Popular Science Monthly/Volume 38/December 1890/Prairie Flowers of Late Autumn
By BYRON D. HALSTED,
PROFESSOR OF BOTANY IN RUTGERS COLLEGE, N. J.
IT is not easy to satisfactorily decide why some plants bloom in autumn, while others produce their flowers only in spring. To have hepaticas in April is as much a matter of common expectation as for August to bring the first golden-rods and October a gorgeous display of asters. An unwritten law of Nature has been conformed to, and the result is a floral time-piece of the seasons, so accurate in its wonderful mechanism that one only needs to see the bouquet of a school-girl returning from her Saturday afternoon ramble in the woods to know the month of the passing year. Some time ago (The Popular Science Monthly, May, 1887) the writer prepared a paper upon "Prairie Flowers of Early Spring," in which it was stated that the first blossoms of the season gained an advantage by being first. There is a mutual adaptation existing between flowers and insects that the most casual observer can not gainsay. It is not only an advantage, but in many cases a positive necessity, that flowers be visited by insects in order to secure that transfer of pollen from one blossom to another which results in fertilization. The modern accepted view of all floral display is that it serves the purpose of attracting insects, and acts as a contrivance by means of which the fertilization of a flower by its own pollen is prevented. Botanists of earlier days did not force this truth upon the attention of others, and many persons better qualified to judge of human than natural history arrived at the erroneous, if not somewhat selfish, conclusion that floral forms and colors were primarily to beautify the earth and render it a pleasant habitation for man. No one can for a moment doubt that flowers are beautiful, but beauty is a secondary matter so far as the gratifying of man's taste for beauty in forms and colors is concerned. It is so planned that the qualities which render the floral structures so well adapted to the peculiarities of the insects are the ones which at the same time render them beautiful and thereby contribute to the pleasure of man. In this adjustment we may see the working of an Infinite Mind able to combine the two elements of utility and beauty so completely that it is not extravagant to say they are often inseparable.
In the present paper the reader's attention is invited to some of the plants that continue to bloom after the fingers of Jack Frost have silently pulled down the dark curtain of the waning autumn and shut out the warmth of vitality from all the tender sorts of vegetation. The first day of October opened upon a landscape of varied hues, some of a most somber character, for late in September the leaves of the box-elder, for example, had been blasted by freezing and the vineyards were prematurely brown with the curled and dying foliage rustling in the breeze. Corn and other plants of a like subtropical nature, not previously harvested, were stricken lifeless by the low temperature, and house plants carelessly left out of doors melted away into a mass of rapid decay. As one looked about him the scene could but remind the observer of the Scripture injunction concerning the two women grinding at the mill. Two plants side by side had been growing with equal vigor, and both bespoke an equally long life, but one was taken and the other left. The reason for this is not easy to find.
