CHAPTER VI

THE TREES

I think that I shall never see

A poem lovely as a tree.

A tree whose hungry mouth is prest
Against the earth's sweet flowing breast;
A tree that looks at God all day,
And lifts her leafy arms to pray;
A tree that may in summer wear
A nest of robins in her hair;
Upon whose bosom snow has lain;
Who intimately lives with rain.
Poems are made by fools like me,
But only God can make a tree.

-JOYCE KILMER.

The Outdoor Sleeper had rolled his couch over to the far end of the porch and, half reclining on top of its soft folds, was indulging in a restful contemplation of the picture Nature presented for his delectation on a Saturday afternoon in early April.

Six months previously he had first sought the saving influences of the great outdoors, supplemented with its complement of rest and good food; and now, with that comfortable feeling of health regained, he looked out on the world through rose-colored glasses and "saw that it was good."

A short distance from the sleeping porch stands a fine old chestnut, fortunately spared from the blight which is slowly exterminating this species in the United States. Next may be seen a couple plum trees, then a silver maple, a pear tree, and down the road leading to the pike, tall, straight poplars, with an occasional blackheart cherry, Norway maple, or honey locust. South of the house is a small orchard, containing about twenty-five fruit trees, principally peach, pear, apple and cherry. Along the little lane which runs by the, garden, sassafras, wild cherry, sumac, chinquapin, and ailanthus are flourishing, together with tangled vines overhanging the straggling fence, and other small growth, till the lane disappears around the bend of the hill where it crosses a small brook merrily making its way to the creek of larger proportions that flows alongside the old stone mill, miles away.

While he had an appreciative eye for a beautiful landscape, his opportunities for absorbing the lore of the forest had been limited, as his avocation called him to the city, a dozen miles or so to the south, where he had been born and reared. It was therefore with real delight that he now from his point of vantage on the sleeping porch turned his attention to matters arboreal during the short period preceding dusk and occasionally from early dawn until seven, at which hour he arose for the day in order to catch the early trolley to town.

It is an open question whether spring, with its newborn loveliness, is the prettiest time of the year or whether autumn is not more attractive in all its manifold and luxuriant coloring.

Our open-air devotee settled the matter to his own satisfaction by deciding in favor of the former, and apparently with good reason. Beauty in any form always appealed to him, and he readily recognized it when the trees were "blushing with their first tender colors" in the spring and new wonders were revealed to him every day in bud and blossom, leaf and flower.

From the first pink tinting of the maples in March, forming a harmonious contrast to the early emerald of the willows, till the mulberries donned their final coming-out dress of modest brown and plushlike green late in May, while the locusts were still revelling in their seeming snow-flecked garments, the new phases of the various species as they developed afforded him constant entertainment and delight.

He learned that the first trees to don their spring dress are the pussy willow, which exhibits its silky catkins in the late winter or earliest spring, just before the appearance of its bright green leaves, and the weeping willow, the bark of which ealy in March turns from a rusty gray to a green lustre as the sap begins to flow upward and the long, slender, pendulous branches take on their narrow, drooping leaves.

The redbud or Judas tree, whose pink and purple flowers appear before its heart-shaped leaves, displays its loveliness in early April, when the fuzzy, silvery-gray catkins of the poplar are floating to the ground.

Next is noted the round-topped red maple, the spreading branches and bright green foliage of which provide airy mansions for the birds after its samaras or keys, seeds with wings, fall in May. At this time also are noticed the pairs of winged seeds on the silver maple that separate singly at the base and flutter in graceful spirals towards the earth.

In rapid succession are seen the crabapple, scattering the fragrance of its white and rosypink blossoms just after its leaves open in April; the birch-bark maple, whose dainty delicacy easily marks it the aristocrat of the lawn; the white poplar, its tremulous leaves quaking with the slightest breeze; the sweet gum; the dark green magnolia; the black, the white, and the red ash; the tall chestnut; and the stately elm.

Then come the purple-flowering dogwood, prettiest tree of spring; the beech, with its velvety, bluish-green leaves; the white and brownish bark-peeling sycamore; the linden, flowering in June; and the dark, purple-leaved plum.

The luscious-fruited mulberry, blossoming in April, develops well in advance of its plebeian cousin of the non-edible variety, with the reddish-brown bark whose partly-scalloped, broad leaves slowly unfold during May and June.

