Springtime

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Title:     Springtime
Author: Francis Darwin [More Titles by Darwin]

"Why, then comes in the sweet o’ the year."
--Autolycus’ Song.

Governesses used to tell us that the seasons of the year each consist of three months, and of these March, April, and May make the springtime. I should like to break the symmetry, and give February to spring, which would then include February, March, April, and May. It has been said that winter is but autumn "shyly shaking hands with spring." We will, accordingly, make winter a short link of two months—an autumnal and a vernal hand—December and January. It is a little sad for autumn to have to make room for chill November alongside of the happier months of September and October. But autumn is a season of decadence and cannot justly complain.

The autumnal flowers, which may be allowed to figure as a prelude to spring, are few in number. My favourite is lady’s tresses (Spiranthes), so called from the spiral twist in its inflorescence, which suggests braided hair. Gentiana amarella I should like to include, but its flowering-time is from 12th August to 8th September, and summer has the stronger claim on it. Other autumnal flowers are laurustinus and ivy. If we go by the mean date nothing flowers in October or November, and in December only the Christmas rose (Helleborus niger) is recorded by Blomefield.

But the autumn months have a glory of their own which may vie with the brightest hues of flowers. This great and beautiful panorama begins with the yellowing of the lime-leaves, which may occur as early as 17th August, but on the average is seen on 14th September. It is followed towards the end of September by a brown tint, showing itself in the leaves of the horse-chestnut. It is appropriate that these two species, which are not indigenous, {2} should be the first to fade into glory. But I must not insist on the point, for we see wych-elm leaves fall 24th September, while the date for the common elm is 28th October; and the elm is a foreigner compared to the wych-elm, and retains a mark of its alien origin in not setting seeds.

The syringa (Philadelphus) is another foreigner, which early shows autumnal tints—yellowing on 27th September. Then follow some native trees: the beech and birch both turning yellow on 1st October, and being followed by the maple on 7th October. I like the motherliness of the half-grown beech, who refuses to drop her dead leaves in autumn, hoping (as I imagine) that they will shelter her tender leaves in the chilly springtime. The older beeches give up this anxious care, and doubtless laugh among themselves over the fussiness of young mothers. They forget, no doubt, that in the scrub at the feet of their own boles the habit persists.

With regard to the fall of leaves, the sycamore begins to lose them 2nd October; birch and cherry, 8th October; maple and walnut, 12th October; aspen, 13th October; beech and elder, 13th October; ash, 14th October; Lombardy poplar and Virginian creeper, 18th October; honeysuckle, 22nd October; hazel, 26th October; elm, 28th October; whitethorn, 30th October; plane, 3rd November. Judging by a single observation of Blomefield, the larch is the last performer in the drama of autumn. It turns yellow on 8th November, and its leaves fall 15th November.

Blomefield {3} records that on 29th November the trees are "everywhere stript of leaves," so that some sort of colour-drama has been in progress from the middle of September to the end of November. It may be objected that what has been said of autumn is but a catalogue of names and dates. And this is true enough; but when we realise the glory of autumnal decadence, it seems (however baldly recounted) to be a fitting prelude to the great outbreak of new life—green leaves and bright flowers that spring gives us.

In Blomefield’s "Calendar" the difference between December and January is exaggerated. For, as it stands, it suggests that plants know that a new year has begun, and all burst into flower on 1st January. But that careful naturalist points out {4a} "all those phenomena which are referred to 1st January, as the earliest date, may be considered as occasionally showing themselves in December of the previous year."

The plants that bloom in winter, i.e. December and January, are few enough. The Christmas rose gives us its white or pink flowers in December, and the primrose may flower in the first days of January—indeed, I seem to remember it in Kent before Christmas, but I will not answer for it. According to Blomefield, the honour of being the first plant to awake must be given to the honeysuckle (Lonicera caprifolium), which unfolds its leaves between 1st January and 22nd February, i.e. on 21st January on the average. This bold behaviour is all the more to its credit since it is said by Hooker {4b} to be a naturalised plant.

Then follow in order the flowers of furze, hazel, winter aconite (Eranthis), hellebore (H. fœtidus), daisy, and snowdrop; so that the winter flowers make a most pleasant show, and tempt us to raise January to the rank of the first month of springtime—but we must allow the credit to be justly due to winter. In winter, too, we must be grateful to the ivy of the bare hedgerows shining in the sun, its leaves glistening like the simple jewels of a savage.

With February, we are agreed that spring comes in, but it is a springtime that keeps something of the graveness of winter: though, when the silver sunshine begins to be decorated with the singing of birds, we must call it spring.

