American oak trees: an introduction to Quercus from America

The American Oaks – an introduction to Quercus native to America. Also see Trees & ShrubsOak trees / QuercusOak pdf To shop for Quercus for your garden visit the UK’s largest gardening website.


The fifty kinds of oak trees that are native to America are about evenly divided on the two sides of the Rocky Mountains. No Western oaks are found in the Eastern states, and none of our Eastern kinds grows wild on the other side of the mountains. The backbone of the continent is a bar that neither group has been able to pass.

To know fifty different kinds of oaks by sight, so as to call each one by its right name, is not an easy task; and yet it is not so difficult as it at first might seem. To begin with, any tree we meet, which bears acorns, we at once recognise as an oak. By this one sign, we are able to set this great family apart from every other tree. As soon as they are old enough, all oaks bear acorns. If a tree which we suspect to be an oak has no acorn to show us, on or under the tree, a little close looking will usually find some acorn cups still hanging on, or lying where they fell upon the ground.

The leaves of oaks are distinctive. In general, they are all simple, and their outline is oval. The borders are variously cut by deep or shallow bays, between sharp points or rounding finger-like lobes. They are leathery in texture, compared with leaves of most trees. After a little practice, we learn to recognise oak leaves, no matter how variously cut their borders may be.

In spring the flowers of oaks come out with the leaves. A fringe of catkins at the base of the new shoot is composed of pollen-bearing flowers. In the angles of the new leaves farther up the stem, we shall find the little acorn flowers, usually in twos. This is the flower arrangement of all the oaks; staminate and pistillate flowers on the new shoots, separate and very different from each other, but always close together, and always both kinds on each tree. The fringe of catkins falls as soon as the pollen is shed. Little, red, forked tongues are thrust out by the pistillate flowers to catch the golden dust when it is flying through the air, and thus to set seed. All through the summer, the little acorns are growing. We can find them in their tiny cups in the angles of the leaves.
In the autumn the acorns are ripe, and falling. Some trees will show acorns of two sizes, half-grown ones on the new shoots, and full-sized ones on the bare twigs, just back of the new shoots.

This peculiarity divides the oak family into two great groups. One group is composed of trees which have light-coloured bark, bear a crop every year, and in winter are bare of fruit. This is known as the White Oak Group. Its leaves have rounded margin lobes which do not end in sharp points, as many of the lobes of oak leaves do.

All of the oaks whose leaves have pointed, spiny lobes on their margin belong to the Black Oak Group. The bark of these trees is usually dark-coloured. The acorns require two years of growth. For this reason, there are half-grown acorns on the tree all winter, waiting for the second summer to bring them to maturity. Every autumn the acorns which are ripe are found on the twigs just back of the leafy shoots, which grew during the past summer. These acorns have completed their second year of growth.
When we hear any one speak of annual-fruited and biennial-fruited oaks, we know that the White Oak and Black Oak Groups are meant. If you see an oak tree whose leaves are cut into sharp pointed lobes, you will find acorns of two sizes on its twigs. If you look across the fence and see a pale-barked oak with finger-lobed leaves, and not a spiny point on their margins, you will know that acorns of but one size will be found. Fix these three points in mind. Then study all the oak trees you can find.

Trees of the White Oak Group have:
1. Rounded lobes on their leaf margins.
2. Acorns ripe in a single season.
3. Pale-coloured bark.

Trees of the Black Oak Group have:
1. Spiny-pointed lobes on their leaves.
2. Acorns requiring two seasons to ripen.
3. Dark-coloured bark

Those who know trees best agree that there is no nobler broad-leaved tree in the American forests than the White Oak. Tree lovers in England have but one native oak upon which to spend their loyal devotion, the tree worship inherited from Druid ancestors, whose temples were their sacred groves of oaks. The same feeling is in our blood, and roused at sight of an aged white oak, with stout, buttressed trunk, and great horizontal limbs supporting a rounded dome, much broader than high.

The tree is grey in winter. It stands bare of leaves, clothed in its pale, scaly bark. This is the time to study the framework of the dome. The limbs are twisted and gnarled, and their branches end in dense thickets of twigs. Each twig bears the winter buds, and five buds are clustered at the tip of each.