Many mysteries flood the mind in contemplating the world of vegetable life, but none more thoroughly baffles the keenest observer as well as the most penetrating microscopist than that of hardiness. We freely use the word in ignorance, or worse, to conceal our ignorance, as physicians may employ longer terms among their admiring, awe-struck, ignorant patients, but when the thoughtful pause comes it brings us face to face with a half-clothed skeleton that nearly frightens all save the brazen-faced. We may attempt to explain the real meaning of hardiness in a dozen ways, and in the very offering of so many reasons we exhibit the weakness of all the arguments. If we say that it is due to denser structure, the statement is met with the bald-faced fact that the hardiest plants do not have necessarily the denser tissues. A box-elder, which is considered a type of hardiness, yields a wood less than half as heavy as the hickory. Of the sixteen sorts of trees in the United States with wood heavier than water, all are in the warmer portions of the country, where no winter tests their hold upon vitality. Perhaps it is as much the plan of one species to have its twigs killed back as it is for another to withstand the sudden changes of temperature and the severe cold. It demands a more than human penetration to decide that the horse-chestnut, with its large and well-protected terminal buds in autumn, is better adapted to its conditions than the raspberry, with young, immature wood and imperfect buds, which die before the spring-time comes. The two are working out the problem of existence along widely diverging lines. The tree grows slowly and builds for a century, while the bramble forms only transient stems and runs its chances of making all it can out of a favorable growing season. No one would care to say that a Rubus is less hardy than an Æsculus. They are not to be compared, and there the matter ends. If two species in the same genus have similar habits of growth, and one fails to bear the surrounding conditions while the other thrives, the case is very different, and it is more natural to seek the reason, for the answer, if it could be given, might be a blessing to every orchardist and gardener suffering from losses among his tender plants. And even here it may be that the explanation turns upon surroundings to which each plant has been subjected. We know that species migrate from the home of the parent as birds from the parental nest or the sheep from the fold. It is not difficult to believe that offspring from common stock in time develop progeny subjected to very unlike conditions. Under dissimilar circumstances they develop unlike tendencies; and when, after centuries, these new forms are again brought together through man's culture, while they may be outwardly the same, the one is tender while the other is not. It is a question of the resistive power which, whenever we reach for it, whether with the high-power lens or the chemist's test-tube, the result is much the same. This generation seeks after a sign, and it might do many worse things. It may be a long time before there will be a better test for hardiness than that which is applied when a plant is subjected to the actual conditions. At present there is no rule without innumerable exceptions, which not only "prove the rule," but prove that it is valueless. The Greenlander may easily fall a victim to smallpox, because, we say, his system has not been so situated as to develop the resistive power to this direful malady. The Northern man goes south and is stricken with a fever that does not cause death to those "to the manor born."
In the field we see the corn falls with the first hard frost, while the asters along the roadway hold their freshness and continue to blossom until early winter congeals the sap. Turn to the flower-garden, and we see many of our tender plants in the withered brownness of death, and by their side stands the Anterrhinum in the beauty of its pristine freshness, bearing its blossoms of every size from the minutest bud up to the full flower. The pelargonium has its dead branches intermingled with the living stems of the petunia. The moss-rose is lifeless upon the ground, while the prostrate verbena is fragrant with new blossoms. Snows come and go long after the Indian summer has been succeeded by the chill November days, and the pansies smile from among frosty fallen leaves. Death and life are closely associated, and, while we can not comprehend it all, there are few who would lose the exhilaration of a prolonged search for the sake of knowing it all at once.
Along my daily pathway have thronged the shepherd's-purse and the purslane. The former passed the winter as seedlings from self-sowed seed in early autumn, and closely hugged the frozen soil unprotected, or perchance benignly covered with a blanket of snow. When the November blasts are howling and whirling down the snows, some belated plants—or, more properly, some hasty specimens ahead of their time—are left blooming alone. The pepper-grass (Lepidium virginicum) is closely related to the shepherd's-purse, and has the same times and seasons and habits of growth. On the other hand, the hot-blooded purslane, which was able to sprawl at full length upon the superheated ground in August, and thrive, to the great annoyance of the tidy gardener, falls a lifeless victim at the first firm grasp of the frost-king. In its obeseness it blackens with the rising sun, and soon leaves little else behind except the thousands of almost microscopic seeds, for which the icy winter only seems to serve as a fitting introduction to new activities when the long-delaying spring arrives. Look into the vegetable garden, if you please, and recall the two classes of plants therein grown for the table. There are sorts, the seeds of which may be sown as soon as the ground can be worked; while other seeds are of the tender sort and can not be committed to the earth until the settled weather has come and the danger of the laggard frosts is past. Toward the end of the season there is a like distinction. In short, some of the garden favorites must make all their growth during warm weather, and perish with the frosts of autumn; while others can be gathered at pleasure, even left in the earth until 'the following spring, and improved by the seeming neglect. Of meadow and pasture crops there are few that flower later than the red clover. This may be found in full bloom until the snows cover the melliferous heads for the balance of the year. The alsike also is a late bloomer, but the white sort gives up much earlier.
