Tree Canopy Op-Ed: Evidence and Concession
Marisol is drafting an op-ed for her school newspaper arguing that the city should expand tree planting in the Eastside neighborhood. Her notes include: Eastside has 12% tree canopy, compared with 31% citywide; summer afternoon surface temperatures on Eastside asphalt average 9°F higher than in neighborhoods with more canopy; a 2022 city pilot planted 400 trees along two blocks and measured a 4°F drop in afternoon surface temperature at 3 p.m.; a resident survey found 68% support and 22% concern about roots damaging sidewalks; and the city has $150,000 available, with each tree costing $250 including three years of maintenance. Marisol wants to recommend a specific number of trees and to acknowledge the sidewalk concern without weakening her main argument. She also wants to use the strongest quantitative evidence for her heat claim.
1. Which piece of evidence from the setup most directly supports Marisol's claim that expanding tree planting would reduce heat in Eastside? Explain why the other quantitative details are weaker for that specific claim.
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The strongest evidence is the 2022 pilot: planting 400 trees along two blocks was followed by a 4°F drop in afternoon surface temperature at 3 p.m. That directly links planting to a measured temperature change in a similar urban setting.
The 9°F difference shows that Eastside is hotter than leafier neighborhoods, but it does not show that planting trees causes cooling. The 12% versus 31% canopy figures are also correlational. The 68% support and 22% concern are about resident opinion, not heat. The $150,000 budget and $250 per tree establish feasibility, not cooling effect.
2. Marisol wants to recommend the largest number of trees the budget can fund while keeping a $15,000 reserve for sidewalk repair. How many trees can she recommend? Show your reasoning.
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Subtract the reserve from the available budget: $150,000 - $15,000 = $135,000. Then divide by the cost per tree: $135,000 / $250 = 540. Marisol can recommend 540 trees while keeping the $15,000 reserve. This is a feasibility calculation, so it should be presented separately from the heat evidence.
3. Revise the following sentence to acknowledge the sidewalk concern and maintain her argument: 'Tree planting is clearly the best solution, and residents who worry about sidewalks are ignoring the heat problem.' Your revision should be 1-2 sentences and use a concession.
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Although some residents reasonably worry about roots damaging sidewalks, the city can pair expanded planting with root barriers and a repair reserve, because the pilot showed a 4°F cooling benefit. This revision concedes the concern is legitimate, offers a practical response, and keeps the heat evidence as the reason to act.