In February, too, the roads are no longer edged with dead white grass, but show the fresh green of wayside plants—cow-weed, nettle, dock, and cleavers.

The trees still stand naked, their leaf-buds waiting for a better season. I like to think of wintering plants not as being asleep, but rather as silent. They sing with all their green tongues when spring releases them from the cupboards (which we call buds) where she has kept them safe.

The service-tree is a hardy creature, for its buds are naked and unprotected, like Pampas Indians who are proud of sleeping uncovered, and of seeing, as they rise, their forms outlined in the hoar-frost. I have only recently noticed the purple tint of alder-buds; {5} and I am reminded of the character in Cranford, who needs Tennyson’s words "Black as ash-buds in March" to teach him the fact. Some trees show their flowers early. For instance, the hanging tassels of the hazel, from which the dusty pollen can be shaken out, and the tiny red tufts which are all the female flower has to show. The alder, too, has a brave crowd of lambs’ tails. The elm should flower about the middle of March, and its pink stamens make a pleasant sight. These plants are called anemophilous—that is, wind-loving, as though grateful to the wind for carrying their pollen without payment. I can imagine that the plants employing insects to carry pollen from one to another feel superior to the wind-fertilised clan. We may fancy the duckweed (speaking of the pine) to say: "Of course, he is very big and of an ancient family, but for that very reason he is primitive in his habits. I know he boasts that he employs the winds of heaven as marriage priests, but we are served by the animal kingdom in our unions—and that, you must allow, is something to be proud of." {6} But duckweeds grow so crowded together that they are probably fertilised, to a great extent, by contact with their neighbours, without aid from the animal kingdom. We may also imagine the duckweed reproving the pine for his extravagance in the matter of pollen production. This, however, is necessary, because the pollen being sown broadcast by the wind, it is a matter of chance whether or not a grain reaches the stigma of its own species, and the chance of its doing so is clearly increased by multiplying the number of pollen-grains produced. Enormous quantities of the precious dust are wasted by this prodigality. We read of pollen swept from the decks of ships, or coating with a yellow scum lakes hidden among Tyrolean pinewoods. Pollen is so largely dispersed in the air that it has been supposed to be a cause of hay-fever.

Blackley found, by means of a sticky plate, which could be exposed and covered again, when raised high in the air on a kite, that pollen is dispersed to considerable altitudes. Wherever vegetable débris collects, pollen-grains may be found. Kerner found them, together with wind-borne seeds and scales of butterflies’ wings, sticking to the ice in remote Alpine glaciers.

Another characteristic of wind-borne pollen is dryness or dustiness; the grains are smooth, not sculptured like the pollen meant to be carried by insects; nor are they sticky or oily, as is often the case with entomophilous pollen. The advantage to the plan is obvious; the grains, from the absence of the burr-like quality, or of any other kind of adhesiveness, do not tend to hold together in clumps, but separate easily from one another, and float all the more easily. {7}

Several adaptations are found to favour the dispersal of the pollen. Wind-fertilised plants are generally tall; thus in Europe, at least, the commonest representatives of the class are shrubs or trees—witness the fir-trees, yew, juniper, oak, hazel, birch. And where the plants are lowly—e.g., grasses and sedges, and the plantains—the flowers are more or less raised up on the haulm. An exception must be made of some water-plants—e.g., the Potamogetons, where the flower-stalk is but slightly raised above the surface.

Wind-fertilised plants have many characteristics which favour the dispersal of the pollen. The grasses have long pendent stamens, and versatile anthers, from which the pollen is easily shaken out by the wind. There are, of course, exceptions to these generalisations. Such plants as Hippuris and Salicornia have no particular adaptations: the filaments are short, and the plants themselves are not of sufficient height to be able to scatter forth their pollen efficiently by the mere bending of their stems. The need for exposure to the wind is shown in another way—namely, by the habit of the Cupuliferæ (oak, hazel, etc.), of flowering before the leaves appear; this not only favours the start of the pollen on its flight, but is probably still more useful in increasing its chance of reaching the stigma.

If the pollen is exposed to the wind it will be liable to be wetted and injured. Catkins—such as those of the walnut or hazel—give some protection to the pollen, since the stamens are covered in by tile-like scales; but where—as in the grasses and plantains—the anthers hang far out of the flowers, the pollen is easily injured. Some of the cereals protect themselves against injury by means of a remarkably rapid growth of the filaments; thus the anthers remain hidden within the flowers until the last moment, and, under the influence of a warm sunny morning, rapidly protrude themselves. If the scales of the flower are artificially separated, the growth can be produced by warmth and moisture; Askenasy describes a trick of country children, who put ears of rye in their mouths and thus produce a miraculous growth of stamens. The growth or rapid turgescence takes place, according to the same writer, at the pace of one millimetre in three minutes.

