Monday, February 26, 2007

In praise of trees

Tree on Sanchez Street, at 14th Street, in San Francisco's Duboce Triangle neighborhood.
Trees are truly wonderful things. They create oxygen while sequestering carbon, alleviating global climate change. They provide habitat for wildlife, even in an urban environment. And they are beautiful, green enhancements to any streetscape.

Of course, traffic engineers are less fond of trees. Their motto is wider, flatter, faster. Trees impede traffic flow: shade and foliage impair the motorist's field of vision, so drivers slow down.

Trees are therefore a great traffic calming tool, demonstrated very well by this large specimen on Sanchez Street near my home in San Francisco. It sits squarely amidst a popular city bike route 47 between the Mission/Castro and Golden Gate Park, and slows traffic better than any speed hump or enforcement.

In addition to traffic calming, trees provide shady relief for bicyclists during warm days, a benefit unnoticed by motorists in climate-controlled vehicles. Bicyclists are therefore great enthusiasts for trees, for their traffic calming, cooling, and aesthetic benefits.

(I would be surprised if this particular tree lasts another decade. Its roots are causing great buckling in the street pavement, and it has the misfortune to be located close to a fire station, which doubtless wants a clearer path for its vehicles.

Image: Paul Dorn. Tree on Sanchez Street, at 14th Street, in San Francisco's Duboce Triangle neighborhood.
Visit: Paul Dorn's Bike Commuting Tips Site

1 comment:

Jym said...

=v= The important thing with trees like that is to have a replacement already growing, so that when the mature tree dies there's something other than a sapling to take its place.

That neighborhood was designed by Donald Appleyard, and right now I'd say the main threat to it is a succession of arborists removing the lower canopies of so many trees there. It's an epidemic in this city.

Happy Arbor Day!