding of how whole populations have adapted—or not—to changing environments.
• Replacing pesticides with ants to protect crops: A team of researchers affiliated with several institutions in Brazil, working with one colleague from Spain and another from the U.S., has found evidence that suggests ants can be used as a natural pesticide for a wide variety of crops. In their paper published in Proceedings of the Royal Society B: Biological Sciences, the group describes how they analyzed studies conducted by researchers across the world to learn more about the possible use of natural pest control options by farmers and what they learned by doing so. Because of concerns about pesticide use, researchers around the world have started looking into the possibility of using natural pesticides. One such natural approach has involved the use of ants—they leave the crops alone and instead feed on the insects that damage plants. Use of ants to control pests has a long history, citrus growers in China, for example, have been using ants to control pests in fruit trees for centuries. In this new effort, the researchers wondered what other researchers have found when looking into the use of ants as a natural pesticide. Fifty-two published research papers involved looking into the use of ants as a way to control pests, covering 17 different types of crops. In analyzing the papers, the researchers found that most of the studies had led to discoveries of ants providing a high level of pest control—and in some cases, the ants were even better at it than commercial pesticides. They also found that the ants did their best work when used with crops grown in partial shade, and were the least effective when used with crops that produce honeydew—in such plants, ants tended to farm the insects, such as aphids, in order to provide themselves with the sweet liquid. The researchers conclude by suggesting that the use of ants to control pests appears to be a sustainable and inexpensive way to control pests on both large and small farms.
• Bee Lawns: What’s all the buzz about?: A bee lawn is a way to benefit pollinators in our landscapes by providing additional floral resources, and often utilizes a mix of low-growing flowering plants in addition to turf species. Habitat loss is one of the major factors implicated in the global declines of native bee species. Providing resources utilized by these critical pollinators can assist in mitigating this. Research through University of Minnesota has found 50 species of bees utilizing the flowers in bee lawns. The purpose of bee lawns includes providing nutritious sources of nectar and pollen for pollinators, especially in urban environments, where these resources can often be scarce and difficult to find. Additional factors include recreational usability, and reducing inputs, e.g., irrigation, nutrients, weed control, and time spent mowing. Flowering plants suited for bee lawns have a variety of common characteristics including: low-growing and flowering heights, perennial life cycles, the ability to persist with turf species, and tolerance of mowing and foot traffic. The rest of this timely and useful article provides tips on appropriate species of turf grass, flowering plants, and many other resources for those who want to shift to a more ecologically-friendly style of lawn.

Soil & Fertilizer

• Farming and fertilizers: how ecological practices can make a difference: Agriculture involves a difficult balance between food production and environmental impact. For example, fertilizers can help to achieve good crop yields, but over-using them produces greenhouse gas emissions and pollution. Some of these impacts also threaten future agricultural production. Greenhouse gas emissions, for instance, contribute to climate change and increase the likelihood of extreme weather events. To sustain agriculture, then, it is necessary to minimize the use of inputs like fertilizers, and support crop growth in other ways. One approach is through increasing ecological functioning within farms. This means enhancing relationships between different on-farm organisms, including crops, livestock, microbes, and wild plants and animals. Using these relationships to support crop yields is called “ecological intensification”. Previous research has shown that ecological intensification can be effective. But studies have only been done over short timescales of just a few years, whereas the effects of agricultural practices often take longer to become clear. Variation in weather between years can obscure effects in the short term, and some ecological processes take several years to stabilize. In a recent study, my colleagues and I explored whether long-term studies also support ecological intensification. To answer this, we sought out 30 long-term experiments from around Europe and Africa. We used these experiments to look at whether ecological intensification could reduce the need for two inputs: nitrogen fertilizer and tillage. We found that ecological intensification can partly replace fertilizers to support crop yields, because both ecological intensification and fertilizers increase soil nutrients. So farmers could use ecological intensification to reduce fertilizer use while maintaining the same yields. Farmers who already used low or no fertilizer could increase their yields.