Let us turn now to the wild plants which are in flower upon or after the first of October in the climate of central Iowa—a prairie region—where autumn is more than past its middle by that date. At the outset, it is manifest of the plants in flower that a large number belong to the sunflower family. Among the most conspicuous are the asters and golden-rods, and the most beautiful of them all is the Aster Novæ Angliæ. This is a common species, and because at home in New England—as the name indicates—is none the less attractive, and one, the charm of whose purple rays of the large heads never flags. I have been upon long tramps through the low meadow-land where this species is the chief blossom, and never tired of the variability which the many plants exhibit. The leaves are clasping as if a strong affection existed between the blade and the stem from which it sprang. Intermixed with this most richly attired of all the asters is the Riddell golden-rod (Solidago Riddellii); quite different from all the other Solidagos in having the stems clothed with long, smooth, narrow leaves, which gradually curve upward and then describe a half circle downward. The large clusters of flowers in the medium-sized heads have a depth of auriferous color which can not fail to attract all lovers of yellow. The golden-rod most nearly like the above is Solidago rigida, an earlier bloomer but holds its own against the early frosts. As the name suggests, the stem is large and stiff or rigid, the leaves are sessile, large, thick, and the heads of the blossoms form a broad, flat-topped inflorescence, standing three or more feet from the high, dry prairie soil. Among the other golden-rods were Solidago speciosa and the altogether common and yet far from the least attractive species, Solidago canadensis. This furnishes a serious puzzle to the careless student, but the lover of slight differences in plants finds in this species with its various varieties a subject of absorbing interest. Aster longifolia and A. multiflorus vie with each other in making the waste places bright and attractive during the October days, and exhibit their powers to resist the destructive agencies of the closing days of autumn by shaking their leafy stems and bright fresh heads of blossoms in the storms of bleak November. The three asters already named are among the last of all the prairie flowers, and seem to be full of life when the streams are icy in the morning and the sunny side of a log is a favorite haunt of the birds of winter.
Along the small brooks and over the lowland, where the fog damp and chill settle at early sunset, the great sunflower (Helianthus grosse-serratus) may wave its head, while around it is the retirement of the winter condition. Helenium autumnale, with its handsome heads, with lemon-yellow notched ray flowers and peculiar velvety decurrent leaves, is not common but attractive. We do not wonder that it lingers in the lap of early winter, because the atmosphere of its whole being is one of endurance, but of the quiet sort befitting the Quaker and not that of the bully.
But there are many late autumn plants scattered through other than the sunflower family. Along the streams and standing kneedeep in the wasted and decaying rubbish of the borders is the long, leafy stem of the Physostegia virginica, with its slender spike of showy rose and purplish-white blossoms. It is one of the mints in all save the minty quality, and for this peculiar lacking it is often a source of trouble to the tyro in classification. The flowers are complex, the stamens possess an abundance of hairs, in which the circulation of protoplasm may be seen; and, besides, insects visit them.
Of a very different type, perhaps more showy and certainly as interesting to the student of floral structures, is the great blue lobelia (Lobelia syphilitica), a frequenter of all low places, where its rank growth and bright deep blue render it a prominent object. This plant with its insect attendants has often furnished amusement for me by the half-hour. The insects seem always in haste, and dodge in and out of these blossoms with a methodical rapidity, each time receiving a new invoice of pollen to be scattered upon the stigmas of other blossoms subsequently visited. Among the most seemingly out-of-place blossoms as to time of appearing were those of the common blue violet. This is strictly one of the spring flowers, but with us for years it makes a second advent, and in some places blossoms so freely as to be no rarity. It has been used for classes of a hundred members for dissection in October. This favorite plant is not as well known in habit as it deserves. Its underground close-fertilized flowers, for example, are unseen, therefore passed by by those who only pick the showy aërial blossoms. The little low, round-leaved mallow, or prostrate mallow—in my boyhood days we called it "cheeses"—is one of our October flowers.