The malodorous ailanthus, or Paradise tree, joins the procession with sets of long, narrow leaves resembling those of the walnut; together with the majestic white and black oaks; the sturdy hickories; and the graceful pin oak, the spurlike twigs of which account for its

name.

And last of all, to complete Nature's greening, the lustrous, feather-leaved, black walnut makes its bow in company with the silver-bark birch, exquisite of the woods, and the sweetscented locust, with its lacy, fernlike new leaf and snowy blossoms.

Daily observation teaches him to know these friendly neighbors more intimately, and their characteristics and many beautiful traits are in time to him an open book, for, like Duke Senior in the Forest of Arden, he is philosopher enough to perceive that there are "tongues in trees, books in the running brooks, sermons in stones, and good in everything."

The majority of the fruit trees flower early in the spring, usually before the leaves appear, and their dainty blossoms form a charming picture in addition to yielding a delightful fragrance. The apple blossoms are usually white with a red tinge or blush; the peach pink; the pear, plum, and cherry white; and the quince, which flowers later, a delicate shell pink.

The walnut and the birch, which are the last in leaf, are likewise the first to lose their summer finery, being closely followed by the poplar and the maples.

The weeping willow, like the robin, which is the first bird to be heard in the morning and the last to cease its song at night, is the first to show its green leaves in the spring and the last to lose them in the fall, the emerald remaining until the first heavy frost in November and then slowly turning russet-brown until its complete defoliation in December.

When summer's leafy screen begins to lose its prevailing soft hue, as the green-forming chlorophyll is withdrawn from the foliage, Nature dips her brush in every color on the palette and provides rich and royal robes for her forest children.

The first tree to don its fall garb is the gum, selecting a brilliant red, intermingled with gold. The dogwood soon follows with an exquisite costume of maroon, a brownishred, or dark claret interspersed with green and yellow.

The poplar and red ash choose a light yellow, the hickory a golden yellow, the chestnut a tawny yellow, and the birch a russet yellow.

The silver maple is gowned in green and yellow, the sugar maple yellow and red, the shell bark and black oak a brownish yellow, and the wild cherry, locust, walnut, Norway maple, and redbud in more or less of the same golden tint.

The sassafras takes on an orange, red and purple; while the water oak is content with a modest tan, the catalpa brown and tan, the horse chestnut rusty brown, and the magnolia and hollyhock a dark brown.

The scarlet maple, showiest of the fall trees, puts on a dazzling coat of carmine, yellow and

green; the white oak and the white ash a cloak of purple; and the red oak and scarlet oak are encrimsoned in ruddy suits reflecting the glories of sunset.

In addition to preserving our watersheds, preventing erosion of the soil, furnishing timber for many articles of commerce, and bestowing grateful shade by its sheltering arms from the oppression of sultry summer days, one of the chief functions of the tree is embodied in the great quantities of ozone daily exhaled by its many leaves, for ozone, as we know, is one of the most necessary sustenants of life, and, as may be readily inferred, the man out of doors receives his portion in good and generous measure.

Also from the sleeping porch, which commanded a good view of the lawn and garden, it was an easy matter for him to observe that the first flower in spring to peep above the erstwhile frozen surface of the earth was the tiny snowdrop, followed in quick succession by the yellow crocus, jonquil and daffodil, the white narcissus, the beautifully colored tulip and hyacinth, and the dainty lily of the valley with its exquisite fragrance.

The pink and red ramblers climbing upon the trellis gladdened his eyes with their luxuriant bloom. The decorative shrubbery around the house put forth its new leaves, later revealing the pink beauty of the flowering almond, the fiery-red inflorescence of the burning bush, the creamy white globes of the snowball, the delicate purple of the early wistaria, the yellow of the jessamine, the golden-leaved mock-orange, the virginal grace of the bridal wreath, the daintiness of the spirea, and the shell-pink loveliness of the weigelia.

The delicious perfume of the honeysuckle, lilacs and roses borne on the early morning air and the iridescent colors of the peonies, hollyhock, myrtle and laurel also agreeably pleased his senses.

As the season wore on came the tall cannas, the scarlet sage, the golden-glow, the fragile cosmos, the dahlias, asters and chrysanthe

bacteria of disease, like the bacillus of diphtheria or the bacillus of tetanus, will likewise bring about grave symptoms, or even death, in any normal man and the individuals of several animal species. These substances are therefore toxins.