Sustainable Living

• Pigs and Avocados: This article is a chapter from Viktorie Hanišová’s book, Beton a hlína [in English: Concrete and Clay], a collection of interviews with individuals practicing eco-friendly and sustainable ways of living in urban environments. On the northwestern outskirts of Prague lies a district named Vinoř. Right here, on the site of the prehistoric Nad Obůrkami hillfort, one finds Pastvina, a community garden and animal sanctuary. It feels like being in the backwoods, although we are still within the cadastral boundary of the capital city: there are garden beds with familiar and less familiar crops, the smell of horses, the constant cluck-clucking of chickens and grunting of pigs. A tidy garden it is not. There are things strewn all over: garden tools, wooden boards, tires, and other clutter. Chicken droppings are scattered on the ground and there’s even manure. It’s here that, going on four years now, gardener Marco Stella has been cultivating the land. For this interview, we sit down in the open “atrium,” which serves as a communal space for the community gardeners. Marco offers me water from the local well. I cautiously ask if it’s potable, as I must admit the environment doesn’t inspire complete trust in me. Marco just makes a face: “Worst case scenario, you’ll get the runs.” The rest of this article is an interview between the author and Marco Stella, the head gardener and originator of this sustainable growing space. They discuss space use, water issues and the finances of the garden.

Trees & Forests

• Characteristics of older forests can buffer effects of climate change for some bird species: Old-growth forests and managed forests with old-growth characteristics can provide relief from climate change for some bird species, research by the Oregon State University College of Forestry suggests. The study led by former Oregon State doctoral student Hankyu Kim builds on earlier research led by co-author Matt Betts, a professor in the Department of Forest Ecosystems and Society, that showed that old forests with big trees and a diversity of tree sizes and species can offer refuge to some types of birds threatened by a warming climate. The latest findings bear important implications on conservation decisions regarding mature forests, the scientists say, and have even greater relevance because of the new Inflation Reduction Act, which calls for increased resources to map and protect the United States’ remaining old-growth forests. The research, published in Global Change Biology, looked at forest “microclimates.” Microclimates are local atmospheric conditions, in areas ranging from a few square meters to many square kilometers, that differ from those of the surrounding area.
• Environmental scientists explain why so many tree species going extinct is so bad for the planet: A team of environmental scientists has written a follow-up paper to their study published last year that warned that approximately one-third of tree species around the world are in danger of extinction. In this new paper, published in the journal Plants, People, Planet, the group explains why the loss of so many tree species is so devastating and why attempts should be made to reverse such extinctions. The biggest problem, they note, is that loss of tree diversity makes life difficult for the tree species that remain. Forests grow smaller and become more susceptible to pests. And smaller and weaker forests mean less carbon sequestration, which means more carbon in the atmosphere warming the planet. It also leaves less forest available for use as a resource. Trees are sources of wood and paper products and are the biggest provider of fruits. Forty-five other scientists from 20 countries are backing their report. It also has the backing of the Botanic Gardens Conservation International and the Global Tree Specialist Group of the International Union for Conservation of Nature’s species survival commission. The researchers note that in addition to the dangers to the planet posed by loss of tree diversity, such losses would also harm many people directly. There are billions of people around the world who rely on forests for their livelihood. Loss of tree diversity, they note, would also adversely impact wildlife that make forests their home.