In spring these buds open, and a leafy shoot comes out of each. At the base are the yellow, fringed catkins of the sterile flowers, and above them, in the angles between leaves and twig, the fertile flowers thrust out forked tongues for pollen. These will be acorns next autumn, if the pollen falls upon them, and thus sets seed.

All summer the leaves are green, with pale linings, and when summer ends, they turn to rich shades of purplish red. The sweet acorns are ripe, and as they fall, thrifty squirrels are all about, gathering them into their hidden store-houses for winter use. Plenty of the thin, shallow cups we shall find, but the kernels are scarce, unless we come when they are falling in October.

The Indians taught the early colonists in America to use acorns of this species for food. They boiled them, like hominy, and found them not only nourishing, but good to eat.
If you find solitary white oaks growing here and there in a mixed woods, you may wonder how they were planted thus. The tree cannot scatter its own seeds. It depends upon the work of scampering nut-gatherers, in fur coats, that put away more acorns than they can eat during the long winter. An acorn that is left over in one of the dark pockets along a squirrel’s run-way sprouts in the spring, and in a few years it is a sturdy oak sapling. All oaks are dependent on outside help in planting.

White oak lumber is very high-priced. The wood of this tree we rarely see nowadays except in the most expensive oak furniture. The beautiful satiny streaks that are the chief ornament of the grain in polished table tops, are bands of fibres that radiate from the central pith to the bark. When oak is “quarter-sawed,” these pith rays, called “mirrors,” show to best advantage. They are most numerous in the wood of the white oak.

The largest acorn I know is the fruit of the bur oak, and it is borne in a mossy cup, indeed. The cup’s scales are drawn out into long, hairy points, and those near the rim form a loose fringe. Once in a while you may find an acorn almost covered up in its husk. But as a rule, the nut is a little more than half-covered. Sometimes these nuts are two inches long, but this is not usual. They are over an inch long, and almost as broad, and the meat is white and sweet. No wonder squirrels harvest the crop, and young trees spring up wherever an acorn is missed by the hungry creatures.

The bur oak is a shaggy tree, for it sheds its bark in big flakes, like the sycamore. The small branches are stout, and their bark is developed into corky wings, like the sweet gum. The tree is irregular in shape, too, its gnarled limbs are thrown out in any direction, and so the top is often unsymmetrical. But it is a rugged and picturesque tree, in spite of all its faults, and it adds beauty of an unusual kind to parks and woodlands.

In Sioux City, Iowa, an aged bur oak stands in Riverside Park. It is called “The Council Oak,” for it was a venerable tree in the days when the Indians lived on the banks of the Missouri River. Under this tree their chieftains used to meet the white men, and talk over the questions that interested both. Here treaties were drawn up and signed that kept peace between the red and white men.

I promise a great deal of pleasure to any one who plants a mossy-cup acorn. The seedling tree is wonderfully vigorous in growth. The leaves are often a foot long in the first years of the tree’s life. The blades are thick, lustrous above, and woolly lined, the finger lobes irregular, and two opposite, deep sinuses near the middle of the leaf cut it almost in two!
Before the tree is more than a sapling it blossoms and bears big acorns in their handsome mossy cups. There is no stage in the life of one of these oaks that is not beautiful and interesting.

This tree is found from Nova Scotia to Western Texas. It forms forests in Winnipeg, and “oak openings” in Minnesota and Dakota. It is as much at home in the hot, arid stretches of the plains of the West and Southwest as in the raw, damp air of the New England coasts. In the rich valley of the Ohio River it reached nearly two hundred feet in height in the virgin forests. Unlike many oaks, it may be safely transplanted while young.

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Leaves, mossy-cup acorns and warty twigs of the bur oak

The citizen of New Orleans takes his Northern visitors to Audubon Park, and points with pride to the giant live oak trees. He does not hesitate, for he knows that the noble pair called “George Washington,” and “Martha Washington,” though crippled now by tornadoes, are more noted the country over than any monument or building in this famous old city. In Charleston and other Southern cities it is the same. Famous old live oaks adorn the parks and avenues, and the same trees are planted year by year to take the places of the veterans when age and storms shall make an end of their long lives.

These trees wear a crown of green throughout the year. The leaves last but one year, but they cling to the twigs and remain green until they are gradually pushed off by the opening of new leafy shoots. In spring the new leaves are much brighter than the darker old ones. Everywhere the trees are draped with the sage-green ropes of “Spanish moss,” which is not a moss at all, but a flowering plant that steals its living by lodging its roots in crevices in the bark of trees.

