The scientific name of the Northern Red Oak, Quercus rubra, contains the latin term rubra which translates to red and alludes to the reddish interior of the tree’s heartwood, and the red Autumn foliage color.

If you have ever walked from Lincoln Avenue along North Balph Avenue to climb the steep hillside of Bayne Park to arrive at the entry porch of Bayne Library, you have likely paused breathlessly for a moment beneath this towering tree.  Your efforts may have occasionally been impeded by the waxy leaves it drops and its large round acorns that litter the ground, known as nature’s marbles, slipping beneath your feet.

Northern Red Oaks are known for being fast growing and one of the largest of the Oaks. Standing before a tree with a trunk so wide and a crown reaching so high may cause us to ponder the age of this magnificent specimen.  We would never cut this tree down or take an invasive trunk boring just to count its growth rings, but we can use a mathematical formula to calculate the approximate of the age of this tree.

Every tree type has a different growth factor.  The growth factor of the Northern Red Oak = 4.0. We decided to do the math on paper, but if you prefer to simply input the circumference in inches and select a tree name, the results are only a button click away using the online Tree Age Calculator. We measured its trunk circumference at breast height (CBH) at 4′-6″ above the ground, and even managed to break a tape measure in the process.  It measured 195″ in circumference, so its diameter is 62″.  The diameter in inches x growth factor equals approximate age of tree in years.

62″ x 4.0 = approximately 248 years old, but we must consider that the growth factors are based on forest trees. If the tree is a landscape specimen it may be younger than indicated.  It is fair to say that the tree is likely older than 200 years old.  This means it was already a large mature tree when Amanda’s home, currently known as Bayne Library, was built in 1875.  It is amazing to envision all the trees surrounding her home.  Local historian John Schalcosky recently posted a map of Northeast Bellevue from 1902 online that shows Amanda’s property full of trees.  Can you spot it on the map?   

Look in the enlarged image below for the building on the corner of an intersection completely surrounded by trees in the center of the image below directly above the second letter ‘L’ in LINCOLN AVE.

The branches and canopy of the Northern Red Oak typically begin high up on the tree.  This can make it difficult to observe as the leaves and branches as they are out of reach, so binoculars can be useful in revealing details that we otherwise wouldn’t be able to see.

The bark is of various shades of grey, with irregular furrows and a rough texture.  The disjointed narrow ridges rising between the furrows are often scaly and look similar to loosely intersecting ski tracks. The bark ridges of older Northern Red Oaks become even rougher and uneven especially at the base of the trunk.  When the tree is younger the ridges on the upper trunk can appear lustrous and smooth.

What a special delight to spot Northern Red Oaks in the springtime just as the buds are bursting and the small beautifully pink leaves blanketed in translucent down begin to emerge from the tree’s buds. As the leaves grow they tend to hang vertically on their stalks. They become a bright lime green in spring, turning a glossy dark green in summer, and finally becoming crimson red to gold in the Autumn. Each leaf is has deep lobes, with leaf tips forming bristly points.   

Male and female flowers are borne separately on the same branch.​ Male flowers occur in long yellow-green cylindrical hanging clusters called catkins shown above.

Small female flowers emerge from leaf axils with the appearance of tiny pink spikes. Looking closely along the new growth where the leaf stems originate, you can see the female flowers in the image above and below.

The female flowers are fertilized when wind transports pollen from male catkins. ​Afterwards the catkins simply fall to the ground.​ The female flowers will eventually become acorns, but they require two full growing seasons to become full-sized and ripen. If you look closely in the foreground of image above you can see an acorn that started to form during the previous year.

Once fully developed, the brown acorns are barrel-shaped with a scaly cap that is thin, flat, and shallow.

Acorns are of great benefit as a food source to many species of birds and mammals, including Chipmunks, Squirrels, Raccoons, Mice, Blue Jays, and Red-Bellied Woodpeckers.

A variety of birds construct their nests in the sturdy branches of the Northern Red Oak, while Squirrels, Bats, and Woodpeckers may create dens or nests in its cavities.

Oaks are known to support hundreds of butterfly and moth species including their caterpillars. Poised and completly still, this caterpillar found on a Northern Red Oak leaf uses mimicry to evade their predators. The caterpillar can remain safe when a predator thinks it is just a twig. This twig mimic caterpillar is from the family Geometridae, which means “earth-measurer” in Greek, and refers to their inching movements.

Observing Northern Rad Oak leaves can lead to fascinating discoveries like this round gall which occurs on the leaves when a female wasp lays an egg or eggs via her long ovipositor into the plant tissue which stimulates the abnormal growth. Cutting the gall open reveals its internal structure of white fibers radiating from the central larval capsule. The gall provides a protective place for the wasp larva to eat and grow until the proper time comes for it to leave the gall and emerge into the world.

Northern Red Oaks provide important hard strong wood for railroad ties, lumber, barrels, furniture, flooring, millwork, and veneer. 

Book Recommendations:

The Long, Long Life of Trees by Fiona J. Stafford is a beautifully illustrated book containing intimate and detailed explorations of seventeen common trees including Oak.

​The nonfiction book Nordic Knitting Traditions Knit 25 Scandinavian, Icelandic and Fair Isle Accessories by Susan Anderson-Freed includes an Oak related project – Katy’s acorn socks! Full-color charts make these fun designs easy to knit.

In the book Hug a Tree, Geronimo, Geronimo purchases his aunt’s farm and he discovers that the huge Oak tree on the property holds legendary secrets he must unlock!

Learn more about all the Trees of Bayne Park and explore our Interactive Bayne Park Tree Map to see the locations, photographs, and names of over a dozen different species of trees. Be sure to also visit our Treesources page to lean about local trees, caring for trees, and more.

Written by Linda, Spring 2020