Water

• Arctic lakes are vanishing in surprise climate finding: The Arctic is no stranger to loss. As the region warms nearly four times faster than the rest of the world, glaciers collapse, wildlife suffers and habitats continue to disappear at a record pace. Now, a new threat has become apparent: Arctic lakes are drying up, according to research published in the journal Nature Climate Change. The study, led by University of Florida Department of Biology postdoctoral researcher Elizabeth Webb, flashes a new warning light on the global climate dashboard. Webb’s research reveals that over the past 20 years, Arctic lakes have shrunk or dried completely across the pan-Arctic, a region spanning the northern parts of Canada, Russia, Greenland, Scandinavia and Alaska. The findings offer clues about why the mass drying is happening and how the loss can be slowed. The vanishing lakes act as cornerstones of the Arctic ecosystem. They provide a critical source of fresh water for local Indigenous communities and industries. Threatened and endangered species, including migratory birds and aquatic creatures, also rely on the lake habitats for survival. The lake decline comes as a surprise. Scientists had predicted that climate change would initially expand lakes across the tundra, due to land surface changes resulting from melting ground ice, with eventual drying in the mid-21st or 22nd century. Instead, it appears that thawing permafrost, the frozen soil that blankets the Arctic, may drain lakes and outweigh this expansion effect, says Webb. The team theorized that thawing permafrost may decrease lake area by creating drainage channels and increasing soil erosion into the lakes. “Our findings suggest that permafrost thaw is occurring even faster than we as a community had anticipated,” Webb said. “It also indicates that the region is likely on a trajectory toward more landscape-scale drainage in the future.” [Editor’s note: several other academic links are provided in the original article.]
• From the soil to the sky: Researchers quantify the amount of energy that plants use to lift water on a global scale: Every day, about one quadrillion gallons of water are silently pumped from the ground to the treetops. Earth’s plant life accomplishes this staggering feat using only sunlight. It takes energy to lift all this liquid, but just how much was an open question until this year. Researchers at UC Santa Barbara have now calculated the tremendous amount of power used by plants to move water through their xylem from the soil to their leaves. They found that on average, it was an additional 14% of the energy the plants harvested through photosynthesis. On a global scale, this is comparable to the production of all of humanity’s hydropower. Their study, published in the Journal of Geophysical Research: Biogeosciences, is the first to estimate how much energy goes into lifting water up to plant canopies, both for individual plants and worldwide. “It takes power to move water up through the xylem of the tree. It takes energy. We’re quantifying how much energy that is,” said first author Gregory Quetin, a postdoctoral researcher in the Department of Geography. This energy is in addition to what a plant produces via photosynthesis. “It’s energy that’s being harvested passively from the environment, just through the tree’s structure.” The team combined a global database of plant conductance with mathematical models of sap ascent to estimate how much power the world’s plant life devotes to pumping water. They found that the Earth’s forests consume around 9.4 petawatt-hours per year. That’s on par with global hydropower production, they quickly point out.

Women in Science

• Tappūtī-Bēlet-ekallim, The Oldest Perfumer on Record: If you Google who the first perfumer in history was, you will find Tappūtī-Bēlet-ekallim; most likely, her name will be shortened to Tapputi. Online sources cast her as a proto-girl-boss, a kind of corporate feminist before the conception of capitalism. However, today let’s dig past the hype to look at the source material and see Tappūtī-Bēlet-ekallim not as the patron saint of corporate perfumery, but as one of many Assyrian workers who helped develop the bedrock of olfactory culture. What we know of the first perfumer in the historical record comes from one tablet. The tablet, KAR 220, is a scholarly concordance on perfumery and was housed alongside other chemical texts in the ancient library of Aššur. It is written in Middle Assyrian and currently resides in the Vorderasiatisches Museum in Berlin. The scribe of KAR 220 conveniently dated his work. The tablet was made in the 5th year of the reign of King Tukultī-Ninurta I on the 20th of the month of Muhur-ilani. (May 1239 BCE). The text includes the line, “from the mouth of the muraqqītu Tappūtī-Bēlet-ekallim.” This line is the totality of the written record about her, but that one line says so much. This is the oldest named perfumer in the historical record thus far. She was a woman. We know this because her name and her title, muraqqītu, are both in feminine form. Her work was reserved for the elites of society within a tightly controlled palace economy. The tablet describes her perfume as, fit for the king. This language is important. From the perfumers’ guild of Mari, we know that only men usually made fragrances for the king. In Assyria, or at least under Tukultī-Ninurta I, women, too, made fragrances for the highest tier of society. Yet, she didn’t have the title of šangitû bit hilṣi (f. overseer of the perfumer’s workshop), so while her work was worthy of recording, she probably had a boss. It is unlikely she was at the top of the pecking order of the bit hilṣi; her title would reflect that. The rest of this fascinating article  includes a translation of the formula for the salve, more of the history of the tablet and speculates on Tapputi’s origins as an Assyrian native, or perhaps a foreign worker, either a willing immigrant or perhaps one captured in battle.

That’s all the gardening news for this month. Remember, if you have a gardening question, you can still ask a Master Gardener by email. Until next month, happy gardening to all!

Rebecca Last