The live oak acorns are dainty, dark-brown nuts, set in hoary, long-stemmed cups. Each year there is a good crop of acorns, and they are sweet, and pleasant to the taste. The Indians depended upon them for food, roasting or boiling them. They also skimmed the boiling pot to collect the oil, which the early colonists said was much like oil of almonds.

The “knees of oak” that early ship-builders used to brace the sides of vessels, were taken from live oak trees, where the great boughs spring out from the short, stout trunks. This natural joint is better than any bolted union of two pieces of timber. The scarcity of these trees makes it impossible now to supply these knees, but no steel frame serves the purpose quite so well. The wood is as beautiful as white oak for the making of handsome furniture, though it splits more easily, and is harder for the cabinet-maker to use.

The tree grows throughout the South to Texas; also in Mexico, and Lower California. Its Northern limit is Virginia.

A friend who has for a near neighbour the majestic McDonough Oak, patriarch among the noble live oaks of the Audubon Park, New Orleans, writes interestingly of the habits of this species.

“The live oak sheds its leaves in the spring, just before the new leaves open. So, for a brief time the tree stands leafless. In this period, however, the tree puts out catkins in great abundance, so that the tree does not appear bare. These catkins are light brown, and have a soft, velvety appearance, and a tree has an absolute change of colour. During this blossom time the splendid form of the trunk and the great limbs is revealed. When the new leaves appear, the framework of branch and bough is concealed by leafage so dense as to be impenetrable to sun or eye. The tree is a symmetrical, shining green dome. The crown of the McDonough oak is over two hundred feet in diameter.”

The post oak, a small, rugged tree, is noticeable in winter, because its leaves usually hang on until the open buds in spring push them off. The colour of this winter foliage is yellowish brown, and not at all striking nor beautiful. The bark is brown and deeply furrowed. The twigs wear a yellow fuzz. The leaves are coarse, stiff and rough, four to five inches long, tapering from three broad, squarish lobes to a narrow base, and a short leaf stalk. They are lined with brownish wool, and are dark green and shining above in summer.

The acorns of the post oak are borne in a plentiful annual crop. Each is dainty and trim, in a shallow cup of loose, blunt-pointed scales. The kernel is sweet. In the days when wild game roamed the woods, wild turkeys fattened on these acorns, and some people call the tree the “turkey oak.”

Another name for this tree is “iron oak,” for its wood is hard, and heavy, and close-grained. It makes admirable posts and railroad ties, because it does not rot in contact with water. It is used in boat-building, and for barrel staves. “Knees” of post oak (the angles between trunk and branch) form most admirable timbers to be used in the framework of boats.

The swamp white oak is a rugged and ragged tree, with drooping branches and crooked twigs, covered with greyish brown bark which peels in thin flakes from branches and trunk. This habit of shedding its bark in irregular plates reminds us strongly of the sycamore, which carries this habit to excess. The leaves of this oak are large, wedge-shaped at the base, wavy-toothed or lobed, and broadening towards the tips. They are dark green above, and lined with white down. The acorns are borne in pairs on long stems. The oval nut is hairy at its tip, and sits in a rough cup made of scales, sometimes fringed at the border. The kernel is sweet and eatable, not only for beasts, but for man. If one were lost in the woods, he need not starve nor die of thirst, if he is near a stream, and can get the fruit of a swamp white oak, which stands by the water side. He will do well to make a fire, and roast the acorns, which will improve their nutty flavour, and make them more digestible.

This white oak is more beautiful in May than at any other season of the year. The young leaves are pale green, and the tree top is illuminated by the silky hairs that line them. The whiteness of the down is dimmed as summer advances. In the autumn the leaves turn yellow, but never red.

The wood of this oak is not distinguished in the lumber trade from any other white oak. The demand for it for the building of houses and boats, and for agricultural implements and vehicles, is greater than the supply. It is too expensive now to be used as it was a few years ago, for fuel, railroad ties, and fence posts.

The chestnut oak has leaves which are much like those of the chestnut tree. They are larger, and wider, however, and have rounded lobes at the ends of the side veins, making a very regular wavy margin, compared with that of most oak leaves. The lining is often silky, and always much paler than the upper surface. This tree is an exception to the rule that the annual-fruited oaks have pale bark. This one has bark so dark in colour that it is often mistaken for one of the Black Oak Group, although its wavy leaf margins, and its annual crop of acorns, prove it to belong to the White Oak Group.