The explosive male flowers of the nettle have a somewhat similar meaning. The young stamen is bent so that the upper end of the anther touches the base of the filament. On the inner concave side of the stamen are large cells, whose turgescence tends to unfold the filament: I do not know by what means the unfolding is prevented, but whatever the cause may be, it is at last overcome and the stamen uncurls with a jerk, and scatters forth the pollen. Here, as in the rye, the pollen is protected until the actual moment when it starts on its voyage through the air.

Another of the Nettle tribe, Pilea serpyllifolia—a plant often cultivated in our greenhouses—is also explosive, and its little puffs of smoke-like pollen have gained for it the popular name of the artillery plant. Its power of explosion must be of value to it as counterbalancing the disadvantage, to a wind-fertilised plant, of such a lowly habit.

The adaptations found in the female organs are chiefly such as increase the surface capable of receiving the pollen, and therefore increase the chance of fertilisation. A big stigmatic surface is common: not only is the receptive part of the style large, but it usually bears very large stigmatic papillæ, which gives a velvety hoary look to this type of stigma. In the grasses the three divisions of the stigma are always more or less conspicuous; and reach a climax, in this respect, in the huge beard-like tangle of the maize.

Some of the most interesting cases of wind fertilisation are those in which an isolated instance occurs in a Natural Order otherwise served by insects. Thus in the Rosaceæ, Poterium sanguisorba is wind fertilised, and has long pendent stamens, and a tufted stigma; while the closely allied Sanguisorba officinalis, although it secretes nectar (and this can only mean that it hopes to attract insects), retains the tufted stigma of its anemophilous relatives.

In the case of the Kerguelen cabbage (Pringlea antiscorbutica), the cause of its degeneration seems to be the want of winged insects on the wind-blown shores on which it grows. It has acquired some anemophilous characters—e.g., increased stigmatic surface and exserted anthers. Its flowers are inconspicuous like those of wind-fertilised plants in general, and it seems in fair way to lose its petals altogether—many flowers only retaining a single one. The entomophilous ancestry of Pringlea is clearly shown by the occasional remnants of coloured markings in the petals, like those which in other flowers serve as finger-posts to visiting-insects, and are called nectar-guides.

But these are digressions—sidepaths of tempting detail which have lured me from the straight highway. However, they have brought me back to the main road.

In Blomefield’s Observations in Natural History (p. 332), he points out that "however much the seasons may differ in different years, the phenomena generally follow one another in the same order. And it follows that those which occur together any one year, will occur at or nearly [at] the same time every other." This indeed is what we might expect, from the circumstances of any interruption in the time of their occurrence, due to seasonal influence, necessarily affecting them all equally. One of the examples by which he supports his view is the parallel behaviour of the ground-ivy (Nepeta Glechoma) and the box-tree, whose flowers appear simultaneously on 3rd April, as an average date; while in a certain backward year they flowered later, but still close together—namely, 20th April and 19th April. There is to me an especial charm in these duets. Thus I like to imagine that the larch is waiting to put on its new green clothes till it hears the black-cap. Or is it that the larch rules the orchestra, and with his green baton signals to the songster to strike into the symphony? {11}

Shakespeare is right to make the daffodil come before the swallow dares, since according to Blomefield the average of seventeen annual observations gives 12th March for the daffodil’s flowering-day, and the swallow does not appear till 9th April at the earliest. Browning, too, is scientifically safe in letting his chaffinch sing now "that the lowest boughs and the brushwood sheaf round the elm-tree bole are in tiny leaf." Indeed, the most dilatory chaffinch must have been singing since 19th February, and in fortunate seasons might have been heard on 7th January. A floral calendar may be useful as an interpreter in antiquarian problems. Thus Blomefield {12a} says that "the flos-cuculi, or cuckoo-flower of the older botanists, was so called from its opening its flowers about the time of the cuckoo’s commencing his call." The botanist referred to may have been Gerarde, and the flower seems to be Cardamine pratensis, known as lady’s smock, also as the cuckoo-flower. Now the cuckoo begins his song (as the average of Blomefield’s seventeen years’ observation near Cambridge) on 29th April, {12b} and lady’s smock blossoms 19th April. {12c} The coincidence is but moderate, but it is cheering to find in Gilbert White’s Calendar, with its earlier South Country dates, that the events occur together: lady’s smock, 6th to 20th April; cuckoo, 7th to 26th April.

