The Urban Pantheist

Photos by urbpan. This row of stately northern red oaks lines a street running along Brighton and Brookline.

Urban species #277: Northern red oak Quercus rubra

Oak trees--there are more than 500 species of them--have long been symbolic of strength, wisdom, and longevity. In Europe or the northeast of North America, the oaks may be the biggest trees in the forest, and their wood has always been among the most valuable. Oaks can roughly be divided between "white" oaks, with rounded leaf-lobes, and "red" oaks, with pointed leaf-lobes. White oaks are stronger and more valued, but do not do as well in the city. Their roots need more room than the compressed soil, asphalt, and concrete landscape can give them. The red oaks, on the other hand, do fairly well, and a number of red oak species are popular street trees.

Northern red oaks grow quickly, and can grow to impressive dimensions. Some street trees reach to 70 feet tall or more, even with the weight of cars and sidewalks on their roots. They are exceptional shade trees, and their foliage changes from rich green to a range of golden brown, to rusty, to scarlet, in autumn. The fruit of all oak trees is the familiar acorn, a tempting lump of starchy food in an adamant package. A whole suite of rodents--the tree squirrels--has evolved to take advantage of them, and to some degree oak trees depend on squirrels to bury their acorns, to reproduce. Native Americans made use of acorns for food, but red oak acorns were not their first choice; white oak acorns are far less bitter, but still require several changes of water to remove the tannins that make them inedible to humans. Acorns provide winter food for animals as diverse as non-migratory Canada geese, wild turkeys, woodpeckers, deer, raccoons, and many others. Over 200 different species of organisms produce galls in which to inhabit oak trees, and countless others live in their bark, branches, and cavities.


A fallen northern red oak leaf next to an acorn, a gall, and a honey locust leaflet, on a sidewalk in Allston.

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