The acorns are very long, and smooth, and they sit in thin cups lined with down, and covered with small swollen scales. They are usually borne alone on short stems. This is one of the largest and sweetest acorns. The squirrels pack them among their winter’s stores.
The wood of chestnut oak is hard, and strong, and durable in contact with the soil. The bark is especially rich in tannic acid. For this reason many of the finest trees yield only tan bark, because the peelers take the bark, and leave the log to fall a prey to forest fires.

The black oak, which gives its name to the large group of biennial-fruited oaks, is one of our handsome, sturdy forest trees. It grows from Maine to Florida, and west to Minnesota, Kansas, and Eastern Texas. Its bark is very dark grey or brown, and thick, with rough, broken ridges and deep furrows. Under this outer layer is a yellow belt, rich in tannin. This gives the tree the name “yellow oak,” and since its bark is valuable in tanning leather, it is some times called the “tan bark oak.”

The tree is not graceful nor symmetrical, but there is a picturesqueness and strength about it that redeems its coarseness and irregularity. This species would be planted oftener for shade, were there not so many beautiful oaks to choose from. In the wild, however, a giant black oak is a noble feature of the landscape.

In early spring the large downy winter buds begin to swell, and soon the leaves push rapidly out. The whole tree top flushes crimson in the sunshine. The red glow is from the crinkly, half-awake baby leaves, whose brilliance is softened by a silky covering of white hairs. In a day the leaves turn green, and most of their silky covering is shed.

The bloom of the black oak consists of a fringe of yellow catkins at the base of each shoot, and pairs of red-tongued acorn flowers in the angles of some of the leaves. Back of the new shoot the half-grown acorns of the previous season are seen. In autumn the new crop is well along and the full-grown acorns, which have taken two seasons to ripen, are ready to be shed. Each kernel sits in a straight-sided cup of loosely shingled scales, which form a fringe at the margin. The kernel is bitter, and yellow, as it is in most of the species of the Black Oak Group.

The large, downy, pointed buds of this oak will often determine its name for us when we are confused by the shapes of the leaves. Often the red oak and the black oak “run together” in their leaf forms. To determine the tree’s name we must call in the buds, the acorns, and their cups, and the general shape of the trees, and consider all these points together.

Black oak leaves are thick, coarse, and leathery. Crumple one in your hand, and you cringe at the harsh scratching noise it makes. They vary from four to ten inches in length, and from two to six inches in breadth. The margins are deeply cut into seven or nine broad, bristly-toothed lobes, with rounded bays between. The upper surface is dark green in summer, shining and smooth, or sometimes hairy. The lining is brownish and a remnant of the scurfy down is found in the neighbourhood of the veins. In autumn these leaves turn brownish-yellow, but rarely show a tinge of red.

The bark of black oak is stripped and carried to the tan-yards. Or it furnishes a yellow dye, used in the printing of calicoes. The wood is used in house-building, and in the manufacture of furniture.

The red oak is the tree most likely to be mistaken for the black oak. The bark is brown, with a decided red tinge. The twigs are also reddish, and the wood is red-brown. The inner bark has the same tinge instead of the orange-coloured lining the black oak bark has.
The red oak is a large, stately tree, sometimes 150 feet in height, and far more symmetrical than the black oak. Its leaves vary greatly in the depth of their marginal clefts, but in general they are oval in outline, and their lobes and sinuses are triangular. These lobes always point forward, rather than outward, along the sides of the leaf, and they always end in the sharp, spiny points that belong to the leaves of all the trees that fall into the Black Oak Group. Red oak leaves are thinner than those of black oak, and not so harsh when crumpled in the hand. Their linings are pale green and smooth in summer. Their autumn colour is deep red.

The buds of the red oak are pointed, smooth, reddish, and about one-fourth of an inch long. They are much smaller, and lack the down of the buds of the black oak.

Red oak acorns are the most distinct feature of this species. They are large, often over an inch in length, and broad, and they sit in saucers, instead of cups. These saucers are made of close scales, and they curl in closely at the top as if to tighten their hold on the nut, which extends two-thirds its height above this rim. The kernel is white, and extremely bitter.

