Two red oaks, side by side, reaching for the sky. 

In 1950 New Jersey Governor Alfred Driscoll signed a proclamation making the red oak the state tree.  These official state designations usually don’t mean anything to me—I don’t really care that the honeybee is the state insect; the bog turtle is the state reptile; or that the tomato, which is a fruit, is the state vegetable.  But I have always liked the idea that red oaks are the state tree.  I suppose that is because I am very fond of red oaks and I think that they have a lot of qualities that are fitting for that designation.  It was chosen for “its strength, dignity, structural beauty, and long life.”  All of those things are true.  The strength of red oak wood, along with its durability and beauty, make it valuable for furniture making. Dignity and structural beauty are subjective terms but I urge anyone who doubts that red oaks are dignified and beautiful to go into a Sourland forest and look at one—or to look again at the photo above.  Their straight trunk and great height give them dignity and awesome beauty.  Normally red oaks will grow to between ninety and one hundred feet tall and three or four feet in diameter, but if they are growing in ideal conditions they can reach up to one hundred and sixty feet tall and eight feet in diameter.  As for their “long life,” red oaks can live for four hundred years, not as long as white oaks but still an age to celebrate.


I can think of other reasons to celebrate red oaks as our state tree.  First, they are adaptable.  Red oaks prefer to grow on the north-facing slope of a forest with deep, rich soil—which is true for almost any tree—but they will grow under many different conditions.  They have even been used to reclaim former coal mine sites because they manage to grow in the highly acidic soils of those wasted places.  Another reason to honor red oaks is that they make an important contribution to forest ecology. More species of Lepidoptera live on oak trees than any other tree species.  That not only means that the larval stage of moths and caterpillars find oaks to be welcome hosts but that the birds that feast on these caterpillars also benefit from the presence of oaks in the forest.  Both nest building and cavity-nesting birds like red oaks because their dense canopy makes a good cover.


Red oaks also contribute to forest ecology by producing important food every fall. Turkey, white-tailed deer, blue jays, nuthatches, chipmunks, all species of squirrels, bears, red-bellied and red-headed woodpeckers, and even several species of ducks eat red oak acorns.  Deer go a step further—a step too far for many of us—because they have a fondness for eating the leaves, twigs, seedlings, and saplings of red oaks.  


Native Americans made flour from red oak acorns after they leached the tannin from them.  They used the tannin to preserve and soften animal skins, making them suitable for clothing. They used the bark to make a preparation that they used to treat bowel problems. 


Red oaks, as well as all of the tree species that produce nuts, have an interesting pattern in their annual production of acorns and nuts.  Every two to five years they have an especially large crop.  These years of abundance are referred to as “mast” years, after an Old English word that means nuts.  (The same word that we use for the pole that holds a sail on a sailboat, a mast, is also derived from an Old English word, but a different one.) The consequence of this irregular production of acorns is that every few years acorn and nut trees produce more acorns and nuts than the wildlife can consume.  That means that there will be acorns and nuts left as seeds to regenerate the forest.  If every year were a mast year the mast eaters would increase in population, but the years without abundance keep their population in check. 


All of the oaks in a region have a mast year at the same time and the region can be a few acres or hundreds of square miles.  It is unknown how this wonderful, and necessary, coordination occurs, but scientists are looking into the possibility that the oaks are talking to each other, either through an airborne chemical or through chemicals passed from tree to tree through their roots, which are all connected through mycorrhizal fungi.