Each year as the trees grow, the benefits the trees provide will grow. These trees will help provide the following benefits:
1. Create safer walking environments - By forming and framing visual walls and providing distinct edges to sidewalks so that motorists better distinguish between their environment and one shared with people. If a motorist were to significantly err in their urban driving task, street trees help deflect or fully stop the motorist from taking a human life
2. Rain, sun, heat and skin protection - For light or moderate rains, pedestrians find less need for rain protection. In cities with good tree coverage there is less need for chemical sun blocking agents. Temperature differentials fall 5 to 15 degrees and are felt when walking under tree canopied streets.
3. Reduced harm from tailpipe emissions - Automobile and truck exhaust is a major public health concern and contains significant pollutants, including carbon monoxide (CO), volatile organic compounds (VOC), nitrogen oxides (NOx), and particulate matter (PM). Tailpipe emissions are adding to asthma, ozone and other health impacts. Impacts are reduced significantly from proximity to trees.
4. Gas transformation efficiency - Trees in street proximity absorb 9 times more pollutants than more distant trees, converting harmful gasses back into oxygen and other useful and natural gasses.
5. Lower urban air temperatures - A properly shaded neighborhood, mostly from urban street trees, can reduce energy bills for a household from 15-35% lowering energy costs to homeowners and consumers by shading homes from setting sun.
6. Time in travel perception- Other research and observations confirm that motorists perceive the time it takes to get through treed versus non-treed environments has a significant differential. A treeless environment trip is perceived to be longer than one that is treed (Walter Kulash, P.E.; speech circa 1994, Glatting Jackson).
7. Reduced road rage incidents - Although this may at first seem a stretch, there is strong, compelling research that motorist road rage is less in green urban versus stark suburban areas. Trees and aesthetics, which are known to reduce blood pressure, may handle some of this calming effect.
8. Longer pavement life - Studies conducted in a variety of California environments show that the shade of urban street trees can add from 40- 60% more life to costly asphalt. This factor is based on reduced daily heating and cooling (expansion/ contraction) of asphalt. As peak oil pricing increases roadway overlays, this will become a significant cost reduction to maintaining a more affordable roadway system.
9. Increased security - Trees create more pleasant walking environments, bringing about increased walking, talking, pride, care of place, association and therefore actual ownership and surveillance of homes, blocks, neighborhoods plazas, businesses and other civic spaces.
10. Connection to nature and the human senses - Urban street trees provide a canopy, root structure and setting for important insect and bacterial life below the surface. They act as essential lofty environments for song birds, seeds, nuts, squirrels and other urban life. We will most likely never see any advertisement for a marketed urban product, including cars, to be featured without street trees making the ultimate dominant, bold visual statement about place.