Reading a recent Untapped New York post titled Central Park West, Over the Years, I was struck by the changes in the urban tree canopy on Broadway north of Columbus Circle between 1901 and 1912. (The 1912 photograph of Columbus Circle shown in the Untapped New York post was taken in the winter, I think, so street trees would hardly stand out without their leaves.)
I commented on Michelle Young's post asking if she knew the reason for the changes in the street tree canopy though a quick search of the Library of Congress and the web revealed that the IRT subway route was under construction during the time period of interest. Michelle responded with answers from two students in the Central Park West Studio at Columbia University.
I found this picture from 1907 showing that (at least some of) the trees on Broadway survived the IRT construction. It looks like the trees are on a central median and also a dedicated “tree lawn” between the road and sidewalk. I’m guessing that the eventual widening of the sidewalk and the elimination of the central median probably had something to do with the loss of trees on Broadway. (- Alex Wallach)
I’m assuming the trees were removed for the later stages of the subway construction. They used the “cut and cover” method, so anything above the subway tunnels would have been removed. (-Julian Ferraldo)The photograph Alex referred to was one I found in the Library of Congress Digital Archives. It was taken in 1907 and is shown below. Julian's assumption is supported by information in The New York Subway, Its Construction and Equipment, Interborough Rapid Transit, 1904 (2004).
View the changes yourself.
|Image: Rapid transit work at 59th St. & Central Park west, June 8th, 1901 (source)|
|Image: Supporting elevated railroad by extension girders -- 64th Street and Broadway (The New York Subway, page 45)|
The work was all done by open excavation, the so-called "cut and cover" system, but the conditions varied widely along different parts of the line, and different means were adopted to overcome local difficulties....The natural difficulties of the route [presence of rock near the surface or loam and sand] were increased by the network of sewers, water and gas mains, steam pipes, pneumatic tubes, electric conduits and their accessories, which filled the streets; and by the surface railways and their conduits....*
As the subway is close to the surface along a considerable part of its route, its construction involved the reconstruction of all the underground pipes and ducts in many places, as well as the removal of projecting vaults and buildings, and, in some cases, the underpinning of walls. (The New York Subway, pages 40-43)
|Image: Subdivision of 36" and 30" gas mains over roof of subway -- 66th Street and Broadway (The New York Subway, page 43)|
The method of undermining the tracks on Broadway from 60th to 104th Streets was entirely different, for the conditions were not the same. The street is a wide one with a 22-foot parkway in the center, an electric conduit railway on either side, and outside each track a wide roadway. The subway excavation extended about 10 feet outside each track, leaving between it and the curb ample room for vehicles. The construction problem, therefore, was to care for the car tracks with a minimum of interference with the excavation. (page 45)
|Image: Columbus Circle, New York, 1907 (source) -- view larger image here|
|Image: Columbus Circle, New York, 2011 (Microsoft BING Bird's Eye)|