Trees Worth Knowing Part 3

A tree takes on in winter the temperature of the surrounding air. In cold weather the water in buds and trunk and cambium freezes solid.

Ice crystals form in the intercellular s.p.a.ces where they have ample room, and so they do no damage in their alternate freezing and thawing. The protoplasm stiffens in excessive cold, but when the thermometer rises, life stirs again. Motion, breathing, and feeding are essential to cell life.

It is hard to believe that buds freeze solid. But cut one open in a freezing cold room, and before you breathe upon it take a good look with a magnifier, and you should make out the ice crystals. The bark is actually frozen upon a stick of green stovewood. The sap that oozes out of the pith and heart wood was frozen, and dripped not at all until it was brought indoors.

What is meant by the freezing of fruit buds in winter, by which the peach crop is so often lost in Northern states? When spring opens, the warmth of the air wakes the sleeping buds. It thaws the ice in the intercellular s.p.a.ces, and the cells are quick to absorb the water they gave up when winter approached. The thawing of the ground surrounds the roots with moisture. Sap rises and flows into the utmost twig.

Warm days in January or February are able to deceive the tree to this extent. The sudden change back to winter again catches them. The plump cells are ruptured and killed by the "frost bite."

It is a bad plan to plant a tender kind of tree on the south side of a house or a wall. The direct and the reflected warmth of the sun forces its buds out too soon, and the late frosts cut them off. There is rarely a good yield on a tree so situated.

There is no miracle like "the burst of spring." Who has watched a tree by the window as its twigs began to shine in early March, and the buds to swell and show edges of green as their scales lengthened? Then the little shoot struggled out, casting off the hindering scales with the scandalous ingrat.i.tude characteristic of infancy. Feeble and very appealing are the limp baby leaves on the shoot, as tender and pale green as asparagus tips. But all that store of rich nutritive material is backing the enterprise. The palms are lifted into the air; they broaden and take on the texture of the perfect, mature leaf. Scarcely a day is required to outgrow the hesitation and inexperience of youth. The tree stands decked in its canopy of leaves, every one of which is ready and eager to a.s.sume the responsibilities it faces. The season of starch making has opened.

Cut some twigs of convenient trees in winter. Let them be good ones, with vigorous buds, and have them at least two feet long. You may test this statement I have made about the storing of food in the twigs, and the one about the unfolding of the leafy shoots. Get a number of them from the orchard--samples from cherry, plum, and apple trees; from maple and elm and any other familiar tree. Put them in jars of water and set them where they get the sun on a convenient window shelf. Give them plenty of water, and do not crowd them. It is not necessary to change the water, but cutting the ends slanting and under water every few days insures the unimpeded flow of the water up the stems and the more rapid development of the buds you are watching. When spring comes there are too many things that demand attention. The forcing of winter buds while yet it is winter is the ideal way to discover the trees'

most precious secrets.

PART II

THE NUT TREES

The Walnuts--The Hickories--The Beech--The Chestnuts--The Oaks--The White Oak Group--The Black Oak Group--The Horse-Chestnuts, or Buckeyes--The Lindens, or Ba.s.swoods

THE WALNUTS

Hickories are included with their near relatives, the walnuts, in one of the most important of all our native tree groups. They are distinct, yet they have many traits in common--the flowers and the nut fruits, the hard resinous wood, with aromatic sap and leaves of many leaflets, instead of a single blade.

The walnuts are decidedly "worth knowing." All produce valuable timber and edible nuts, and all are good shade trees. Four native walnuts are well known in this country, for in October, every tree in every bit of woods is likely to be visited by school boys with bags, eager to gather the nuts before some other boy finds the tree, and thus establishes a prior claim upon it. The curiously gnawed sh.e.l.ls outside the winter storehouse of some furry woods-dweller reveal the most successful compet.i.tor boys have, the constant watcher of the nut trees, a harvester who works at nothing else while the season is on.

=The Southwestern Walnut=

_Juglans rupestris_, Engelm.

The walnut of the Southwest grows into a spreading, luxuriant tree, where its roots find water. But on the canyon sides, and higher on mountain slopes, it becomes a stunted shrub, because of lack of moisture.

The nut is smaller than that of the eastern walnuts and has a thick sh.e.l.l, but the kernel is sweet and keeps its rich flavor for a long time. The Mexicans and Indians are glad to have this nut added to the stores they gather for their winter food.

One striking feature of this tree is the pale, cottony down on its twigs, which sometimes persists three or four years. The long limbs droop at the extremities, almost deserving to be called "weeping." But nothing could be more cheerful in color than the yellow-green foliage, shining in the sun, against the white bark of the tree. In autumn the foliage turns bright yellow. A specimen, much admired, grows in the Arnold Arboretum in Boston.

=The California Walnut=

_J. californica_, Wats.

The California walnut is a stocky, round-headed tree, with heavy, drooping branches, and bark that is white and smooth on limbs and on trunks of young trees. Ultimately the trunk turns nearly black, and is checked into broad, irregular ridges. In bottom lands, along the courses of rivers, back thirty miles from the coast, these trees are found, from the Sacramento Valley to the southern slopes of the San Bernardino Mountains.

The foliage is bright pale green, feathery, the leaflets often curved to sickle form, showing paler silky linings. Californians admire and plant this tree for shade and ornament. Its greatest value is as a hardy stock upon which the "English" walnut is grafted by nurserymen, for planting orchards of this commercial nut. The fruit of the native nut is excellent, but it cannot compete with the thin-sh.e.l.led nut that came from Persia, _via_ England.