Wood-sorrel (Oxalis acetosella) was known as cuckoo-sorrel by the Saxons. In Stillingfleet’s Calendar of Flora (1755), it is said to flower on 16th April, and the cuckoo to begin his song on 17th April. It is pleasant to find, in a Swedish calendar of flora, that the cuckoo sings on 12th May, and the wood-sorrel flowers on 13th May. Lychnis flos-cuculi, the ragged robin, flowers on 19th May, and seems to have no kind of right to the name of a cuckoo-flower, though Gerarde remarks that it "flowers in April and May, when the cuckoo doth begin to sing her pleasant notes without stammering." {12d}

I remember being told by a physician that a celebrated Polish violinist in his old age could not bear the sound of concerted music, but he would weep over a musical score of which he said, "These beggars don’t play out of tune." This is also true of the great symphony of colour which the springtime unfolds. The trees are double-basses, and doubtless some are contra-fagotti, though I confess that I cannot speak positively on this point. Then come a mass of beautiful shrub-like plants which make up the rest of the string-band. As one who loves wind-instruments, I like to think that the flutes, oboes, and clarinets are the flowers of my vernal orchestra, decorating the great mass of stringed instruments with streaks and flames of colour.

In real music, we cannot say why certain sounds make an appropriate opening for a symphony; nor can we understand why the chorus of flowers should (as above pointed out) be led by mezereon (Daphne mezereum), followed by furze, hazel, the daisy, and the snowdrop.

Of course, their dates are not rigorously fixed: the plants just referred to vary in their dates of flowering in the following way:

Mezereon, 11th January to 2nd February;

Furze, 1st January to 4th April;

Hazel, 1st January to 20th February;

Snowdrop, 18th January to 16th February;

the mean dates being: mezereon, 22nd January; furze, 24th January; hazel, 26th January; snowdrop, 30th January. One cause of variation in the date of flowering is temperature, and in the early months of the year this is probably the principal cause. Temperature must in the same way affect the flowering of summer plants, though the result is not so striking as in the springtime. In my article "A Procession of Flowers" (in this volume) I have given the range of the dates of flowering for different months.

The spring is the happiest season for those who love plants, who delight to watch and record the advent of old friends as the great procession of green leaves and beautiful flowers unwinds itself with a glory which no familiarity can tarnish.

I cannot resist giving the names of some of the flowers that make this familiar show that February and March give us. Field-speedwell (Veronica agrestis), butcher’s broom, Pyrus japonica, primrose, red dead-nettle, crocus, dandelion, periwinkle, celandine, marsh-marigold, sweet violet, ivy-leaved veronica, daffodil, white dead-nettle, colt’s-foot (Tussilago farfara), dog’s mercury, buttercup (Ranunculus repens), hyacinth, almond-tree, gooseberry, wood-sorrel, ground-ivy, wall-flower. The order in which they occur is taken from the mean dates of flowering given by Blomefield. To a lover of plants, this commonplace list will, I hope, be what a score is to a musician, and will recall to him some of the charm of the orchestra of living beauty that springtime awakens.

NOTES.

{1} From the Cornhill Magazine, March 1919.

{2} The large-leaved lime is described by Hooker as being a doubtful "denizen."

{3} A Naturalist’s Calendar, by Leonard Blomefield (formerly Jenyns). Cambridge University Press. Edited by Francis Darwin, 1903.

{4a} Calendar, p. 3, note b.

{4b} The Student’s Flora of the British Islands, 3rd ed., 1884, p. 191.

{5} I was led to examine them by a writer in The Times (6th February 1918), who describes the buds as being as blue "as wood-smoke from cottage chimneys."

{6} Ludwig has seen creatures, which run on the surface of the water, carry away duckweed pollen. These fertilisers belong to the families Hydrometridæ, Corisidæ, and Naucoridæ.

{7} This, and part of what follows, is from unpublished notes of lectures given at Cambridge.

{11} The present discussion is partly taken from my introduction to Blomefield’s Naturalist’s Calendar, 1903.

{12a} Observations in Natural History, p. 334.

{12b} Earliest date noted, 21st April; latest, 8th May.

{12c} Earliest date, 21st March; latest, 7th May (fifteen years’ observation).

{12d} Quoted in Prior’s Popular Names of British Plants, 3rd ed., 1879, p. 59.

[The end]
Francis Darwin's essay: Springtime

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