TUBERCULIN NOT A POISON

But no tuberculin has ever exerted such an effect. The fact of importance is that tuberculin is perfectly inert and harmless for any man or animal, unless the man or animal is tuberculous. Relatively enormous amounts may be administered with perfect impunity: the effect will be no more disastrous than if a similar quantity of milk were given the animal. I have myself injected 30 cc. (about a fluid ounce) of a tuberculin into the veins of a normal guinea pig that weighed less than a pound; and the animal was not made ill thereby. Hamburger, of Vienna, gave young infants 1 cc. at close intervals repeatedly over a long period. They remained in perfect health. Yet one-millionth of 1 cc. has frequently been known to make a human adult ill, provided the latter had tuberculosis. Scores of investigators have tried to wring from tubercle bacilli some specific toxin. All have failed. It is true that a certain few have reported that after complicated chemical treatment of the bacilli they had obtained a substance that apparently poisoned animals. And several of these men have therefore maintained that they had isolated a toxin. But such reasoning is shortsighted and unfair. From a chemical point of view, all bacteria are very complex and highly organized bodies, made up of many more elementary constituents which may of themselves be poisonous. By methods of cleavage or extraction one or more of these simpler, yet poisonous, substances might conceivably be obtained; yet, because of this, we would not in the least be justified in speaking of these latter as being specific toxins or poisons of the original substance. Common table salt is a simple chemical substance, made up of the metal sodium and the gas chlorine. By simple chemical manipulations it may be resolved into its two elements. No one would think of classing common salt as a poison. Yet chlorine is highly poisonous, and so, to a much less extent, is sodium. Sodium and chlorine exist, of course, in thousands of other substances and are therefore not specific to common salt. The case of anyone who has asserted that by chemical methods he has obtained a peculiar intoxicating substance for tuberculin or tubercle bacilli is to date not a whit different from that of the man who would make a similar claim concerning common salt. We went through our period of regarding tuberculin as a toxin or as containing a toxin. It lasted many years. For a number of years too many sought to obtain the specific antitoxin to combat this hypothetical toxin. Most of these men followed the procedure that had yielded such signal results in diphtheria.*

* See May, 1920, Essay.

Some big claims of success were made. But I do not believe that there is a single informed person who to-day would agree that anyone has ever obtained anything that has the least antitoxic power against tuberculin or tubercle bacilli. During the eighteen-nineties, Baldwin and Trudeau, of Saranac Lake, devoted several years to experimental studies of this nature, and ended by failing to elaborate any material that acted like an antitoxin. The fact that no antitoxin can be obtained is one more reason against the likelihood of there being a toxin.

Yet tuberculous animals are made ill by very minute amounts of tuberculin-in the case of man sometimes by one-thousandth of a milligram of old tuberculin. And, as we have said in the preceding essay, such men by careful management can now and then be brought to endure one thousand, ten thousand or even one hundred thousand times the dose that once made them ill. Here are two circumstances that apparently bear an exact resemblance to two well-known and scientifically established facts in regard to diphtheria-to the action of the latter's toxin and the substance antagonistic to the toxin.

But, as has been said above, the important difference lies in the fact that for the nontuberculous animal tuberculin is perfectly harmless, while for the non-diphtheritic animal (one, too, that has not had antitoxin) diphtheria toxin is powerfully poisonous.

No less striking and important, too, is the following contrast between the effects of diphtheria toxin and tuberculin on the normal animal body. If diphtheria toxin be given repeatedly to a non-diphtheritic (or diphtheritic) animal, the latter's tolerance to it is increased. But if tuberculin be given repeatedly to a non-tuberculous individual, the animal's tolerance is diminished. In other words, repeated injection of tuberculin renders an animal hypersensitive to it. This is certainly true with non-tuberculous animals. And since the tolerance of these is lowered by repeated applications of tuberculin, we must assume that the same thing happens in tuberculous animals. In other words, there is no immunity to tuberculin obtainable in any animals. Repeated applications bring about only the very reverse of immunity, a diminution of tolerance. Differently stated, the so-called tolerance to tuberculin which tuberculous animals acquire is (immunologically speaking) no tolerance at all. It is only an apparent, not a real, phenomenon, that has been deluding us.