=The b.u.t.ternut, White Walnut, or Oilnut=

_J. cinerea_, Linn.

In eastern woods the b.u.t.ternut is known by its long, pointed nuts, with deeply and raggedly sculptured sh.e.l.ls, in fuzzy, clammy, sticky husks that stain the hands of him who attempts to get at the oily meat before the husks are dry. This dark stain was an important dye in the time when homespun cotton cloth was worn by men and boys. The modern khaki resembles in color the "b.u.t.ternut jeans," in which backwoods regiments of the Civil War were clad. b.u.t.ternut husks and bark yield also a drug of cathartic properties.

Pickling green oilnuts in their husks is a housewifely industry, on the summer programme of many housewives still, if the woods near by furnish the raw material for employing her great-grandmother's recipe, brought from England, or perhaps from France. The green nuts are tested with a knitting needle. If it goes through them with no difficulty, and yet the nuts are of good size, they are ready.

Vigorous rubbing removes the fuzz after the nuts are scalded. Then they are pickled whole, in spiced vinegar, and are a rare, delectable relish with meats for the winter table.

[Ill.u.s.tration: WEEPING BEECH

_See page 42_]

[Ill.u.s.tration: BLACK WALNUT

_See page 31_]

A b.u.t.ternut tree, beside the road, or elsewhere, with room to grow, has a short trunk, and a low, broad head, with a downward droop to the horizontal limbs. The bark is light brown, the limbs grayish green, the twigs and leaves all ooze a clammy, waxy, aromatic sap, and are covered with fine hairs of velvety abundance.

Because it is low and rather wayward in growth, late to leaf out in spring, and early to shed its leaves in summer, the b.u.t.ternut is not a good street tree. It breaks easily in the wind, and crippled trees are more common than well-grown specimens. Insect and fungous enemies beset the species, and take advantage of breaks to invade the twigs through the chambered pith. Short-lived trees they are, whose brown, satiny wood is used in cabinet work, but is not plentiful.

=The Black Walnut=

_J. nigra_, Linn.

The black walnut (_see ill.u.s.trations, pages 31, 70_) is the second species east of the Rocky Mountains, and the tree chiefly depended upon, during the century just closed, by the makers of furniture of the more expensive grades. Black walnut wood is brown, with purplish tones in it, and a silvery l.u.s.tre, when polished. Its hardness and strength commend it to the boat and ship builder. Gunstock factories use quant.i.ties of this wood. In furniture and interior woodwork, the curly walnut, found in the old stumps of trees cut long before, is especially sought for veneering panels. Old furniture, of designs that have pa.s.sed out, are often sold to the factories, and their seasoned wood cut thin for veneering.

Walnut trees one hundred and fifty feet high were not uncommon in the forests primeval, in the basin of the Ohio and Wabash rivers. These giants held up their majestic heads far over the tops of oaks and maples in the woods. They were slaughtered, rolled together, and burned by the pioneers, clearing the land for agriculture. These men had a special grudge against walnut trees, they were so stubborn--so hard to make away with. How unfortunate it is that our ancestors had the patience to go forward and conquer the unconquerable ones. Had they weakly surrendered, and let these trees stand, we should have had them for the various uses to which we put the finest lumber trees to-day.

Unhappily, the growing of young trees has not been extensively undertaken to replace those destroyed. The newer forestry is awake to the need, and the loss may be made good, from this time forward.

The black walnut is nearly globular, deeply sculptured, with a sweet nut rich in oil, very good if one eats but a few at a time. Locally, they find their way to market, but they soon become rancid in the grocer's barrel. At home, boys spread them, in their smooth, yellow-pitted husks, on the roof of the woodshed, for instance, so the husks can dry while the nuts are seasoning. No walnut opens its husk in regular segments, as the hickories all do. But the husking is not hard. The thick sh.e.l.ls require careful management of the hammer or nut-cracker, to avoid breaking the meats.

Dark as is its wood and bark, no walnut tree in full leaf is sombre.

The foliage is bright, l.u.s.trous, yellow-green, graceful, dancing. A majestic tree, with a luxuriant crown from May till September, this walnut needs room to display its notable contour and size. It deserves more popularity than it enjoys as a tree for parks. No tree is more interesting to watch as it grows.

The bitter spongy husk deters the squirrels from gnawing into the nut until the husk is dry and brittle. Hidden in the ground, the sh.e.l.l absorbs moisture, and winter frost cracks it, by the gentle but irresistible force of expanding particles of water as they turn to ice. So the plantlet has no hindrance to its growth when spring opens.

Imitating nature, the nurseryman lays his walnuts and b.u.t.ternuts in a bed of sand or gravel, one layer above another, and lets the rain and the cold do the rest. In spring the "stratified" nuts are ready for planting. Sometimes careful cracking of the sh.e.l.l prepares the nut to sprout when planted.

The j.a.panese walnuts (_J. Sieboldiana_ and _J. cordiformis_) are grown to a limited extent in states where the English walnut is not hardy.

They are b.u.t.ternuts, and very much superior to our native species. A Manchurian walnut has been successfully introduced, but few people but the pioneers in nut culture know anything about these exotic species.

South America and the West Indies have native species. So we shall not be surprised, in our travels, to find walnuts in the woods of many continents.

=The English Walnut=