The scarlet oak need not be confused with either the red or black oaks, for it is a far more dainty tree than either in its trim trunk, graceful curving branches, very slim twigs, and deeply cut leaves. In form, these leaves are oval, but so much of the “cloth” is cut away by the four or six deep bays along the sides that a small amount of green is left to do leaf duty.

The slender lobes are strengthened by the branching veins, each of which ends in a spiny point. These almost skeleton leaves are beautifully lustrous and thin, a trifle paler beneath and sometimes hairy tufted at the veins. They are rarely six inches long, and the side lobes sometimes measure five inches from tip to tip. The leaf stems are long and flexible, and the whole tree top is as light and feathery and tremulous in a breeze as that of a honey locust or a willow. In autumn the scarlet oak blazes like a torch above the duller reds and browns of the woods, and keeps its brilliancy later than any other oak.

The acorn differs from the black oak in being smaller and daintier, and in having its cup drawn in tightly at the rim. The scales are smooth and close-pressed; the kernel white and bitter.

The pin oak has foliage much like the scarlet oak, but coarser and not so lustrous. Often a pin oak tree has leaves that approach the red oak in form, and these lead to confusion, if leaves alone are consulted in determining the name of the tree. There are better signs in any pin oak that set it apart from its larger-leaved relative. Consult the acorns. They are plump little nuts, as broad as long, rarely measuring one-half inch either way, pale brown, streaked with black in straight lines, down from the pointed tips, and they sit in shallow, saucer-like cups made of close reddish scales. As they fall, the nuts roll out of the cups, which are lined with hair. The kernel is white and bitter and yet, late in winter, it is very common to find them gnawed open by some hungry little four-foot, whose winter store threatens to run short.

The pin oak takes its name from the fact that its branches are thickly set with short, pin-like twigs, many of which die but do not fall. These stubs stay on for several years. This fact alone will soon enable us to recognise the tree from a distance. No other species is so close-twigged, and the symmetrical form of this tree is very striking in the winter. It is a pyramid with many small branches thrust out horizontally from the main shaft. Below the middle of the tree, the long branches have a downward thrust, and the lowest ones often sweep the ground. Above the middle of the tree the branches are horizontal, and they gradually become shorter, and the tree ends in a pointed tip. There is no oak that I know which has so much the pyramidal form of evergreens like the firs, hemlocks, and spruces.

On the avenues of the city of Washington, we shall find superb double rows of American trees. On one which leads to the Navy Yard, I remember the beautiful pin oaks, uniform in size, perfect in symmetry, that stood in a double row along the sides of the avenue. To the crowds of tourists who visit the capital city every year, I hope that this will be an object lesson. In most towns and cities every owner plants the trees he likes in front of his house, so our streets and avenues present a mixture of trees of all ages, sizes, kinds, and conditions. The better way is for the city to plant the same tree in double lines, the whole length of a street, as has of late years been done in Washington. One needs only to see these trees coming on, each year adding beauty and dignity to the city, to realise that such planting may be done easily anywhere in the country, where trees as beautiful as the pin oaks grow wild.

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The horizontal limbs of the pin oak form a regular pyramidal head

A Southern tree with slender twigs and narrow leaves like those of a willow, surprises us by bearing acorns! It is the willow oak, a beautiful, graceful tree for shade and for avenue planting. The tree naturally chooses wet ground, but it thrives where the soil is deep and well drained. I remember a fine large willow oak in John Bartram’s garden in Philadelphia, and a young tree in the Arnold Arboretum in Boston. This little one grows rapidly, but the frost nips its twigs in the winter. The species grows wild from New York southward, just back from the sea coast, to Texas. In swampy land, it is found from Missouri southward.

Willow oak acorns are downy, yellow-brown, and set in shallow saucer-shaped cups. The kernel is orange-yellow, and bitter. Half-grown acorns are found with the ripe ones on these trees, and the dark, rough bark agrees with others of the Black Oak Group. Though the leaves have rarely a side lobe, but are mostly narrow and plain-margined, the tip ends in a spine, as all black oak leaves should.

Text from:  Trees


under the terms of the Project Gutenberg License included
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Title: Trees Every Child Should Know
Easy Tree Studies for All Seasons of the Year

Author: Julia Ellen Rogers

Release Date: November 15, 2013 [EBook #44186]

Language: English

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Edited version LondonTreeSurgeons 2018