Most of the trees on Owl Acres are elms, walnuts, boxelders, hackberries and cedars. We only have one oak. It’s a red oak that we planted along the driveway about fifteen years ago. It was a sapling then, battling with the rabbits for survival. Those little creatures of the night wanted to eat its tender bark during its first couple of winters. The local tree pros told us to wrap it to keep the critters away from it. That turned out to be a bad idea though., Wrapping it created a nice protected habitat for insects, fungi and other pests to thrive. These new pests were as likely to kill the tree as the rabbits were. We took off the wrapping and left the tree to fend for itself. The tree survived, and now stands guarding the driveway.
Its smooth, light gray bark is changing as it ages to a reddish-gray-brown with broad, rounded scaly ridges. Its leaves are the traditional oak-leaf shape. The oak is deciduous, so its leaves are supposed to turn red in the fall, but ours only turned brown. For some reason, its leaves don’t fall in the autumn but hang on the tree all winter, giving more voice to the wind as the dry leaves rattle in the chill breezes.
In their native habitats in the forests of North America, Red oaks will grow up to 160 feet tall, stretching toward that bit of sunlight that shines through the forest canopy. Our red oak is planted in a clear space where it doesn’t have to compete for sunlight. It won’t need to grow as tall as its forest brothers, and will probably grow a thicker, sturdier trunk instead.
Red oaks live from 300 to 500 years. That’s a long time, so they’re not in any hurry to mature into acorn-producers. Ours is only about 25 years old, so it’s still a toddler, barely old enough to consider feeding the birds. When it’s ready, it will flower in the spring, producing catkins that grow at the point where last year’s leaves attach to their twigs. These are spikes of tiny male flowers that fling pollen on the breeze. Female flowers will also emerge, at the point where this year’s new leaves attach to the twigs. It will take our red oak two years to produce a crop of mature acorns, and it may take up to 25 more years to reach full maturity and become a consistent acorn-producer.
For centuries, people have used acorns for food. The acorns are impossibly full of tannins, though, and have to be processed carefully before they’re edible. This includes grinding the acorns into a meal or flour and then leaching the tannins out by running water through the meal. The water picks up the tannins, and eventually the meal is fit to eat. It takes several days though.
The mice, deer, squirrels, rabbits and other wildlife that eat the acorns don’t seem to mind the tannins. Neither do the Turkeys, woodpeckers and other birds that crack them open and eat the nut inside the shell.
Indigenous Americans also used the bark of the red oak for medicine. They chewed it or made tea with it as an antiseptic, and to cure mouth and skin sores and dysentery. They also made a black dye from the bark.
Red oaks thrived in the northern hardwood forests of the United States and Canada and are thought to have co-evolved with the passenger pigeon. Before European settlement, it is estimated that between two billion and five billion passenger pigeons inhabited these forests during their nesting seasons. Known as a “city of pigeons,” a huge flock of them would descend on a section of a forest where nuts were plentiful to feast on acorns, beechnuts and, to a lesser extent, chestnuts. Huge flocks of birds weighing literally tons would land on the trees, breaking off branches, depositing vast amounts of droppings, and making a lot of noise. The broken branches would open the forest to spots of sunlight where sun-loving red oaks could grow, reaching for more sunlight up to 160 feet above the forest floor. The bird droppings would have enriched the soil, and the birds thrived on the vast number of nuts produced in mast years. Hunting and deliberate destruction of flocks coupled with reduced habitat as the forests were converted to cropland caused the total extinction of the passenger pigeon with the last bird dying in the Cincinnati Zoo on September 1, 1914.
Like other native trees, the red oak has its cadre of insects specialized to thrive on its leaves. Some of these include the caterpillars of several Hairstreak butterflies and skippers and the juveniles of duskwings and caterpillars of many moths, including the orange-striped oakworm, and the sheathed Quaker moth. In addition another dozen Iowa insects have oak in their name, speaking to their close association with the trees.
Oaks have their fungal pests, too. Oak wilt is caused by a fungus that can be transmitted from tree to tree by the insects that live on the trees. It can also spread through the mycorrhizal networks that connect tree roots and will kill an oak within a year. Another group of disease-causing factors including drought, invasion by the larvae of oak borer insects, fungi and late frosts is called oak decline. This, too will kill a tree over a few years.
Red oaks are common throughout eastern Canada and the United States. Their wood is everywhere. It’s used in furniture, for instance, where the texture of its grain is easy to identify by touch. It takes stains well, though so may be disguised as another wood species. The wood trim in my house on Owl Acres is oak, as are the doors and hardwood floors. The bed is stained to look like cherry, but feels like oak.
Oak wood is close-grained, heavy and hard. It is relatively easy to work, and makes lovely furniture and veneers as well as sturdy tool handles, fence posts and railroad ties.
Hopefully our oak will stand guard on the driveway for decades to come, hosting birds, squirrels, moths and other life before it’s turned into fence posts or firewood.
Photo by Author. Alt text: Small Red Oak stands in the front yard. Brown leaves still hang on the tree, even though it’s winter in Iowa. Karen and Dave walk down the driveway in the middle background, red house and blue sky in far background. Sunshine lights all on a cold day.