The Urban Pantheist

Oak trees reflected in my car's back window.

A big bin full of debris picked up by the landscapers, including thousands of acorns, many of which are now little oak trees. I was contemplating it as an urban nature picture when my 3:00 alarm went off. The wild garlic aerial bulblets pic was much better.

Oak trees, Franklin Park.

On our way to pick Charlie up from the vet.( A little gory )

On this day in 365 Urban Species: Northwestern crow.

Photos by urbpan. Location: the Riverway, Boston
Urban species #317: Swamp white oak Quercus bicolor


Location: Lawrence Schoolyard, Brookline.
Urban species #318: Bur oak Quercus macrocarpa

I know of at least two monumental swamp white oaks in the city. One looms next to Sever Hall on Harvard Yard in Cambridge. The other is pictured here, a broad and spreading mature tree at the end of the Riverway, across from Landmark center. This tree is probably about mid way through its 300 year life span. Swamp white oaks are fairly tolerant of urban stresses, provided that their roots have room to spread and aren't under the compressed soil of the street. The trees are native to eastern North America, found in low-lying areas near water. They occasionally hybridize with bur oaks.

The bur oak is a "species of special concern" in Massachusetts. It probably was never very common here, being a plant of the central North American plain states. There are a number of bur oaks in Boston and Brookline in schoolyards and city parks, and it may be more numerous as a planted tree than as a wild tree. Bur oak is distinguished by its huge shaggy acorn, which isn't produced until the tree is nearly 40 years old. It's one of the best acorns to eat, less bitter than the red oaks' tannin-laden fruit. The bur oak's leaf is distinctive as well, with large rounded lobes and a deep sinus between lobes near the leaf stem and lobes at the leaf end.

( two more swamp white oak pictures )

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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