The Mighty Northern Red Oak Tree

I’ve been thinking about acorns lately during my walks up to our mailbox. What concerns me is the relatively small size of the acorn crop this year, which means that many forms of wildlife will either have to go hunting for different food or go hungry, which in turn often leads to smaller wild mammal litters or bird clutches the following year.

Quite a few Northern Red Oaks grow in our higher woods to the south, with the elevation reaching around 770 feet above sea level, roughly 190 feet above that of Lake Michigan. The somewhat drier conditions and warmer summer temperatures apparently favor the Red Oaks.

Roy measures up Door County’s largest Red Oak tree.

One of my all-time favorite reference books is American Wildlife & Plants, A Guide To Wildlife Food Habits, by Martin, Zim, and Nelson. According to these experienced biologists, “Acorns rate a position at, or very near, the top of the wildlife food list, not so much because they are a preferred food item but because they constitute a good and abundantly available staple – the staff of life for many wildlife species.”

Five-star users (at the top) include the White-tailed Deer and Wood Duck. The four-star list contains the Turkey, Blue Jay, Black Bear, Raccoon, and Gray Squirrel from this region while three-star users include White-breasted Nuthatch, Red-headed and Red-bellied Woodpeckers and Ruffed Grouse. Chipmunks and White-footed Mice consume many of the acorns as do some of the more unlikely songbirds such as Brown Thrasher and Rufous-sided Towhee.

We’ve noticed relatively few Gray Squirrels on the ground below our “squirrel-proof” feeders lately, very likely because they are searching for and burying as many of the acorns in our woods as they can possibly find. During a good acorn year we will notice dozens of foot-long oak twigs containing acorns littering our driveway, which the squirrels, in their impatience for the acorns to ripen and drop naturally, have chewed off the trees. The squirrels then drop the twigs to the ground before retrieving the acorns and burying them.

It wouldn’t take you very long to learn, just as did wildlife, the American Indians and early settlers, that acorns from White Oaks are far superior for eating than those obtained from Northern Red Oaks. Do you suppose that the meat of squirrels that ate White Oak acorns would be better tasting than squirrels that consumed largely Red Oak acorns?

Red Oak acorns are quite bitter tasting due to the high amount of tannin they contain. However, the tannin, being water soluble, can be quite readily leached out of these acorns. Euell Gibbons, in his book, Stalking the Wild Asparagus, refers to the acorn as “an ancient food of Man” and tells how to effectively remove tannin from Red Oak acorns and use them as food. Northern Door has very few native White Oaks which produce acorns every year. It requires two years for acorns of Red Oaks to develop. Compared to the leaves of Red Oaks, which generally are green on both sides and have pointed lobes with tiny spines at their tips, leaves of White Oaks are whitish on their undersides and have rounded lobes. There are relatively few White Oaks in Door County with Red Oaks predominating.

A pile of Red Oak acorns.

The tallest tree on our property, estimated to be about 170 years old, is a Northern Red Oak with a trunk circumference of around nine feet. We can pause at a crossroads roughly two miles to the east-northeast from our house, look across the wide picturesque Hibbard Creek valley, and see the broad, spreading, symmetrical crown of the oak outlined against the horizon, standing taller than all nearby trees. What a magnificent stately landmark whose leaves hopefully will soon be turning a rich deep maroon.

Quite a few years ago, when my dad’s doctor ordered him, due to a heart problem, to stop watching the Green Bay Packer games on TV, we spent many pleasurable Sunday afternoons scouring quite a few Kewaunee County woods searching for potential Wisconsin state record trees. The closest we came was an American Beech, which was only two or three inches in circumference smaller than the largest in the state.

We did discover a gigantic Red Oak stump in our friend Henry Baumgartner’s woods northwest of Kewaunee. The tree had been cut down in 1944 and sold to someone who needed to make some hardwood flooring. The two-foot-high stump displayed 166 annual rings indicating that the tree began growing some time in the mid 1770’s! Whereas that is indeed a very good age for a Red Oak, some of the 85 species of oaks indigenous to the U.S. are known to attain an age of 600 or more years.

Our Door County Record Tree project, carried on by our Friends of Toft Point, Inc. group, has been informed of a gigantic Red Oak in the city of Sturgeon Bay with a trunk measuring 215 inches in circumference, measured at four and one-half feet above the ground. Unfortunately much of the crown had to be removed through the years resulting in a very short but fairly wide-crowned tree. This is one of the largest Red Oak circumferences in the state. The record, with a circumference of 226 inches, is in Dane County. However, that tree has an imposing height of 85 feet.

Here is an easy way of estimating the age of your large Red Oak tree. Measure the circumference of the tree in inches at four and one-half feet above the ground and divide that figure by 3.14 to obtain the tree’s diameter in inches. Multiply that number by 5 to arrive at the approximate age of the tree. Using this method, the Sturgeon Bay Red Oak is around 340 years old and might have started growing in 1670. By the way, each species of tree has their individual factor for coming up with the age of the tree. Perhaps I can go into this in more detail in a future story.

David Everett in 1791 wrote the memorable lines, “Large streams from little fountains flow, Tall oaks from little acorns grow.” I think of the possibility of one of the acorns now on the ground in our front yard germinating next spring and, hopefully during the following years, developing into an imposing landmark of an oak, producing thousands of acorns, feeding many wild creatures and planting other oaks in our and neighboring woods.

I am reminded too of the poem our friend Jeanne Halama of Chicago wrote: “Who eats one acorn eats millions. He fells a forest with one swallow.”