How to plant a city tree, and where timber beats steel for buildings
The 鈥淪tockholm tree pit鈥� nurtures urban forests
Using more breathable materials reduces the need for irrigation and increases tree survival.
The design, pioneered in Sweden, involves giving a tree an underground structure of soil, stone, and biochar to aerate and fertilize. These layers allow trees surrounded by concrete to absorb more oxygen and rainwater. While the pits can be costly, Stockholm found that growth for these trees outpaced that of trees without the special pits, and they handle more storm runoff.
Why We Wrote This
In our progress roundup, better use of common materials generates environmental benefits. In Sweden, smart techniques keep urban trees alive. In Zambia, using local construction supplies sustainably supports the local economy.
鈥淲e found that the more breathable the materials we used, the happier the trees were,鈥� said Bj枚rn Embr茅n, Stockholm鈥檚 first 鈥渢ree officer.鈥� The technique he developed two decades ago has been adopted in parts of Hungary, Spain, and the United Kingdom.
Citing a growing body of research on the positive return on investment, the United Nations Economic Commission for Europe notes that urban forests can help 鈥渇uture-proof鈥� cities against growing populations and climate impacts.
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Clean energy outpaced fossil fuels in the U.S. for the first time
In March, solar, wind, hydropower, other renewables, and nuclear power met 50.8% of demand in the United States, according to think tank Ember.
Coal and fossil gas made up the remaining 49.2% of power generated. It鈥檚 a striking difference from a decade ago, when fossil fuels made up two-thirds of the energy resource mix. Clean energy tends to perform well in the windier and milder weather from March to May. Similar trends are observed from September to November.
Despite shifts away from federal support of clean energy, renewables are on the rise. In March 2025, solar and wind generation jumped by 37% and 12%, respectively, compared with the previous year. And fossil fuel generation fell by 2.5%.
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Building homes with local materials benefits the local economy and reduces environmental impacts
Working in Zambia, environmental architect Jeremy Gibberd found that conventional homes use imported materials such as aluminum and steel roofing. But up to 90% of capital costs could be spent on locally made materials, including compressed earth blocks, concrete tiles, and timber from sustainably managed forests. This spending can build homegrown enterprises that create jobs and result in greater economic diversity, with businesses more able to weather downturns.
Using local materials can lead to cheaper maintenance costs and lower carbon emissions from less long-distance shipping. Builders can also design structures better suited for traditional skills and the local climate.
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Modern and contemporary Indian artists are gaining recognition
South Asian artists have struggled to achieve the repute equal to Western peers鈥�, with few works making it to galleries and international fairs. But last year, Indian artists saw the largest surge in demand of any nationality, according to art broker Artsy. And in March, a work by M.F. Husain that was sold at auction set a record for modern Indian art at $13.8 million.
As Indians have gained more wealth, collectors in India and the diaspora have sought to invest in and see their culture represented at galleries and museums. In 2023, a new Museum of Art and Photography opened in Bengaluru. Major institutions such as the Metropolitan Museum of Art have hosted exhibitions of Indian art in the last year.
The community says better infrastructure is needed, with more government support, trained professionals, and affiliated companies such as logistics firms. Still, the boom has 鈥渞eally affirmed my hypothesis that as soon as these artists are given an opportunity to show in the west, they will immediately find an audience,鈥� said gallerist Rajiv Menon.
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Thailand bans the corporal punishment of children
The Southeast Asian nation became the 68th country to prohibit the use of physical or psychological violence in any setting. The disciplinary practice has been widely tolerated: In 2022, about 54% of Thais under age 14 received some form of physical or psychological punishment at home, according to the National Statistical Office.
UNICEF noted that the change aligns with the United Nations Convention on the Rights of the Child and recommended the government follow up with educational campaigns directed at families to promote positive disciplinary practices.
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