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Leafy Greens
Dolores Davies Jamison | Crest Road

Photo Dolores Davies.

“The tree, which moves some to tears of joy,” said English poet William Blake, “is in the eyes of others only a green thing that stands in the way.” In Del Mar, these two radically different perspectives are familiar to most, and more often then not, the latter viewpoint usually relates to “a green thing” blocking someone’s ocean view.

But, in many cases, properly trimming or lacing out a mature tree is the reasonable alternative, and it’s also healthier for the resident and the neighborhood. Cutting down a mature and healthy tree because it is blocking someone’s view or because a homeowner wants a “new” tree, is often short-sighted and unwise, as eliminating the tree undermines air quality. Trees absorb massive amounts of carbon and other harmful gasses from the atmosphere. But, when trees are chopped down, the carbon dioxide (CO2) is released back into the atmosphere, and the cooling and health benefits vanish along with the trees.

Scientists estimate that a single mature tree can absorb 48 lbs. of carbon a year, providing enough clean air for four people. A special report by the IPCC (Intergovernmental Panel on Climate Change) recently stated that tree-planting could sequester around 1.1–1.6 GT (gigatons) of CO2 per year. Recent research from the Swiss university ETH Zürich has documented that worldwide tree planting could remove two-thirds of all carbon dioxide emissions that are driving global warming. While reforestation efforts are especially critical in tropical areas like the Amazon, what make tree planting so popular in slowing global warming is the quickness in which it can be implemented. And, anyone can contribute by planting a tree or two or joining a tree planting effort.

Given the recent summers of record-breaking heat, numerous American cities are expanding their urban forests not only to improve air quality, but also to combat the heat island effect that negatively impacts dense urban areas with many buildings and paved surfaces and little tree canopy. A recent study from Portland State University which mapped heat levels in urban areas across the country found that on a sweltering summer day, temperatures can vary as much as 20 degrees in different parts of a city. The hottest temperatures were recorded in dense residential neighborhoods with plenty of asphalt but scant tree cover. The most leafy neighborhoods and homes adjacent to parks and other green spaces stayed cool with recorded temperatures an average of 16 degrees cooler.



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