It will be seen that a fair share of the late autumn blossoms are weeds and useless plants. The May-weed (Anthemis cotula) is one of those which, if less common and without its rank odor, would be a very attractive plant in both foliage and flower; but, as it is, no one is anxious to give this wayside intruder any high place among the purely ornamental species. In like manner the mullein, or "great American velvet-leaf" as it is sometimes called in Europe (Verbascum thapsus),is a plant with some inherent attractions; but, owing to its obtrusive habit, combined with a coarseness and boldness, it can only rank with the weeds. It will accommodate itself remarkably to unfavorable conditions and come up blooming under all sorts of rough if not abusive treatment. There is a strict military air to this plant as well as to one of its October associates in the pasture (Verbena stricta). Both have stems much straighter than some ramrods, and one time a friend, seeing the mullein in great abundance upon rolling ground, remarked that they were like ten thousand men marching up a hill. The species of liatris, or blazing-stars, are of the same strict habit but vastly more showy. We have three species of these charming rose-purple composites, all of which flower late in summer and remain to display their marvels of beauty long after the tender plants have served their time.
Among all the late blossoms there are none for which I have a greater fondness than the gentians. They come, with their mingled purple and blue, at a time when those colors have become unusually rare, for they are never common at any time of year. Some of the species bear flowers that long seem upon the verge of coming into full bloom, and disappoint those who look for wide-open flowers. They are somewhat bell-shaped; into the plaited opening, otherwise nearly closed, the bee or other insect pushes its way in search of nectar and pollen. Upon the exit of the winged visitant the corolla again closes, to the exclusion of everything except its insect attendants. The most charming of all the species of this late-flowering genus is the celebrated fringed gentian, so named because its long corolla ends in a most delicate row of long, fine, hair-like projections, suggesting the heavy eyelashes of a beautiful girl. The tint of the whole blossom is a pure and delicate blue, caught, as it would seem, from some patch of October sky, margined by flecks of fleecy clouds. These gentians, as well as rich specimens of a cousin to the thoroughwort and boneset, with great clusters of pure white flowers, might be gathered any late autumn day, the former in the low prairie, the latter in the tangle of frost-bitten herbage in "the timber" along the water-courses. The boneset flowers suggested, in their exhibition of white, the approach of winter, when all the copse is covered with a mantle of snow and the stream is locked in the embrace of the frost-king.
One of the latest of the autumn prairie flowers—and one not found by me until drear November has come in the wake of Indian summer weather—is the ladies-tresses, an orchid of no striking beauty, but, in a region where orchids are rare and arriving after the eleventh hour, it has its full share of interest. The plants are single-stemmed, few-leaved, and the small, pure white flowers are so arranged upon the long spike as to assume a spiral inflorescence, from which fact the common name doubtless originated in the fertile mind of some imaginative lover of plants. If the witch-hazel had been a member of the prairie flora under consideration, it would have been in its place of honor at the close of this list; but, as it is, the orchid and the aster, the shepherd's-purse of the wayside and the prairie must vie with the pansy in the flower-garden for the last place in the floral calendar of the year.
The reasons assigned in a previous article for the early blooming of plants hold good here for those that develop their flowers late in the year, and can be briefly condensed into the expression that, in the experience of the species, it is probably found an advantage to be somewhat out of the season. A single store upon a side street may do as well as any one in the market-place, provided it is thoroughly accommodated to the situation: competition, or the absence of it, is likewise an element not to be ignored in the consideration of the time of blooming of flowers; and no one can but rejoice that all plants do not produce their blossoms during the same day or week or even month of the year.
[The above article has been prepared from notes taken by the writer while occupying the chair of botany in the Iowa Agricultural College.]